Baron Weather XDD-1000C C-BAND DOPPLER WEATHER RADAR User Manual 4017 B FinalRevA
Baron Services Inc C-BAND DOPPLER WEATHER RADAR 4017 B FinalRevA
Contents
- 1. Modulator Manual
- 2. Users Manual Part 1
- 3. Users Manual Part 2
- 4. Users Manual Part 3
- 5. S10 OPERATION AND MAINTENANCE MANUAL
- 6. S10 FAST TRAC MILLENIUM USERS GUIDE
- 7. S10 TECHNICAL MANUAL
- 8. S10 RECEIVER AND PROCESSOR USERS MANUAL PART 1
- 9. S10 RECEIVER AND PROCESSOR USERS MANUAL PART 2
- 10. S10 RECEIVER AND PROCESSOR USERS MANUAL PART 3
S10 OPERATION AND MAINTENANCE MANUAL

OPERATION AND MAINTENANCE 
MANUAL 
ELEVATION OVER AZIMUTH 
POSITIONER 
AL-4017-1EBS-B 
For Baron Services Radars: 
XDD-350C ® 
VHDD-350C ™ 
HDD-350C ™ 
HDD-250C ™ 
VHDD-1000C ™ 
BARON RADAR SERVICES, L.L.C. 
4930 Research Drive 
Huntsville, AL 35805 
PHONE: 256.881.8811     FAX:  256.881.8283 
S10

 1-2
Table of Revisions 
REV DATE DESCRIPTION BY 
A 10/9/03 Added VHDD-1000C to front cover CK 
 i
TABLE OF CONTENTS 
SECTION 1 DESCRIPTIONS........................................................................................................... 1 
1.1 General Description...................................................................................................................... 1 
1.2 Technical Description................................................................................................................... 1 
1.3 Specifications ................................................................................................................................ 1 
1.4 Mechanical Sub-Assemblies......................................................................................................... 1 
1.4.1 Elevation Unit..........................................................................................................................1 
1.4.2 Azimuth Unit...........................................................................................................................2 
1.5 Electromechanical Sub-Assemblies.............................................................................................. 2 
1.5.1 Limit Switches.........................................................................................................................2 
SECTION 2 INSTALLATION & OPERATION................................................................................ 4 
2.1 General.......................................................................................................................................... 4 
2.2 Positioner Installation................................................................................................................... 4 
2.3 Antenna Installation..................................................................................................................... 4 
2.4 Operation Instructions ................................................................................................................. 5 
SECTION 3 MAINTENANCE ........................................................................................................... 7 
3.1 General.......................................................................................................................................... 7 
3.2 Cleaning ........................................................................................................................................ 7 
3.2.1 Exterior Cleaning.....................................................................................................................7 
3.2.2 Interior Cleaning......................................................................................................................8 
3.3 Lubrication ................................................................................................................................... 8 
3.3.1 Periodicity ...............................................................................................................................8 
3.3.2 2000 Hour or 2-Month Lubrication..........................................................................................8 
3.3.3 17000 Hour or 2-year Lubrication............................................................................................8 
3.3 Electromechanical Components................................................................................................. 11 
3.3.2 General..................................................................................................................................11 
3.3.3 Limit Switches Maintenance..................................................................................................11 
3.3.4 Limit Switch Adjustment Procedure (see Figure 1) ................................................................11 
 ii
3.4 Timing Belt Installation And Adjustment ................................................................................. 13 
3.4.1 Belt Tension  (refer to Figure 2) .............................................................................................13 
3.4.2 Sprocket Alignment ...............................................................................................................15 
3.4.3 Belt Handling.........................................................................................................................15 
3.4.4 Belt Storage ...........................................................................................................................15 
3.5 Replacement of Azimuth Motor Assembly ................................................................................ 15 
3.5.1 Removal of Azimuth Motor Assembly...................................................................................15 
3.5.2 Installation of Azimuth Motor Assembly ...............................................................................17 
SECTION 4 STORAGE AND PREPARATION FOR USE.......................................................... 19 
SECTION 5 REPLACEMENT PARTS .......................................................................................... 20 
5.1 PARTS LIST............................................................................................................................... 20 
5.1.1 GENERAL............................................................................................................................20 
5.1.2 ITEM NUMBER (ITEM No.)................................................................................................20 
5.1.3 DESCRIPTION .....................................................................................................................20 
5.1.4 PART NUMBER (PART No.) ...............................................................................................20 
5.1.5 QUANTITY (QTY)...............................................................................................................20 
5.1.6 ORDERING INFORMATION FOR PARTS.........................................................................21 
APPENDIX............................................................................................................................................. 22 
LIST OF TABLE AND FIGURES 
TABLE 1. AL-4017-1EBS-B SPECIFICATIONS.................................................................................. 3 
TABLE 2.  RECOMMENDED LUBRICANTS AND LUBRICATION INTERVALS....................... 10 
FIGURE 1.  LIMIT SWITCH ASSEMBLY......................................................................................... 12 
FIGURE 2: RECOMMENDED BELT TENTION............................................................................... 14 
FIGURE 3.  AL-4017-1EBS-B  POSITIONER ASSEMBLY............................................................... 18 
TABLE 3. AL-4017-1EBS-B Parts List................................................................................................. 21 
 1
SECTION 1 DESCRIPTIONS 
1.1 General Description 
The Positioner AL-4017-1EBS-B is comprised of two modified ORBIT 
Standard AL-760's.   
 The modifications were performed according to Baron Service’s 
specifications concerning speed, acceleration, antenna adapter and 
environmental conditions (see Table 1).                             
1.2 Technical Description  
 The AL-4017-1EBS-B Elevation-over-Azimuth Positioner has two main 
units: Elevation and Azimuth. All parts are submitted to high-stress tests 
to ensure reliability and avoid downtime.  
1.3 Specifications  
 The specifications of the AL-4017-1EBS-B EL/AZ Positioner are listed in 
Table 1.  
1.4 Mechanical Sub-Assemblies  
1.4.1 Elevation Unit  
 The Elevation Unit, mounted on the turntable of the Azimuth Unit, turns 
the upper turntable through the vertical plane. The mechanism of the 
Elevation Unit is as follows: A DC motor drives a worm gear through a 
timing belt. The worm gear drives an internal gear, an integral part of a 
ball race type slewing bearing assembly, which is designed and produced 
according to very high standards and specifications. The internal gear is 
the linking element between the Azimuth and Elevation Units.   

 2
1.4.2 Azimuth Unit  
 The Azimuth Unit turns the Positioner through the horizontal plane. It is 
designed to handle vertical and radial loads. The mechanism of the 
Azimuth Unit is as follows: A DC motor drives a reduction worm gear 
through a timing belt. The pinion on the reduction gear drives an internal 
gear, which is an integral part of a slewing bearing assembly. The internal 
gear drives the turntable, which carries the Elevation unit.  
1.5 Electromechanical Sub-Assemblies  
1.5.1 Limit Switches  
The limit switches are designed to coordinate the rotation of the El axis. 
The limit switches are of the electric rotary cam type. Each limit switch 
assembly has two cams, one for UP and one for DOWN. The limit 
switches are normally open. 

 3
TABLE 1. AL-4017-1EBS-B SPECIFICATIONS 
PARAMETERS                                                                     UNIT                VALUE 
AZIMUTH BEARING MOMENT  
CAPACITY                  ft-lbs   3000  
VERTICAL LOAD                                    lbs      800   
DELIVERED TORQUE            Azimuth      ft-lbs   170                                 
 Elevation     ft-lbs   170      
WITHSTAND TORQUE            Azimuth       ft-lbs   500                                 
 Elevation     ft-lbs   500      
NOMINAL SPEED               Azimuth     deg/sec.     36      
 Elevation     deg/sec.      36      
DATA TAKE-OFF ACCURACY      Azimuth          deg.     ±0.07
 Elevation       deg. ±0.07     
MAXIMUM BACKLASH            Azimuth          deg.     0.05   
 Elevation        deg.     0.05   
ELEVATION LIMIT-TO-LIMIT TRAVEL          deg.     -2 to +182 
AZIMUTH TRAVEL                  deg Continuous 
OPERATING TEMPERATURE                          °C       -20 to +55   
WEIGHT                                          lbs      950      
Note:  
When slip rings and/or rotary joints are used, limit switches are disabled. 

 4
SECTION 2 INSTALLATION & OPERATION 
2.1 General 
 The AL-4017-1EBS-B Elevation over Azimuth positioner is shipped as a 
ready-mounted unit (pedestal assembled on base riser).   
Unpack the system and examine it for any damage that may have 
occurred in transit. Check connectors, units, the base, and the body itself. 
The site on which the Positioner is to be placed must be adequate to 
support its weight. Unless otherwise stated, Positioners are dispatched 
with the upper turntable in the zero position and locked on zero.   
2.2 Positioner Installation  
 Using an adequate hoisting device and lifting eye, place the Positioner on 
the designed location and clamp it with 3/4" UNC bolts and torque to ≈100 
ft-lbs.  
2.3 Antenna Installation  
 CAUTION 
To prevent injury to personnel and damage to equipment, always 
make sure that the SAFE/OPERATE switch on the connector panel is 
set to SAFE, prior to antenna installation on Positioner.  
 a.     The antenna should be fastened to the upper turntable using the 
specially designed antenna support. When mounting the antenna it is 
important to consider the Positioner's bending moment rating. The 
weight of an antenna assembly, wind, and/or ice-formation may all 
subject a Positioner, located in the open, to a bending moment. 
When approaching the Positioner's maximum rating, caution should 

 5
be exercised since the additional moment load on the antenna from 
wind force may be enough to exceed the maximum load rating.  
 b.      Inertia loading must also be considered since, during both 
acceleration and deceleration, the torque load on the drive train 
mechanism increases. Inertia overload causes slow starting and 
commensurate increase in motor current to compensate for the 
excessive drive torque required. Faltering, vibration, and exceeding 
of the torque rating on deceleration may all result from inertia 
overload, causing excessive gear wear and possible tooth breakage.  
 CAUTION  
To avoid damage to the Positioner drive train from inertial overload, 
it is vital to apply speed changes slowly whenever an overload is 
suspected. This is because inertial torque effects are proportional 
to the square of the turntable speed.   
2.4 Operation Instructions  
 CAUTION 
Prior to any operation of the Positioner, make sure that no person 
or equipment is inside the Positioner rotation area. 
a. Set the "SAFE/OPERATE" switch to "OPERATE" position. 
b. Set Power Switch on the Controller to the "ON" position - "ON" lamp 
will illuminate. The positioner will perform a self-test by slewing in 
both azimuth and elevation.  
c. Upon completion of the self-test, choose between "LOCAL" operation 
(operation by means of the Controller) or "REMOTE" operation 
(operation by means of the Computer) by setting the Controller to the 
desired mode of operation, using the LOCAL/REMOTE switch. The 
Positioner and System are now ready to operate. 

 6
d. To operate the System, refer to the applicable Controller Operation 
Manual.   
 WARNING 
TO PREVENT INJURY TO MAINTENANCE PERSONNEL 
OR DAMAGE TO EQUIPMENT, ALWAYS VERIFY THAT 
NO EXTERNAL VOLTAGE IS SUPPLIED TO THE 
POSITIONER AND THAT THE SAFE/OPERATE SWITCH 
IS IN THE SAFE POSITION, PRIOR TO PERFORMING 
ANY MAINTENANCE WORK ON THE POSITIONER. 
IF POWER MUST BE APPLIED FOR TEST PURPOSES, 
TAKE ALL THE STEPS THAT ARE NECESSARY IN 
ORDER TO AVOID INJURIES AS A RESULT OF 
ELECTRICAL SHOCKS AND MOVEMENT OF 
MECHANICAL UNITS. 

 7
SECTION 3 MAINTENANCE  
3.1 General  
 This chapter provides information necessary for maintaining the AL-4017-
1EBS-B Elevation-over-Azimuth Positioner series in optimal operating 
condition.  
 Note 
When performing maintenance operations, the internal components 
such as motors, electrical devices, wires, connectors, and 
mechanical elements, should be visually inspected.  
3.2 Cleaning  
 The Positioner should be cleaned as often as dictated by the operating 
conditions. It should be kept free of dust, moisture and grease. If available, 
use a vacuum cleaner to remove all accumulated dust from the interior 
and exterior of the Positioner.  
3.2.1 Exterior Cleaning  
 Loose dust can accumulate on the exterior surface of the positioner. 
Remove this dust with a soft cloth or a soft bristle brush. A cloth saturated 
with cleaning solvent may also be used.  
 8
3.2.2 Interior Cleaning  
 Loose dust in the Positioner interior must be removed due to its electrical 
conductivity under humid conditions. The recommended method is to use 
a vacuum cleaner. Remove any remaining dirt with a soft bristle brush or a 
cloth soaked in cleaning solvent. A cotton-tipped applicator is useful for 
cleaning narrow spaces.  
3.3 Lubrication  
 This section includes access information, periodicity, and lubrication 
procedures.   
3.3.1 Periodicity  
Lubrication of the Positioner should be performed periodically, per the 
intervals listed in Table 2. 
3.3.2 2,000 Hour or 2-Month Lubrication  
3.3.2.1 Slewing Bearing Lubrication  
 a. Inject 2cc of grease (see Table 2), through the grease fitting, 
every 60° of the Azimuth turntable rotation. For Elevation, inject 
grease at the end of the travel, in each direction.   
b. When operating under very hot or dry environmental conditions, 
inspect and inject grease more frequently.   
3.3.3 17,000 Hour or 2-year Lubrication 
3.3.3.1 Ring-Gear Lubrication  
 a. Using a 5/32-inch Allen wrench, loosen the two screws fastening 
the primary limit switch assembly to the body.  

 9
 b. Through the limit switch hole in the body apply a thin layer of 
grease on the gear teeth. Then, rotate the turntable a small 
amount and again apply a thin layer of grease on the gear teeth. 
Continue this rotating and greasing process until the turntable 
completes one full revolution.    
 c. Remount the limit switch after rotating the turntable to its previous 
position.  
 Note 
To achieve the previous position, verify that the angle that is 
displayed on the controller's console is the same angle that was 
displayed before the removing of the limit switch assembly.   

 10
TABLE 2.  RECOMMENDED LUBRICANTS AND LUBRICATION INTERVALS 
Item    Lubricant Type      Manufacturer    Interval    
Large ring Grease    Molykote      Dow Corning   17,000 hours of  
gear       165 LT        GmbH             operation or  
        2 years  
Bearings   Grease    Isoflex       Kluber        1,500 hours of  
    LDS 18           operation or  
    Special A        2 months     
Reduction  Grease    Shell Tivella Shell Oil Co. During        
gear          Compound A       overhaul      
Note:    If the required Lubricants, as described in the above table, are not 
available in your area; please contact your Baron Services 
Representative for assistance. 

 11
3.3 Electromechanical Components  
3.3.2 General  
 Common components, such as encoders and limit switches, do not 
usually require special servicing; such components may be serviced 
during general overhaul. Maintenance information for the limit 
switches is given in the following pages.   
3.3.3 Limit Switches Maintenance  
 The limit switches are factory adjusted prior to shipment. However, 
when Positioner readjustment or change of rotation limits is 
necessary, the limit switches must be readjusted.  
 CAUTION 
To avoid damage to the internal cables  (connecting the Azimuth 
Unit to the Elevation Unit), verify that the new adjusted turning 
range does not exceed the specified range.   
3.3.4 Limit Switch Adjustment Procedure (see Figure 1) 
 a.  Turn Positioner axis to the desired limit angle (CW or CCW).  
b.  Gain access to limit switch assembly.  
c.  Using a 7/64" Allen wrench, release the appropriate limit 
switch cam fastening screw  (S1 for CCW and S2 for CW).  
d.  Rotate the appropriate switch cam until Positioner operation is 
inhibited in the desired direction and retighten the cam screw.  
e.  Turn the Positioner in the opposite direction and then return it 
in the limit direction. Verify that Positioner operation is stopped 
at the desired angle.  

 12
FIGURE 1.  LIMIT SWITCH ASSEMBLY 
 13
3.4 Timing Belt Installation And Adjustment  
 The Timing belt should be installed with a snug fit, neither too tight nor too 
loose. The belt's positive grip eliminates the need for initial tension. 
Consequently, a belt, when installed with a snug fit  (that is, not too tight), 
assures longer life, less wear on bearings and quieter operation. 
Preloading, often the cause of premature failure, is not necessary. 
3.4.1 Belt Tension  (refer to Figure 2) 
 When torque is unusually high, a loose belt, on starting, may "jump teeth". 
In such a case, the tension should be increased gradually until satisfactory 
operation is attained.  
When the safety switch is in the OPERATE position, run the polarizer so 
that the top of the belt is slack and return the safety switch to the SAFE 
position. The application of a force (f) of 1.3 lbs (0.59 Kg) at the midpoint 
of the slack span, between the two pulleys, shall result in a deflection (d) 
of 0.21 inch (5.4mm).  
If the force (f) required to obtain the specified deflection (d) is less than 
specified, the belt is too loose. If the force (f) required to obtain the 
specified deflection (d) is greater than that specified, the belt is too tight. 
Adjust the motor position until the specified force and deflection 
measurements are obtained.  

 14
FIGURE 2: RECOMMENDED BELT TENTION
d = 0.21 inch  (5
.4 mm)
f = 1.3 lbs       (0.59 Kg.) 
 15
3.4.2 Sprocket Alignment  
 Misalignment of drive results in unequal tension and extreme edge wear. 
Consequently, sprocket alignment should be verified by means of a 
straight-edge and shafts checked to assure parallelism. On a long-center 
drive, due to the belt's tendency to run against one flange of the drive 
sprocket, it is often advisable to offset the driven sprocket slightly to 
compensate for this effect.  
3.4.3 Belt Handling  
 On installation, the belt should never be forced or pried over the sprocket 
flange. Reduction of center distance usually permits the belt to slide into 
the sprocket easily. Otherwise, one or both sprockets must be removed.  
3.4.4 Belt Storage 
 To assure smooth operation and to prevent premature failure, belts in 
storage should be protected against sharp bending or creasing. Avoid 
subjecting belts to extreme heat, low temperature or high humidity. 
3.5 Replacement of Azimuth Motor Assembly 
3.5.1 Removal of Azimuth Motor Assembly 
 Use the following procedure to remove the Azimuth Motor Assembly 
(Refer to Figure 3): 
a. Rotate the Elevation Axis until it is at the 90 deg. vertical position; 
i.e. pointing straight up.   

 16
b. Set the SAFE/OPERATE switch to the SAFE position. 
c. Remove the antenna, counterweights, and the two arms located on 
the Elevation Axis. 
d. Remove the four screws on each flange (8) and the screws (3) 
securing the Positioner to the base riser. 
e. Detach the connectors MOL1 thru MOL4, located in the base riser. 
f. Lift the Positioner off of the base riser and place it on a secure 
working surface; e.g. a table. 
g. Support the Positioner in a level position. 
h. Remove screws (6), cut the tie wraps located on the waveguide and 
remove the parts (7) from the Slip-Ring. 
i. Remove the screws (4) securing the lower plate (5) to the Azimuth 
unit. 
j. Separate the lower plate (5) from the Azimuth unit. 
 Note: 
   The length of the wiring harness between the slip-ring and the 
elevation unit is long enough to allow the plate (5) to be moved 
away from the Azimuth unit by a distance of approximately one foot. 
k. Remove the four screws securing the motor bracket to the azimuth 
positioner body. 
l. Using a "heat gun", remove the LOCKTITE No. 241 epoxy from the 
four screws securing the motor to the bracket. 
m. Remove the four screws attaching the motor to the bracket. 
n. Carefully, remove the motor from the bracket. 

 17
o. Remove the pulley from the motor shaft and retain it for installation 
on the shaft of the new motor. 
3.5.2 Installation of Azimuth Motor Assembly 
 For new Azimuth Motor installation, follow the removal procedure in 
paragraph 3.6.1 in a logical reverse sequence using the following notes: 
 Notes: 
1) When the lower plate (5) is assembled to the Azimuth unit, be sure 
that the extra length of the wire harness between the slip-ring and 
the elevation unit is inserted in part (1). Loose wiring inside the 
Azimuth unit should be secured to the waveguide by means of tie 
wraps. 
2) When assembling the positioner, verify that the waveguide and 
lower plate (5) O-ring gaskets are in good condition and are 
installed in their proper locations. Verify that all screws are securely 
fastened. 
3) After the installation procedure is completed, the new motor and gear 
sprockets must be aligned according to para. 3.5.2; and the tension of 
the belt between the new motor and the gear must be adjusted according 
to para. 3.5.1.   

 18
FIGURE 3.  AL-4017-1EBS-B  POSITIONER ASSEMBLY
 19
SECTION 4 STORAGE AND PREPARATION FOR USE  
Store the Positioner in a closed place, protected from dust and rain.  
Once a month, rotate the Positioner at each axis, three times from limit to limit. 
Before using the Positioner after a long storage period, re-lubricate the bearings. 
Refer to lubrication instructions. 
 20
SECTION 5 REPLACEMENT PARTS 
5.1 PARTS LIST 
5.1.1 GENERAL 
 The various parts used in the AL-4017-1EBS Positioner are listed in the 
following parts list table. The purpose of this part list is for identification, 
requisition, and issuance of spare or replacement parts. For part replacement, 
use only part numbers specified in this parts list. 
 The parts list table is divided into four columns, which are described in the 
following paragraphs. 
5.1.2 ITEM NUMBER (ITEM No.) 
 The first column in the parts list table contains item numbers, assigned in 
sequence. 
5.1.3 DESCRIPTION 
 The second column contains brief descriptive information for each part. 
5.1.4 PART NUMBER (PART No.) 
 The third column lists manufacturer's part numbers. 
5.1.5 QUANTITY (QTY) 
 The fifth column lists quantity of each item used in the Positioner. 

 21
5.1.6 ORDERING INFORMATION FOR PARTS 
 When ordering spare or replacement parts, state the full description of part, part 
number, and the desired quantity. 
TABLE 3. AL-4017-1EBS-B Parts List 
Item 
No. 
Description Part No. Qty. 
1. Az. Motor Assy. BS-104453 1 
2. El. Motor Assy. BS-104452 1 
3. Encoder BS-104455 2 
4. Reduction Gear BS-104151 2 
5. Pulley (Az/El) (Motor) BS-104482 2 
6. Belt BS-104456 2 
7. Pulley (Az/El) (Gear) BS-104483 2 
8. Slewing Bearing BS-104107 2 
9. Az Power Amp. BS-104134 1 
 22
APPENDIX  
AL-4017-1EBS-B 
INTERFACE CONTROL DRAWING (ICD) - Dwg. No. 19-0342 
WIRING DIAGRAM     - Dwg. No. 19-0361-1/2 
SYSTEM LAYOUT     - Dwg. No. 19-0589 

OPERATION AND MAINTENANCE 
MANUAL 
AL-1642-3JB 
Two-Axis Controller 
With Built-In Servo Amplifier 
For Baron Services Radars: 
XDD-350C ™ 
XDD-300X ® 
VHDD-350C ™ 
VHDD-1000C™ 
BARON SERVICES, INC. 
4930 Research Drive 
Huntsville, AL 35805 
PHONE: 256.881.8811     FAX:  256.881.8283 

Table of Revisions 
REV DATE DESCRIPTION BY 
A 10/9/03 Added VHDD-1000C to front cover CK 
TABLE OF CONTENTS 
SECTION 1 INTRODUCTION .................................................................................... 1 
SECTION 2 FRONT PANEL OPERATION............................................................... 2 
2.1 Front Panel Keypad................................................................................................ 2 
2.2 Front Panel Joystick and Fine/Coarse Switch ....................................................... 3 
2.3 Front Panel Power Switch...................................................................................... 3 
2.4 Front Panel Display ................................................................................................ 4 
SECTION 3 REAR PANEL CONFIGURATION ....................................................... 5 
3.1 Power Selection, Input, and Fuses.......................................................................... 5 
3.2 Motor Fuses............................................................................................................. 5 
3.3 Positioner Connectors ............................................................................................. 6 
3.3.1 Encoder IN/OUT (J3).............................................................................................6 
3.3.2 Motor Power and Limits (J5)..................................................................................6 
3.4 Communication Connectors ................................................................................... 7 
SECTION 4 REMOTE OPERATION.......................................................................... 8 
4.1 Modes of Operation ................................................................................................ 8 
4.1.1 Standby..................................................................................................................8 
4.1.2 Point ......................................................................................................................9 
4.1.2.1 Single Point Commands .........................................................................................9 
4.1.2.2 Repeated Point Commands (Track Mode)..............................................................9 
4.1.3 Home ...................................................................................................................10 
4.1.4 Slew.....................................................................................................................10 
4.1.5 Calibrate ..............................................................................................................10 
4.1.6 Raster Scan Mode ................................................................................................11 
4.1.6.1 Azimuth Raster Scan Mode ..................................................................................12 
4.1.6.2 Elevation Raster Scan Mode.................................................................................13 
4.2 Serial Protocol - Data Link Level......................................................................... 14 
4.3 Serial Protocol - Commands from Host Computer to ACU................................ 15 
4.4 Serial Protocol - Replies from ACU to Host......................................................... 16 
4.5 Command codes and parameters ......................................................................... 18 
4.5.1 General comments................................................................................................18 
4.5.2 Parameter Limits..................................................................................................18 
4.5.3 Alphabetical command listing..............................................................................19 
SECTION 5 TROUBLESHOOTING......................................................................... 28 
SECTION 6 MAINTENANCE.................................................................................... 30 
6.1 Amplifier Adjustment........................................................................................... 30 
6.2 Voltage Tests ......................................................................................................... 30 
APPENDIX A................................................................................................................... 31 
APPENDIX  B .................................................................................................................. 42 
1 INTRODUCTION 
 The AL-1642-3JB is a higher power version of the AL-1613-3JB 
Antenna Control Unit (ACU) for controlling a two-axis elevation-
over-azimuth positioner.  A front panel provides manual control of 
the antenna from the controller through a joystick, a set of 
pushbuttons, and two 8-character LED displays, one for each axis. 
Two RS-232 serial links are provided.  One link provides for 
remote control and parameter tuning. Modes of operation in remote 
control include Go-to-Point, Slew, Raster Scan, Go-to-Home 
Position, Standby, and Calibrate.  The second link provides 
azimuth and elevation position continuously. 
Go-to-Point mode includes an extrapolation algorithm designed to 
allow the controller to closely follow a trajectory sent over the 
serial link.  This algorithm is used automatically when point 
commands are received at a sufficiently rapid rate.  Most important 
control gains and parameters may be tuned over the serial link and 
stored in non-volatile memory. 
The AL-1642-3JB is packaged in a 4U height 19"-wide rack-
mount box which includes DC  power supplies, a CPU card, an I/O 
card, two amplifiers for the DC motors, and the front panel card. 
The CPU card, based on the Intel 80960KB RISC processor, 
performs closed loop control of the axis positions and manages the 
serial protocol and front panel.  The I/O card contains inputs for 
encoders to read axis positions, digital inputs for limit switches, 
digital outputs for the drive enable and analog outputs for the 
current references for the motors.  It also contains the serial 
communications chip and drivers for the RS-232 communication 
link.  The front panel card provides interfaces for the joystick, the 
pushbuttons, and the 8-character displays for reading the angles. 
The amplifiers provide closed loop velocity control of the motors, 
as well as protective functions, such as constant current limiting, 
peak current limiting, clockwise motion limiting, and 
counterclockwise motion limiting. 
2 FRONT PANEL OPERATION 
 The front panel is shown in Figure B-3.  It consists of a joystick, a 
fine/coarse switch, two 8-character displays, two LEDs, three 
pushbuttons, and an on/off power switch. 
When the AL-1642-3JB is first powered on, the unit will be in 
REMOTE mode, permitting remote operation without access to the 
Controller. 
2.1 Front Panel Keypad 
 The front panel contains 3 pushbuttons with functions as follows: 
REM/LOC  - Toggle between remote and local modes.  In remote 
mode, the other front panel controls are inactive and all control is 
by commands over the serial communications link.  In local mode, 
commands over the serial link which could move the positioner are 
not accepted.  This includes axis mode commands and pointing 
commands. Position is controlled instead through the joystick and 
other front panel switches. The REM/LOC switch also places the 
controller in Standby mode whenever it is pressed, bringing the 
positioner to zero velocity.  
CAL  - This function is required because the position measurement 
is based on incremental encoders. It finds the mechanical zero 
point of the positioner and resets the angle displays accordingly. 
A detailed explanation of the calibration sequence and the 
parameters that affect it is given in section 4.1.5 below. 
OFFSET  - Set azimuth offset so that the present angle will be zero. 
If the positioner is moving, it is first commanded to zero velocity.  
If the positioner is calibrated, the offset is saved to non-volatile 
memory. 
2.2 Front Panel Joystick and Fine/Coarse Switch 
 The joystick is a dual axis unit with a spring return to zero. It allows 
controlled movement of both axes at a wide range of velocities when in 
MANUAL mode. Movement of the joystick UP or DOWN causes elevation 
motion in the CW or CCW direction respectively. Movement to the right or 
left causes CW or CCW azimuth motion. 
The joystick is a very sensitive control unit. An excessive amount of force is 
not required in order to move the stick. Extreme force can cause damage to 
the joystick. 
The velocity varies with the amount the joystick is moved from its center 
position. A central region of approximately ±10% of the joystick's total travel 
range gives zero velocity. The next ±40% gives a velocity range which 
increases slowly at first and then increases rapidly. The last ±50% of the travel 
provides a velocity which increases at a linear rate with respect to joystick 
position. In all ranges, a deadband of ±2.5% keeps the velocity constant until a 
motion of at least 2.5% of the stroke length is made. 
A front panel velocity parameter, which may also be adjusted via the 
communications link, is the maximum velocity when the FINE/COARSE 
switch is set to COARSE. With the FINE/COARSE switch set to FINE, the 
maximum velocity is reduced by a factor of 10. 
With a typical maximum velocity of 36 deg/sec., velocities of about 0.3 
deg/sec. to 36 deg/sec. are possible in COARSE mode, and 0.03 deg/sec. to 
3.6 deg/sec. in FINE mode. 
Zero-adjust levers are provided for each axis of the joystick. If a small 
velocity exists, with the joystick at the center position, this may be nulled by 
adjusting these levers. 
2.3 Front Panel Power Switch 
 This switch will switch the main power, which may be either 115 VAC or 230 
VAC, depending on settings of rear panel switches described below. The 
switch will be illuminated when 230 VAC power is in use and the switch is in 
the ON position. 
2.4 Front Panel Display 
 Azimuth and Elevation angles are displayed on the front panel using 8-
character LED displays.  Six of the characters provide the angle reading to a 
precision of 0.001 degree.  The 7th character is for the sign of the angle, and 
the 8th character provides limit information. 
A rapidly blinking display (4-Hz) indicates that the axis has not completed its 
calibration cycle.   
A slowly blinking display (2-Hz), along with a letter in the limit character, 
indicates that a limit switch has been tripped, stopping the positioner motion.  
Motion is then permitted only in the direction away from the limit.   
 L (left) indicates CCW azimuth limit (decreasing angle).   
 R (right) indicates CW azimuth limit (increasing angle).   
U (up) indicates CW elevation limit, and D (down) indicates CCW 
 elevation limit. 
A slowly blinking letter in the limit character, with the rest of the display not 
blinking, indicates that the positioner has reached the software limit maximum 
or minimum angle.  These limit angles may be adjusted by commands over 
the serial communication link. 
The angle display may be changed by commands CCA and CCE on the serial 
communications link.  The precision may be set to 0.1, 0.01, or 0.001 degree.  
The format may be set to 0-359.999 or +/-780 degrees.  If desired, the limit 
character may be displayed (without blinking) to indicate cable wrap (when 
the angle is outside the center +/-180 degree area).  This cable wrap feature is 
particularly useful with a 0-359.999 degree display format. 
3 REAR PANEL CONFIGURATION   
 The rear panel is shown in Figure B-4.  It contains a power select area, power 
input, fuses, a connector for the cable to the positioner, two communications 
connectors, and a chassis ground connector. 
3.1 Power Selection, Input, and Fuses 
 Power input is through the power connector J1. 
The switch labeled "MAINS SELECT" has two positions, 115 VAC and 230 
VAC. 
 The "MAINS SELECT" switch must be set to the proper 
input voltage.  If this is not done, damage may result to 
the internal power supply used to provide DC current for 
the positioner motors and the electronic circuitry. 
Fuse F1 is for the AC input.  Recommended fuses to be used are 4 Amp 
"slow-blow" type for 230 VAC input, 8 Amp "slow-blow" type for 115 VAC.  
High breaking capacity fuse (greater than 500 Amps) should be used. 
3.2 Motor Fuses 
 Fuse F2 protects the azimuth motor and fuse F3 protects the elevation motor.  
Current limit protection already exists in the amplifiers and is set to 5 Amps 
continuous and 10 Amps for peaks of less than 2 seconds.  This will protect 
the motors from thermal overheating for ambient temperatures up to about 
45°C.  "Slow-blow" type fuses of 10 Amps are recommended as further 
protection. 
3.3 Positioner Connectors 
 The positioner connectors J3 and J5 are circular MS-type connectors which 
carry encoder signals, tachometer signals, limit switch signals, and power for 
the motors and encoders.   
3.3.1 Encoder IN/OUT (J3) 
 For each encoder, there are 6 wires, in three sets of shielded twisted pairs.  
One pair is for the normal (A) pulses, one pair for the quadrature (B) pulses, 
and one for the index (I) pulses.   
For each axis, there are two wires for a home (zero-indicating) pulse which  is 
used during the calibration operation to find an absolute reference point. 
115/230 VAC  is provided as input to a power supply which provides 5 Vdc 
power to the encoders. 
For each tachometer (azimuth and elevation), there are two wires. 
3.3.2 Motor Power and Limits (J5) 
    Each motor has 6 wires, one group of three connected in parallel for DC 
power-high side and the second group of three connected in parallel for DC 
return. 
For each axis, there are 3 limit switch wires: one for CW limit, one for CCW 
limit and one for common.  The CW and CCW limits will shut down the 
motor amplifiers from moving the motors in the direction which caused the 
limit.  
3.4 Communication Connectors 
 The communication connector J4 is a 25-pin D-type connector for RS-232, 
with pins 2,3, and 7 used for TXD, RXD, and COMMON, respectively per 
standard RS-232 configuration.  The controller is configured as DCE (data 
communications equipment), since normally the host computer will be 
configured as DTE (data terminal equipment).  This means that the controller 
receives data from the host on pin 2 (TXD) of the 25-pin connector and 
transmits data to the host on pin 3 of the 25-pin connector (RXD). 
Connector J6 is a 25-pin D-type connector for RS-232, configured the same as 
J4.  The azimuth and elevation status data are transmitted via connector J6.  
4 REMOTE OPERATION   
 Remote operation is implemented by sending commands to the positioner via 
the serial link. The modes of operation available via remote control and the 
details of the serial protocol commands are described below. 
4.1 Modes of Operation 
 The mode of operation for each axis is independent.  The modes of operation 
are: MANUAL, STANDBY, POINT, HOME, SLEW, RASTER SCAN, and 
CALIBRATE. A mode command may be used to select all but the first via the 
remote link.  Following is a description of what occurs when each mode is 
selected. 
4.1.1 Standby 
 Axis is brought to a stop at the maximum allowed deceleration rate, 
determined by the parameter MAx.  When the velocity arrives at zero, the 
motor amplifier is shut down if bit #12 in Control Word #2 is set.  This bit 
should be set only for positioners which have self-locking gears, or for which 
there is no load imbalance which would cause the positioner to move when 
the amplifiers are shut down. 
Note that Standby may also be implemented from the Controller front panel 
by toggling the REMOTE/LOCAL switch.  
Note that if Standby is commanded before the power-up calibration has been 
performed, the position readings will be relative to the position at which the 
unit was powered-up. The front-panel display will blink at 4 Hz. repetition 
rate to indicate this, and the status bit in RDS (az_calibrated or el_calibrated) 
will be 0. 
4.1.2 Point 
4.1.2.1 Single Point Commands 
 Positioner moves to the axis point reference, as sent by the PTx command, 
and comes to rest there.  The amplifier continues to supply current as needed 
to hold the position against external forces. 
 If the positioner has been switched from LOCAL to REMOTE and no point 
command has been sent, the axis point reference is the place where the 
positioner came to rest. 
When a single PTx command is send while the ACU is in Remote and Point 
mode, the positioner moves to the commanded point using a trapezoidal 
velocity profile. 
 If the Continuous Rotation bit (bit #5) in Control Word #1 is set, the direction 
of motion is the shortest route, and the user has no control over the direction. 
If it is not set, the direction of motion is according to the commanded values.  
For example, if the position is +170.000 and the user wishes to move 20 
degrees CW, the commanded point  must be +190.000.  If he wishes to reach 
the same point by a 340 degree motion CCW, the commanded point must be -
170.000. 
The acceleration is determined by the value of the MAx parameter. 
The maximum speed is determined by the step size, the MVx parameter, and 
the "Full-Speed Step" bit (bit #6) in Control Word #2.  If "Full-Speed Step" is 
set, the maximum speed will be the MVx parameter for all step sizes greater 
than MVx2/MAx.  For smaller steps, the velocity profile will be triangular.  If 
"Full-Speed Step" is zero, the maximum velocity will be according to the 
formula sqrt(step*MAx/5.0), or MVx, whichever is less.  For applications 
where there are many small, irregular position corrections being commanded, 
and response time is not critical, this formula provides smoother motion with 
good response time. 
4.1.2.2 Repeated Point Commands (Track Mode) 
 If a series of point commands are sent when in point mode, and the time delay 
between commands is less than the maximum update-time (UTx) parameter, 
the points will be interpreted as a continuous trajectory.  Instead of coming to 
rest, the positioner extrapolates the trajectory based on the last two points 
received and attempts to arrive at the point and velocity expected according to 
the extrapolated trajectory. This  mode is entered after 3 points have been sent 
with the two time intervals between them less than the maximum update-time. 
As long as the update time varies by less than 10%, the trajectory 
extrapolation is based on the assumption that the intended time interval was 
constant.  If the time interval between points is more than this, the positioner 
begins to decelerate to zero velocity.  
4.1.3 Home 
 Positioner moves to the home point (HMx) parameter specified for the axis 
and comes to rest there.  The amplifier continues to supply current to hold the 
positioner at that point against external forces. 
Home mode acts like a single point command, but using the HMx parameter 
to determine the target point instead of the PTx parameter. 
4.1.4 Slew 
 Positioner moves at the constant velocity last commanded with a slew velocity 
(SVx) command.  If no slew velocity command has been sent since the 
controller was turned on, the slew velocity is zero. 
4.1.5 Calibrate 
 This function is required because the position measurement is based on 
incremental encoders. It finds the mechanical zero point of the positioner and 
resets the angle displays accordingly.  First, the positioner moves towards the 
clockwise limit switch at the go-to-limit velocity until one of three events 
occurs: 
   1) The clockwise limit switch is tripped 
   2) The zero indicating pulse is detected 
   3) The maximum clockwise calibration distance is 
 passed 
In cases 2 and 3, if required, the positioner moves clockwise an additional 
distance to be sure that it will accelerate to the calibrate velocity before it 
reaches the zero-indicating pulse. 

The positioner then moves counter clockwise at the calibrate velocity until it 
detects the zero-indicating pulse and continues until the first index pulse on 
the encoder is observed. 
 At this point, the current angle is then set equal to the zero switch position 
minus the offset. The positioner then decelerates and returns to this set point. 
Go-to-limit velocity, calibrate velocity, maximum clockwise calibration 
distance, zero switch position, and offset for each axis may all be adjusted via 
the serial communication link. 
 Notes:    
1.If the zero switch position parameter is changed without performing a 
calibration, the current angle readout will not be changed until a calibration is 
actually performed. 
2.Calibration is performed automatically upon power-up. 
3.For a continuous rotation axis, as defined by bit 5 in control word #1, the 
clockwise movement in the calibration cycle is not performed.  Instead, the 
axis is moved counterclockwise until the zero-indicating pulse is detected, 
continues until the first index pulse on the encoder is observed, and sets the 
current angle equal to the zero switch position minus the offset, as described 
above. It then decelerates and returns to this set point. 
4.1.6 Raster Scan Mode 
 Positioner performs a raster scan using a rectangular angular profile.  The 
Raster Scan mode is different from all the other modes in that the mode 
command for one axis (primary axis) also controls the operation of another 
axis (secondary axis).  If the Raster Scan mode command is for the azimuth 
axis (i.e., “MDA 6”), the raster area is covered by scanning the azimuth axis 
(primary axis) followed by stepping of the elevation axis (secondary axis) at 
the end of each azimuth scan.  If the Raster Scan mode command is for the 
elevation axis (i.e., “MDE 6”), the raster area is covered by scanning the 
elevation axis (primary axis) followed by stepping of the azimuth axis 
(secondary axis) at the end of each elevation scan.  When a Raster Scan 
command has been initiated for the primary axis, mode commands for the 
secondary axis should not be given until the primary axis is commanded to 
another mode. 
Seven parameters and four control bits govern the details of the raster scan 
performed: 
 RCA Center azimuth position 
  RCE Center elevation position 
  RRA Azimuth range scanned at constant velocity. The azimuth range 
will have added to it at each end an acceleration distance of 
 0.5*RVA*RVA/MAA. 
  RRE Elevation range scanned 
  RVx Scan speed of primary axis in Raster Scan mode command 
  RSx Step size of secondary axis 
  RTx Time delay at end of each scan 
4.1.6.1 Azimuth Raster Scan Mode 
When the Azimuth Raster Scan mode is entered, the positioner moves to the 
initial corner of the raster profile at the maximum velocity (MVx).  The initial 
corner is determined by the sign of the RVA and RSA parameters.  If RVA is 
positive, the initial corner is the CCW corner in azimuth. If RSA is positive, 
the initial corner is CCW in elevation. 
After the initial corner is reached, the positioner scans in azimuth with 
elevation constant until the end of the azimuth range, and decelerates to zero 
velocity. 
If the RTA parameter is nonzero, it waits for a delay time as specified by the 
RTA parameter.  If the bit for a single-direction raster is set (Control Word #2, 
bit 4), the positioner then steps in elevation an amount given by the RSA 
parameter and returns to the azimuth starting point, both together at maximum 
velocity, and the azimuth scan repeats. 
If the single-direction bit is cleared, the elevation steps and the azimuth scans 
in reverse. 
The process is repeated until the next elevation step results in exceeding the 
range specified in the RRE parameter.  At this point, if the Non-Stop Raster 
bit (Control Word #2, bit 5) is set, the positioner returns to the initial corner 
and the process is repeated. 
If Non-Stop Raster is cleared, the positioner enters Standby mode at the end of 
the scan. 
Note that parameters may be changed in the middle of a scan, but this should 
be done with caution.  The parameter change will normally take effect at the 
end of each azimuth sweep.  Changes of sign in RVA or RSA, or changes to 
RCx or RRx may have the effect of placing the positioner outside the scan 
limits, in which case it will scan until it reaches maximum position (MNx or 
MXx) or a limit switch.  Changes in RVA or RSA without a change in sign 
are OK. 
Two control bits which may affect scanning are the Fast Step bit (Control 
Word #2, bit #6) and the Continuous Rotation bit (Control Word #1, Bit #5). 
If the Fast Step bit is not set, the various step motions at the end of each 
azimuth scan may not proceed at their maximum velocity.  The user may 
choose, according to his preference, for fastest completion of scanning or 
smoother motions between azimuth scans. 
If the Continuous Rotation bit is set for azimuth, all step motions at the end of 
azimuth scanning will be in their shortest possible direction.  Therefore, in 
single direction scanning, the "return" motion will be in the same direction as 
the scan for scans greater than 180 degrees. 
If it is desired to scan in azimuth only; i.e., with no elevation motion, set both 
the elevation step size (RSA) and range (RRE) to zero. 
4.1.6.2 Elevation Raster Scan Mode 
This mode is analogous to the Azimuth Raster Scan mode, with the roles of 
the two axes reversed; ie., the positioner scans in elevation and steps in 
azimuth. 
When the Elevation Raster Scan mode is entered, the positioner 
moves to the initial corner of the raster profile at the maximum velocity 
(MVx).  The initial corner is determined by the sign of the RVE and 
RSE parameters.  If RVE is positive, the initial corner is the CCW 
corner in elevation. If RSE is positive, the initial corner is CCW in 
azimuth. 
After the initial corner is reached, the positioner scans in elevation with 
azimuth constant until the end of the elevation range, and decelerates 
to zero velocity. 
If the RTE parameter is nonzero, it waits for a delay time as specified 
by the RTE parameter. 
If the bit for a single-direction raster is set (Control Word #2, bit 4), the 
positioner then steps in azimuth an amount given by the RSE 
parameter and returns to the elevation starting point, both together at 
maximum velocity, and the elevation scan repeats. 
If the single-direction bit is cleared, the azimuth steps and the elevation 
scans in reverse. 
The process is repeated until the next azimuth step results in 
exceeding the range specified in the RRA parameter.  At this point, if 
the Non-Stop Raster bit (Control Word #2, bit 5) is set, the positioner 
returns to the initial corner and the process is repeated. 
If Non-Stop Raster is cleared, the positioner enters Standby mode at 
the end of the scan. 
Note that parameters may be changed in the middle of a scan, but this should 
be done with caution.  The parameter change will normally take effect at the 
end of each elevation sweep.  Changes of sign in RVE or RSE, or changes to 
RCx or RRx may have the effect of placing the positioner outside the scan 
limits, in which case it will scan until it reaches maximum position (MNx or 
MXx) or a limit switch.  Changes in RVE or RSE without a change in sign are 
OK. 
Two control bits which may affect scanning are the Fast Step bit 
(Control Word #2, bit #6) and the Continuous Rotation bit (Control 
Word #1, Bit #5). 
If the Fast Step bit is not set, the various step motions at the end of 
each elevation scan may not proceed at their maximum velocity.  The 
user may choose, according to his preference, for fastest completion of 
scanning or smoother motions between elevation scans. 
If the Continuous Rotation bit is set for elevation, all step motions at 
the end of elevation scanning will be in their shortest possible direction. 
If it is desired to scan in elevation only; ie., with no azimuth motion, set 
both the azimuth step size (RSE) and range (RRA) to zero. 
4.2 Serial Protocol - Data Link Level 
 Serial communication uses asynchronous protocol with 8-bit word length, 1 
start bit, 1 stop bit, even parity, and a rate of 9600 baud.  Signal levels are RS-
232. 
4.3 Serial Protocol - Commands from Host Computer to 
ACU 
 All commands use printable ASCII characters, plus the ASCII control codes 
as follows: 
  STX (start of text, value 02 hex) 
  ETX (end of text, value 03 hex) 
Each command line sent to the controller consists of an ASCII STX character, 
followed by up to 80 characters of commands, two checksum characters, and 
an ETX character.  The checksum is calculated such that the sum modulo 256 
of all command line bytes (excluding the STX, ETX, and checksum bytes) 
will be equal to the checksum characters interpreted as ASCII-HEX. 
The command line consists of a number of commands, each of which is either 
a read command or a write command. 
A write command consists of a 3-letter command followed by a value.  The 
value consists of a number with an optional leading sign (+ or -), up to 8 
digits, and an optional decimal point.  For each parameter, there is a range of 
legal values.  Certain commands will be received only when the controller is 
in the remote mode. 
A read command consists of a 3-letter command followed by the read-request 
symbol "<".  Only one read request is allowed in a single command line.  Any 
parameter may be read at any time. 
 Several characters, such as space, tab, new-line, carriage return, comma, and 
semicolon, are ignored.  They may be included in the command line at any 
place and will have no effect, other than to add to the time required to send the 
command line.  They are not counted in the 80 character limit.  However, they 
must be included in the checksum.  These characters may be used, if desired, 
to provide the meaning of a command line by adding descriptive comments. 
If any error is detected in a command line, none of the commands in the line 
are executed. 
A full list of the commands, parameters, maximum and minimum values, and 
conditions governing when they may be written, is provided in section 4.5. 
A typical valid command line to update the azimuth and elevation point would be: 
 <STX>PTA20.24PTE-14.05E9<ETX>. 
  The calculation of the checksum E9 is given by: 
   <STX>   excluded 
   P       50 hex 
   T       54 hex 
   A       41 hex 
   2       32 hex 
   0       30 hex 
   .       2E hex 
   2       32 hex 
   4       34 hex 
   P       50 hex 
   T       54 hex 
   E       45 hex 
   -       2D hex 
   1       31 hex 
   4       34 hex 
   .       2E hex 
   0       30 hex 
   5       35 hex 
   ----------------- 
   sum    3E9 hex 
4.4 Serial Protocol - Replies from ACU to Host 
 All replies use printable ASCII characters, plus the ASCII control codes as 
follows: 
  STX (start of text, value 02 hex) 
 ETX (end of text, value 03 hex) 
 ACK (acknowledge, value 06 hex) 
 NAK (negative acknowledge, value 15 hex) 
Each complete command line received is answered. Typically the reply will 
start within 2.5 msec of receipt of the last character of the command. 
If an error is detected in the command line, an error message will be returned 
with the control character NAK followed by two ASCII hex characters 
comprising an error code.  Error codes are as follows: 
  (reserved)    01 
 CL_PARITY    02  Parity error in byte in command line. 
 CL_FRAME    03  Framing error in byte in command line. 
 CL_OVERRUN  04  Overrun error in byte in command line. 
 CL_BUFOVFL  05  Receive FIFO overflow. 
 CL_STRLEN    06  Command line more than 80 characters. 
 CL_CHECKSUM  07  Command line checksum error. 
 CL_ILLEGAL   08  Illegal character in command line. 
 CL_CFORMAT  09  Illegal command format. 
 CL_UNKCMD 0A Unknown 3-letter command mnemonic. 
 CL_DATALONG 0B More than 10 characters in value. 
 CL_MLTREAD 0C More than 1 read command in command 
 line. 
 CL_DFORMAT 0D Illegal data format. 
 CL_DATAULIM 0E Data value too large. 
 CL_DATALLIM 0F Data value too small. 
 (reserved)     10    
 CL_NOTREMOTE  11  Controller not in remote and command 
 line attempted to write to parameter 
 which may be changed only in remote. 
 CL_BABBLE    12  Babbling transmitter.  More than 80 
 characters read with no STX. 
        CL_READONLY  13  Read only command and attempted to 
 write. 
 The large number of error messages listed above is intended to assist the user 
in debugging his communications code by pointing to the exact source of the 
problem. 
If there is no error and the command line contained no read messages, the 
response is a single ACK character. 
If there is no error and the command line contained a read message, the 
response is of the format: 
 STX <value> <checksum> ETX 
 where the value may be 1-10 characters including a leading sign and a 
decimal point and the checksum is calculated as above. 

4.5 Command codes and parameters 
4.5.1 General comments 
 Below is a complete description of the command codes and their parameters, 
for use in designing communications programs for the host computer.  In the 
list below, most of the commands are shown with the third letter as x.  The x 
should be replaced by A if the command is for an azimuth parameter or with E 
for an elevation parameter. 
Certain parameters have been adjusted in the factory to work with the 
positioner supplied.  This applies particularly to values for gear ratio, encoder 
pulses per revolution, and gains.  These parameters should not be changed 
unadvisedly. 
Certain parameters may be written only when the controller is in REMOTE 
mode.  This applies to mode, offset, point, and slew-velocity commands.
 Other than these commands, a parameter may be written at any time.  
It is recommended not to change control loop gains unless the positioner is in 
Standby mode. 
When a parameter is written with a normal write command, the change is 
made in RAM only.  Parameter changes may be saved to EEPROM using the 
SAV command with value 1.  Parameters have hard coded default values 
which will exist if the parameter has not been changed.  These default values 
may also be restored by a SAV command with parameter 2.  The values last 
stored in EEPROM may be restored by a SAV command with parameter 3, or 
by cycling power. 
Note: SAV 2 command is for factory use only, since the values restored may 
not be appropriate to the particular positioner to which the controller is 
connected. 
4.5.2 Parameter Limits 
 For each parameter there are maximum and minimum values that will be 
accepted over the communication link.   
  For angles, these values are +/-780 degrees.   
  For velocities, the values are 0 to 10000 deg/sec.   
  For other parameters, the limiting values are given with the 
 command description. 
4.5.3 Alphabetical command listing 
 CBx 
Set value of control word #1.  Bits in control word #1 have the following 
functions: 
  Bit Value    Function 
         -------------------------------------------------------------------------------------------------  
  0 1    0=>CW feedback from motor   = CW motion of axis 
     1=>CCW feedback from motor = CW motion of axis 
  1 2    0=>Positive command for CW rotation of axis. 
     1=>Negative command for CW rotation of axis 
  2 4    Reserved (must be 0) 
  3  8    0=>Shutdown bit = 0 for shutdown 
     1=>Shutdown bit = 1 for shutdown 
  4     16    Reserved (Must be 0). 
  5     32    0=>Limited range of rotation 
     1=>Continuous rotation axis 
  6    64    0=>Normal closed-loop control 
                 1=>Open-loop test mode.  In this case, the position 
feedback is ignored, and the velocity command output is 
10 VDC * RVx/CVx. By changing the value of RVx, a step 
may be produced in the velocity command output for  
testing the response of the velocity loop. 
  7 128    0=>Normal Operation 
     1=>Unused Axis - Always in Shutdown 
  8     256    0=>Normal Operation 
                 1=>Open-loop test mode.  In this case, the position 
feedback is ignored, and the velocity command output is 
a trapezoid based on the parameters RVx, FSx, MAx, 
and RTx.  The slope of the trapezoid is controlled by 
MAx, the height is 10 VDC*RVx/FSx, and the time of the 
flat top is RTx.  The direction of the trapezoid alternates 
each cycle.  This is used for testing the response of the 
velocity loop. 
  Value must be from 0 to 511. 
CCx 
Set value of control word #2.  Bits in control word #2 have the following 
functions: 
  Bit Value    Function 
         ----------------------------------------------------------------------------------------    
  0,1 0-2    0=>Display precision 0.1 degree 
     1=>Display precision 0.01 degree 
     2=>Display precision 0.001 degree 
  2   4    0=>+/-780 deg display 
     1=>0-359.999  or +/-180 deg display 
  3   8    0=>No cable wrap display 
     1=>L,R or U,D cable wrap display 
  4       16    0=>Bidirectional Raster 
     1=>Single Direction Raster 
  5  32    0=>Raster Scan Once 
     1=>Continuous Raster Scan 
  6  64    0=>Soft Step in Point Mode 
     1=>Step at Full Speed in Point Mode 
  7 128    Reserved (Should be 0) 
  8 256    0=>Normal Front Panel Display 
     1=>Front Panel Display Darkened 
  9 512    0=>9600 Baud on 2nd RS-232 Output 
     1=>19200 Baud on 2nd RS-232 Output 
  10 1023    0=>0-359.999 deg display if bit 2 set 
     1=>+/-180 deg display if bit 2 set 
  11 2048    0=>Full precision position on comm link 
     1=>Front Panel position on comm link 
  12 4096    0=>No shutdown in Standby mode 
     1=>Motor amplifiers shutdown in Standby 
           mode 
  Value should be 0-8191. 
CDx 
CGx 
CLx 
CVx 
During a calibrate cycle, the positioner will operate at the go-to-limit velocity 
(CGx) until the clockwise limit switch is activated, the zero indicating pulse is 
detected, or the maximum clockwise calibrate distance (CDx) is passed.  It 
will then return at the calibrate velocity (CVx) until the zero-indicating pulse 
is observed and an index pulse occurs on the encoder.  At that point, the angle 
will be set to equal the zero switch position (CLx).  
CDx sets the maximum clockwise calibrate distance in degrees. 
CGx sets the go-to-limit velocity, in degrees/sec. 
CLx sets the calibrate zero switch position, in degrees. 
EPx 
Motor encoder pulses per revolution of motor. Value must be from 1 to 
1000000, with no decimal point.  Default is 8000. 
FSx 
Full scale axis velocity.  This is the velocity that would be achieved with 10 
VDC velocity command to the amplifier (assuming no limitations due to 
back-EMF).  It is used for converting velocity command outputs from 
degrees/sec to volts. 
FVx 
Front panel slew velocity from maximum joystick motion in coarse mode.  
Value between 0 and 10000 deg/sec.  Value should be about 10-20% greater 
than the actual maximum velocity desired. 
GDx 
GNx 
The gear ratio of each axis is specified as a numerator and a denominator.  
GNx sets the numerator, GDx sets the denominator. Values must be from 1 to 
1000000 for the numerator and 1 to 10000 for the denominator, with no 
decimal point.   
HMx 
Home position.  Value from -720 to +720 degrees.  This is the position that 
the axis goes to when it is placed in home mode. 
ILx 
Integral limit.  Upper limit of velocity command from the integral error term 
in the PI position control loop.  Integral error is defined as: 
 Ki *    ∫ angle error dt 
Where Ki is the parameter specified below under KIx and angle error is the 
difference between actual and target angles.  Units are in deg/sec. Value from 
0 to 50. Lower limit of integral error is the same value with opposite sign.  
Note that the integral error term should be small relative the maximum 
velocity of the system.  It serves primarily to correct for any zero offsets in 
analog components and is updated only when the position command and the 
position feedback are stable and when the closed loop error is within the 
integral window. 
IWx 
Integral window.  The integral error term is updated by the integral gain only 
when the absolute value of the closed loop error is less than this parameter.  
Units are in degrees. 
KDx 
Feedforward  gain in PI position control loop.  The feedforward term provides 
a velocity command output equal to the derivative of the position command 
times the feedforward gain.  Feedforward gain is a pure number.  Normally, it 
is set close to 1. Value is from 0 to 2 
KLx 
Lock gain in PI loop. Units are in 1/sec.  When the positioner has arrived at its 
target position, within the range of the lock window, as specified by the 
parameter LWx, the gain is increased linearly from KPx to KLx as the error 
closes to 0. Value is from 0 to 20, and should normally be greater or equal to 
KPx. 
KPx 
Proportional gain in PI loop. Units are in 1/sec.  Value is from 0 to 20 
KIx 
Integral gain in PI loop.  Units are in 1/sec/sec  Value is from 0 to 20. 
LWx 
Lock window for use of lock gain (KLx) in place of proportional gain (KPx). 
Units are in degrees. 
MAx 
Maximum acceleration/deceleration.  Units are in deg/sec/sec.  Value is from 
0.16 to 10,000.0. 
MDx 
Set operation mode.  Value is as follows: 
   0 - Manual (not allowed) 
   1 - Standby 
   2 - Go to Point 
   3 - Go to Home 
   4 - Slew (Continuous Velocity) 
   5 - Calibrate 
   6 - Raster Scan 
This command is accepted only when the ACU is in REMOTE mode. 
MNx 
Set minimum position.  Units are in degrees.  
Value is from -720 to + 720 degrees. 
MOx 
Set maximum output from D/A chip.  Units are fraction of full scale   
Value is from 0 to 1.0 
MVx 
Set maximum velocity.  Units are deg/sec.  
Value is 0 to 10,000 deg/sec. 
MXx 
Set maximum position.  Units are in degrees. Value is from -720 to + 720 
degrees.  Note that for a continuous rotation axis, the minimum and maximum 
position should be set to less than -190 and greater than +190, respectively. 

OFx 
Set offset.  Units are in degrees.  Value is from  -720 to +720 degrees.  ACU 
must be in REMOTE mode to write offset.  If positioner is moving, the 
velocity is first commanded to zero, and when the positioner stops, the offset 
is entered. 
Note:  Offset for the azimuth may be also be set by the front-panel OFFSET 
pushbutton.  In this case, a save to all parameters is performed.   
PTx 
Set pointing angle. This is the angle which will be used at the target in point 
mode.  Units are in degrees.  Value is from -720 to +720 degrees.  This 
command is accepted only when the ACU is switched to REMOTE mode. 
RCx 
Raster scan center point in degrees. 
RDx 
Read command only.  Read current angle.  Value is in degrees. 
RDS     
Read status word.  Value returned is 0 to 223-1; ie, 0-8388607, consisting of a 
sum of 23 status bits.  Bits in the status word  have the following values and 
meanings (refer to next page): 
  Bit#    Value    Meaning 
    0     1    Azimuth CW Limit Switch Active 
    1     2    Azimuth CCW Limit Switch Active 
    2     4    Azimuth Zero Limit Switch Active 
    3     8    Azimuth Calibrated (see sec 2.1, CAL 
 function) 
    4    16    Azimuth Stuck (Full current, no motion) 
    5         32    Azimuth Software CW Limit Active 
    6         64    Azimuth Software CCW Limit Active 
    7        128    Azimuth Encoder Fault 
    8        256    Elevation CW Limit Switch Active 
    9        512    Elevation CCW Limit Switch Active 
    10       1024    Elevation Zero Limit Switch  Active 
    11       2048    Elevation Calibrated 
    12       4096    Elevation Stuck (Full current, no 
 motion) 
    13       8192    Elevation Software CW Limit Active 
    14      16384    Elevation Software CCW Limit  Active 
    15      32768    Elevation Encoder Fault 
    16      65536    Front Panel Switch Flickering 
    17     131072  EEPROM Memory Fault Detected 
    18     262144  Remote Mode 
    19     524288  Azimuth Joystick A/D Fault 
    20    1048576  Elevation Joystick A/D Fault 
    21    2097152  Azimuth Calibration Done 
    22    4194304  Elevation Calibration Done 
    23-31             Unused        
RRx   
Raster scan range in degrees 
RTx 
RTA is the Raster Scan time delay at end of each azimuth scan in seconds.  If 
bit #8 in control word #1 is set, RTx is the duration of the flat top of the 
trapezoidal open-loop velocity command output. 
RVx 
RVx is the Raster Scan velocity in deg/sec.  If bit #6 or bit #8 in control word 
#1 is set, RVx is the open loop velocity command output (bit #6) or the open 
loop velocity command output during the flat top of the trapezoid (bit #8). 
SAV 
Save/Restore commands.  All other commands perform reads and writes on 
parameters in static RAM.  Any changes made in this way will be lost when 
power is turned off unless they are saved to the EEPROM non-volatile 
memory. 
On powerup, if values exist in EEPROM they are used.  If the EEPROM has 
never had values stored in it, or if a checksum error is found, the hard-coded 
default values are used. 
A SAV command with a value of 1 causes present values in RAM to be saved 
to EEPROM. 
A SAV command with a value of 2 causes default values to be restored to 
RAM.  Note that any changes made and not yet saved to EEPROM are now 
lost.   However, any values in EEPROM are still there  and will be used next 
time power is cycled.  Note that default values may be stored to EEPROM by 
a SAV 2 followed by a SAV 1 command. 
A SAV command with a value of 3 causes EEPROM values to be restored to 
RAM. 
STI 
Interval between status outputs on J6.  Units are 1=2.5 msec.  For example, 
for a status interval of 200 msec, STI parameter should be set to 80. 
SVx 
Slew velocity command.  This sets the velocity in degrees/sec which will be 
used when Slew Mode is selected.  This command is accepted only when the 
ACU is in REMOTE. 
UTx 
Maximum update time command.  Sets time interval, in seconds, used to 
activate the extrapolation algorithm for following a trajectory.  If two 
consecutive time intervals are less than the maximum update time, the 
extrapolation algorithm is activated.  Value must be between 0 and 10 
seconds. 
5 TROUBLESHOOTING 
 Problem: No display, no LEDs, no motion on powerup 
Check: • Is Fuse F1 OK? 
    • Is Mains Select Switch in proper 
 position? 
    • Is AC Power Cord connected well? 
Problem: Display OK but neither axis operates 
Check:   • Is Safe/Operate switch on positioner in OPERATE 
 mode? 
  • Are cables W1 and W2 connected properly to the 
 controller and the positioner? 
Problem: Azimuth axis does not operate      
Check:    • Is Fuse F2 OK? 
Problem: Elevation axis does not operate      
Check: • Is Fuse F3 OK? 
Problem: Front Panel does not operate      
Check:   • Is Red Local LED lit? If not, press 
 REMOTE/LOCAL switch to place in LOCAL mode.  
 Red LED should light and Green LED should be  
 turned off. 
Problem: Positioner motion is very slow      
Check:    • FINE/COARSE switch should be in COARSE 
 position for rapid motion. 
Problem: Azimuth position reading is not correct after calibrate 
Check:   • After calibrate, place the controller in LOCAL 
 mode by pressing the LOCAL/REMOTE button,  
 point the Positioner in the azimuth direction where 
 a reading of 0 is desired and press the offset 
 button. 
Problem: Azimuth axis creeps when Joystick is in zero 
 position   
Solution: • Adjust small zeroing lever in the horizontal 
 direction until no creep occurs. 
Problem: Elevation axis creeps when Joystick is in zero  
 position   
Solution:   • Adjust small zeroing lever in the vertical direction 
 until no creep occurs. 
6 MAINTENANCE 
6.1 Amplifier Adjustment 
 Verify the following settings: 
 • T1 is at the maximum CW position. 
 • T2 is at the midpoint of the potentiometer range. 
6.2 Voltage Tests 
 With respect to GND (TB1, pin 7), verify the following DC 
voltages: 
 -12V +/- 0.3V   at TB1 (6) 
 +5V +/- 0.25V at TB1 (5) 
 +12V +/- 0.3V at TB1 (4) 
With respect to GND (TB1, pin 8), verify the following DC voltages: 
  130V +/- 5V    at TB1 (9) 

APPENDIX A 
 AL-1642-3JB 
Host Software User's Guide 

 1.  SOFTWARE 
 The AL-1642-3JB Host Software is provided on an "as is basis", as an aid for the user, with 
no expressed or implied warrantees or guarantees of any kind.   
The following four files comprise the host software:  
1) EGAVGA.BGI  
 Loadable graphics interface file for VGA graphics routines. 
 2) KBRG.CF_   
 Configuration file for the host software. 
3) KBRG.ST_ 
 Configuration file for the host software. 
 4) HOST.EXE 
Executable code for the host software. 
 2.  INSTALLATION 
 1) Copy the above four files into a directory on the hard disk (any name for the directory 
is acceptable). 
 2) Use the following procedure to run the software: 
 1) If COM1 is configured for communications, type HOST 1 and press 
ENTER key. 
 2) If COM2 is configured for communications, type HOST 2 and press 
ENTER key. 
 3) The Main Screen will be accessed (refer to Figure A-1) 
 Note: The software has been run on a range of computers; from a 386DX 
operating at 33 MHz, without floating point coprocessor, running 
under DOS 5.0 to a Pentium II operating at 400 MHz running in a 
DOS window under Windows 95.  Minimum computer requirements 
have not been established, but most likely a PC-XT or a lower 
compatible computer will not be capable of running the software. 
 3.  MAIN SCREEN  (Refer to Figure A-1) 
 The Main Screen is divided into three sections:  
1) Axes Numerical Display 
2) Status Flag Display 
3) Function Key Titles. 
The Axes Numerical Display section shows four parameters for each axis:   
Point Command, Slew Velocity Command, Mode Command and Position Received. The 
displayed field shows the last command sent for each of these parameters, as received from 
the positioner. 
The Status Flag section of the main screen shows which flags are set from the RDS command 
to the AL-1642-3JB, along with titles to show their meaning. 
The Function Keys permit entry to the azimuth and elevation configuration screens (F1, F2; 
respectively), setting of positioner azimuth and elevation modes (F3, F4; respectively), 
updating target point for point mode and slew velocity for slew mode (F7), and exiting from 
the program (F8). 
Before entering azimuth or elevation go-to-point mode, using F3 or F4, respectively; F7 
should be utilized to introduce a target point, since otherwise the value of the target point will 
depend on the previous mode and last operation performed in this mode, and will not 
necessarily be that displayed on the screen under Azim-Point-Command or Elev-Point-
Command. 
When azimuth mode or elevation mode CALIBRATION is selected, using F3 or F4, 
respectively; the above sequence is begun again each time the command to enter the 
calibration mode is initiated. 

Figure A-1:  Main Screen 
Azim  Azim     Azim    Azim     Elev       Elev     Elev     Elev 
Point      Slew    Mode    Position  Point     Slew   Mode    Position 
Command Command Command Received Command  Command Command Received 
0.000 0.000 POINT 0.000 0.000 0.000 POINT 0.000 
 STATUS FLAGS 
 AZ_CW_LIM   = 0  AZ_STUCK      = 0       EL_CW_LIM   = 0  EL_STUCK      = 0 
 AZ_CCW_LIM  = 0  AZ_CW_SLIM    = 0       EL_CCW_LIM  = 0  EL_CW_SLIM    = 0 
 AZ_ZERO_LIM = 0  AZ_CCW_SLIM   = 0       EL_ZERO_LIM = 0  EL_CCW_SLIM   = 0 
 AZ_CALIBR'D = 1  AZ_ENC_FAULT  = 0       EL_CALIBR'D = 1  EL_ENC_FAULT  = 0 
SWTCHFLT=0 EEPRMFLT=0 AZADCFLT=0 ELADCFLT=0 REMOTE=1 AZCALDONE=1 ELCALDONE=1 
1 AZIM     2 ELEV     3 AZIM    4   ELEV    5        6        7 SETPOINT 8 PROGRAM 
CONFIG      CONFIG     MODE      MODE                          SLEW VEL   EXIT 
 4.  CONFIGURATION SCREENS  (Refer to Figures A-2, A-3 and A-4) 
 Each axis (azimuth or elevation) has its own set of configuration parameters.   For a system 
that has never been configured, a set of default parameters are coded into the controller 
software.  In addition, an EEPROM exists which allows the user to save the parameters he 
has configured.  If parameters have been saved, they will be read from the EEPROM at 
powerup and used instead of the default parameters.  Note that azimuth and elevation 
parameters are saved together; i.e., it is not possible to save the parameters for one axis only. 
To configure azimuth parameters, press the function key F1.  The azimuth configuration 
screen will be loaded (refer to Figure A-2).  Parameters are configured by entering the item 
number to the left of the parameter, and then entering the desired value.  Values that are too 
large, too small,  or of incorrect format will be rejected with an error message displayed, and 
the parameter will retain its previous value.   
To save the new parameter values, enter 55 from the keyboard.  The software then initiates a 
command SAV1 and waits until the controller has reset the SAV parameter to zero, at which 
time a message "Save Confirmed" is displayed. 
To restore the default configuration values for the parameters, enter 66.  The software 
initiates a command SAV2 and then displays the default values of the parameters.  Note that 
the parameter default configuration is now restored to active use, but this does not affect the 
configurations that are stored in EEPROM.  Also note that the default configuration may not 
be suitable for the positioner and load presently interfaced with the controller.  (Therefore, 
care should be exercised when using the "66" command). 
To restore the parameter configuration held in the EEPROM, enter 77. The software then 
initiates the command SAV3 which restores the parameters to their last saved values. 
To exit the Configuration screen and return to the main screen, enter 88. 
To configure the Elevation parameters, press function key F2 on the main screen.     A 
screen that is identical to the azimuth configuration screen, except for the title, is accessed 
(refer to Figure A-3). 
Figure A-4 shows the parameters on the azimuth or elevation configuration screen, 
correlated with the software remote command codes (refer to paragraph 4.5 in the main 
section of this manual). The lower case ‘x’ is to be replaced by either A or E for azimuth or 
elevation axis, respectively. 

Figure A-2:  Azimuth Configuration Screen – Default Parameter Values 
Azim Pedestal Parameters                Azim Control Parameters 
  1. Gear Ratio Numerator...       36 21. Maximum Acceleration.. 12.000 
  2. Gear Ratio Denominator.        1 22. Maximum Velocity...... 36.000 
  3. Encoder Pulses/Rev.....     8000 23. Go-to-Limit Velocity.. 18.000 
  4. Control Bits Word #1...       32 24. Calibrate Velocity.... 18.000 
  5. Control Bits Word #2...     2149 25. Front Panel Velocity.. 36.000 
  6. Maximum Angle.......... +380.000 26. Low Kp-Proport Gain...  0.997 
  7. Minimum Angle.......... -380.000 27. High Kp-Lock Gain..... 3.966 
  8. Home Position..........   0.000 28. High Kp Window........  0.050 
  9. Zero Switch Position...   0.000 29. Kd-Differential Gain..  1.000 
 10. Offset.................   0.000 30. Ki-Integral Gain......  0.244 
 11. Special Sts Interval...       80 31. Integral Limit........  5.000 
 12. Full Scale Velocity....  42.000 32. Integral Gain Window. 500.000   
 13. Maximum D/A Chip Output   1.000 33. Maximum Update time... 0.000 
 14. Max CW Cal Movement.... 380.000 34. Raster Center......... 50.000   
 55. SAVE CONFIG TO EEPROM               35. Raster Range.......... 80.000 
 66. RESTORE DEFAULT CONFIG              36. Raster Vel............ 18.000 
 77. RESTORE EEPROM CONFIG               37. Raster Step...........  0.000 
 88. EXIT                                38. Raster Scan Delay.....  0.000 
Figure A-3:  Elevation Configuration Screen – Default Parameter Values 
ELEV Pedestal ParamS               ELEV Control Parameters 
 1. Gear Ratio Numerator....      36  21. Maximum Acceleration..  12.000 
 2. Gear Ratio Denominator..       1  22. Maximum Velocity......  18.000 
 3. Encoder Pulses/Rev......    8000 23. Go-to-Limit Velocity..  3.000 
 4. Control Bits Word #1....       0   24. Calibrate Velocity....  10.000 
 5. Control Bits Word #2....    2145  25. Front Panel Velocity..  18.000 
 6. Maximum Angle........... 182.000  26. Low Kp-Proport Gain...  0.997 
 7. Minimum Angle........... . -2.000  27. High Kp-Lock Gain.....  4.000 
 8. Home Position...........   0.000 28. High Kp Window........  0.050 
 9. Zero Switch Position....   0.000 29. Kd-Differential Gain..   1.000 
10. Offset..................   0.000 30. Ki-Integral Gain......  0.244 
11. Special Sts Interval....      80  31. Integral Limit........  5.000 
12. Full Scale Velocity.....  69.000 32. Integral Gain Window   500.000   
13. Maximum D/A Chip Output.   0.700 33. Maximum Update time...  0.000 
14. Max CW Cal Movement.....   20.000 34. Raster Center......... 20.000 
55. SAVE CONFIG TO EEPROM               35. Raster Range.......... 40.000 
66. RESTORE DEFAULT CONFIG              36. Raster Vel............ 18.000 
77. RESTORE EEPROM CONFIG               37. Raster Step...........  5.000 
88. EXIT                                38. Raster Scan Delay.....  0.000 
Note: 
The above configuration screens list the DEFAULT values of the pedestal and control parameters for 
the Azimuth and Elevation Axes. Do not use these parameter values, since they may not be suitable 
for the positioner. Refer to the following “Installation and Calibration Procedure” configuration 
screens (Figures A-5 thru A-8) to determine which pedestal and control parameter values need to be 
adjusted. 

Figure A-4:  Azimuth/Elevation  Configuration Screen correlated with remote command codes 
  Azim/Elev Pedestal Parameters          Azim/Elev Control Parameters 
  1. Gear Ratio Numerator....     GNx    21. Maximum Acceleration..MAx 
  2. Gear Ratio Denominator..     GDx    22. Maximum Velocity......MVx 
  3. Encoder Pulses/Rev......     EPx    23. Go-to-Limit Velocity..CGx 
  4. Control Bits Word #1....     CBx    24. Calibrate Velocity....CVx 
  5. Control Bits Word #2....     CCx    25. Front Panel Velocity..FVx 
  6. Maximum Angle...........     MXx    26. Low Kp-Proport Gain...KPx 
  7. Minimum Angle...........     MNx    27. High Kp-Lock Gain..   KLx 
  8. Home Position...........     HMx    28. High Kp Window........LWx 
  9. Zero Switch Position....     CLx    29. Kd Differential Gain..KDx 
 10. Offset..................     OFx    30. Ki-Integral Gain......KIx 
 11. Special Sts Interval....     STI    31. Integral Limit........ILx 
 12. Full Scale Velocity.....     FSx    32. Integral Gain Window..IWx 
 13. Maximum D/A chip Output.     MOx    33. Maximum Update time.  UTx 
 14. Max CW Cal Movement.....     CDx    34. Raster Center.........RCx 
 55. SAVE CONFIG TO EEPROM       SAV1    35. Raster Range..........RRx 
 66. RESTORE DEFAULT CONFIG      SAV2    36. Raster Vel............RVx 
 77. RESTORE EEPROM CONFIG       SAV3    37. Raster Step...........RSx 
 88. EXIT                                38. Raster Scan Delay.....RTx 

5.  INSTALLATIONS AND CALIBRATION PROCEDURE 
(Refer to Figures A-5 thru A-8) 
 1) Install the positioner in an indoor environment. 
2) Before connecting the controller to the positioner, use the Host computer program to 
verify that the configuration parameters installed in the controller memory are as 
listed in the applicable figure A5 thru A-8. 
 3) Connect the cables between the controller and the positioner. 
 4) Before installing the antenna and the counterweights, turn on the controller and verify 
that the positioner is moving smoothly and is completing the calibration procedure. 
Then, use the manual joystick to check the elevation software limits. (The down limit 
should be –2 degrees, and the upper limit should be 110 degrees). 
 5) Manually point the elevation axis to 90 degrees. 
 6) Install the arms on the positioner. 
 7) Install the correct number of counter weights on the back of the antenna arms as 
previously determined for the antenna unit. 
 8) Install the antenna on the positioner. 
 9) Point the antenna to 0 degree.  
 10) Connect a dc current probe on the F3 wire, and measure the current. The current 
should be between 0 +/-0.5 amps. If the current exceeds this value, correct the 
antenna balance by adjusting the counterweights (adding or removing 
counterweights). 
 After completing steps 1 through 10, you can operate the positioner under load. 
 CAUTION 
You must observe positioner movement for both axes and verify that the operation is smooth, 
with no oscillations or jerking. In case of un-smooth movement, stop the positioner operation 
IMMEDIATELY and recheck the applicable configuration parameters and the antenna 
balance. 

11) Rotate the elevation axis between 0 degrees and 180 degrees. Verify that the current 
on the F3 wire does not exceed 1.0 amp. (When changing the rotation direction, more 
current may be present for a short duration of time). 
 12) Rotate the azimuth axis in continuous rotation. Verify that the current on the F2 wire 
does not exceed 1.0 Amp. 
 13) Operate the azimuth and elevation axes in POINT mode. Verify that both axes arrive 
at the desired position, with smooth deceleration and no overshoot. If overshoot 
occurs, configuration parameter 12 (Full Scale Velocity) may be increased or 
decreased up to 5 percent of the value.  
 CAUTION 
Do not exceed the +/-5% tolerance for the values stated in Step 13. 

 6.  AL-4017-1EBS-B Positioner Configuration Parameters 
 Note: 
The following parameters are listed as they appear on the computer screen. 
Figure A-7:  Azimuth Configuration Screen for AL-4017-1EBS-B Positioner 
Azim Pedestal Parameters                Azim Control Parameters 
  1. Gear Ratio Numerator...       36 21. Maximum Acceleration.. 12.000 
  2. Gear Ratio Denominator.        1 22. Maximum Velocity...... 36.000 
  3. Encoder Pulses/Rev.....     8000 23. Go-to-Limit Velocity.. 18.000 
  4. Control Bits Word #1...       32 24. Calibrate Velocity.... 18.000 
  5. Control Bits Word #2...     2149 25. Front Panel Velocity.. 36.000 
  6. Maximum Angle.......... +380.000 26. Low Kp-Proport Gain...  0.997 
  7. Minimum Angle.......... -380.000 27. High Kp-Lock Gain..... 3.966 
  8. Home Position..........   0.000 28. High Kp Window........  0.050 
  9. Zero Switch Position...   0.000 29. Kd-Differential Gain..  1.000 
 10. Offset.................   0.000 30. Ki-Integral Gain......  0.244 
 11. Special Sts Interval...       80 31. Integral Limit........  5.000 
 12. Full Scale Velocity....  42.000* 32. Integral Gain Window. 500.000   
 13. Maximum D/A Chip Output   1.000 33. Maximum Update time... 0.000 
 14. Max CW Cal Movement.... 380.000 34. Raster Center......... 50.000   
 55. SAVE CONFIG TO EEPROM               35. Raster Range.......... 80.000 
 66. RESTORE DEFAULT CONFIG              36. Raster Vel............ 18.000 
 77. RESTORE EEPROM CONFIG               37. Raster Step...........  0.000 
 88. EXIT                                38. Raster Scan Delay.....  0.000 
*  This number may vary by +/-5%, depending on the tacho voltage level. 
CAUTION 
Do not exceed the +/-5% tolerance for the value stated in Parameter No. 12 (Full Scale Velocity). 
Oscillation may result from exceeding the 5% tolerance.  

Figure A-8:  Elevation Configuration Screen for AL-4017-1EBS-B Positioner 
ELEV Pedestal ParamS               ELEV Control Parameters 
 1. Gear Ratio Numerator....      36  21. Maximum Acceleration..  12.000 
 2. Gear Ratio Denominator..       1  22. Maximum Velocity......  18.000 
 3. Encoder Pulses/Rev......    8000 23. Go-to-Limit Velocity..  3.000 
 4. Control Bits Word #1....       0   24. Calibrate Velocity....  10.000 
 5. Control Bits Word #2....    2145  25. Front Panel Velocity..  18.000 
 6. Maximum Angle........... 182.000  26. Low Kp-Proport Gain...  0.997 
 7. Minimum Angle........... . -2.000  27. High Kp-Lock Gain.....  4.000 
 8. Home Position...........   0.000 28. High Kp Window........  0.050 
 9. Zero Switch Position....   0.000 29. Kd-Differential Gain..   1.000 
10. Offset..................   0.000 30. Ki-Integral Gain......  0.244 
11. Special Sts Interval....      80  31. Integral Limit........  5.000 
12. Full Scale Velocity.....  69.000* 32. Integral Gain Window   500.000   
13. Maximum D/A Chip Output.   0.700 33. Maximum Update time...  0.000 
14. Max CW Cal Movement.....   20.000 34. Raster Center......... 20.000 
55. SAVE CONFIG TO EEPROM               35. Raster Range.......... 40.000 
66. RESTORE DEFAULT CONFIG              36. Raster Vel............ 18.000 
77. RESTORE EEPROM CONFIG               37. Raster Step...........  5.000 
88. EXIT                                38. Raster Scan Delay.....  0.000 
*  This number may vary by +/-5%, depending on the tacho voltage level. 
CAUTION 
Do not exceed the +/-5% tolerance for the value stated in Parameter No. 12 (Full Scale Velocity). 
Oscillation may result from exceeding the 5% tolerance.  

APPENDIX B 
AL-1642-3JB (BS-104435) CONTROLLER DRAWINGS: 
DRAWINGS 
Figure B-1: WIRING DIAGRAM   - Dwg. No. BS-104435-1 
Figure B-2: TOP ASSEMBLY   - Dwg. No. BS-104435-2 
Figure B-3: FRONT PANEL   - Dwg. No. BS-104435-3 
Figure B-4: REAR PANEL   - Dwg. No. BS-104435-4 
Figure B-5: BLOCK DIAGRAM   - Dwg. No. BS-104435-5 
Figure B-1: WIRING DIAGRAM    -  Dwg. No. 19-0350 
Figure B-2: TOP ASSEMBLY   - Dwg. No. 19-0354-9/2 
Figure B-3: FRONT PANEL   - Dwg. No. 19-0351-9/2 
Figure B-4: REAR PANEL   - Dwg. No. 19-0352-9 

Figure B-5: BLOCK DIAGRAM    -  Dwg. No. 20-0094 

RDACS User’s Guide  August 2000
i

RDACS User’s Guide  August 2000
ii
Table of Contents 
1. Introduction……………………………………………………………………………….. 
1 
2.  RDACS Terminal Window………………………………………………………………. 
2 
3. RDACS Config…………………………………………………………………………….  3 
3.1 File Pull-Down Menu……………………………………………………………………..  3 
3.2 Connect Commands……………………………………………………………………..  4 
3.3 A-Scope Commands…………………………………………………………………….. 5 
3.4 Control Commands………………………………………………………………………  8 
3.5 Configuration Commands……………………………………………………………… 17
4. Configuration Commands……………………………………………………………….. 36
5. Installing RDACS…………………………………………………………………………..  39
6. The radacs.ini Configuration File……………………………………………………….  41
6.1 Start-Up Section………………………………………………………………………….  45
6.2 Master Section……………………………………………………………………………  50
6.3 Site Section………………………………………………………………………………..  53
6.4 RadPgmN Section………………………………………………………………………..  57
6.5 Antenna Sections………………………………………………………………………...  63
6.6 LevelN Section…………………………………………………………………………… 67
6.7 ModeN Section…………………………………………………………………………… 70
6.8 AntennaCmds Section………………………………………………………………….. 91

RDACS User’s Guide  August 2000
iii
Preface 
This manual describes the operating procedures for Baron Service’s RDACS software 
program that is delivered with the Neighborhood Radars™ 
Document Organization 
The information in this manual is organized as follows: 
 Section 1 describes the RDACS Terminal Window, which acts as the radar 
system’s log and provides a few controls. 
 Section 2 describes the RDACS Config utility, which lets you perform a 
limited number of system controls from the Radar Control dialog box. 
 Section 3 is a step-by-step procedure for accessing RDACS controls while 
operating FasTrac. 
 Section 4 describes the installation instructions for RDACS. 
Related Documentation 
The following manual provides in-depth information about RVPtty: 
RVP7™ Digital IF Receiver and Doppler Signal Processor User’s Manual. 
Describes the operating and troubleshooting procedures for SIGMET, Inc’s. RVP7 
Doppler Signal Processor. 
Type Faces 
Italic: Indicates a document title, the first occurrence of a new term, a directory or 
file name, or a system response that explains what the system is doing. For 
Example: The monitor displays current parameters. 

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Bold: Indicates an item in the graphical interface, such as the OK button or a 
command button. 
Courier: Indicates information you type. For example: Set the signal 
processor parameters by typing: SOPRM 
Symbols 
The following document conventions are used throughout this manual: 
Information that is not critical to system operation but describes useful 
procedures or information that will optimize system operation. 
Very important about a command or a procedure. 
Critical instructions that must be followed to prevent injury or loss of 
data. 

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Keyboard Conventions 
ALT  
Alternate key. For example, ALT+x means hold down the Alternate key 
and press x. 
CTRL  
Control key. For example. CTRL+c means hold down the Control key 
and press c. 
DEL  
Delete key. 
Enter  
Return/enter key. 
ESC  
Escape key. 
SHIFT  
Shift key. 
TAB  
Tab key. 

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Terminology 
Click 
To position the pointer on the screen, and then to press and quickly 
release the left mouse button. 
Double Click 
To quickly press and release a mouse button twice without moving 
the mouse. This action is used as a shortcut for common actions, 
such as activating an icon, opening a file, or selecting a word or a 
graphic element. 
Drag 
To press and hold a mouse while moving the mouse. This action is 
used to identify a range of objects, to move objects, or to resize 
objects. 
Enter 
To input information by typing or by using the mouse. 
Identify 
To locate an element on the screen either by clicking it or by typing 
the name. 
Press and hold 
To press and hold down a mouse button to perform an action, such 
as resizing a window. 
Scroll 
To move through text or graphics 
Select 
To click a button, a text box, an item in a list, or some other item on a 
dialog box, menu, or window. 
Type 
To key in data. To complete this action, you may also need to click 
OK, press ENTER, or press TAB. 
What to Expect from this Document 
This document describes how to install, start, and run the RDACS program. 

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1.   Introduction 
This manual describes the Radar Acquisition and Control System (RDACS), which gives 
users remote control over many radar system operations. The remainder of this manual 
is comprised of four main sections: 
1.  The RDACS terminal window, which is accessed by Start    BSI   RDACS. 
2.  The Radar Control dialog box, which is accessed by Start    BSI   Config 
RDACS. 
3.  The RDACS window that is installed in FasTrac. 
4.  The RDACS installation instructions.

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2. RDACS Terminal Window 
The RDACS terminal window acts as the radar system’s log and provides few controls. 
The main display lists the time and type of radar system commands. The commands can 
be issued from Config RDACS or from FasTrac real-time operations. The following 
window displays when you select Start    BSI   RDACS. (Start is located next to the 
taskbar on bottom of your terminal screen.) 
The File menu has only one subcommand, Exit. 
The Misc menu has three subcommands: Gparm, Log scans, and List users. 
1.  Gparm accesses the status information for the radar system. 
2.  Log scans displays information about a complete antenna scan similar to the 
following: Scan complete: 39 seconds, 361 rays, 0 too big, small 1.0, large 
1.0 
3.  List users displays the following information about users who are remotely 
logged into your system’s RDACS: ID, State, User name, Address, Log-In 
time, and Log-Out time. 

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3. RDACS Config 
The RDACS Config utility lets you perform a limited number of system controls from the 
Radar Control dialog box, which is accessed by selecting Start    BSI   Config 
RDACS. 
3.1 File Pull-Down Menu 
The File pull-down menu has only two options: About and Exit. Select File   About to 
open a message box that indicates the name of the software package, the version 
number, and the copyright date. Click OK to dismiss the message box. 
Select File    Exit to terminate the RDACS Config session. 

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3.2 Connect Commands 
The Connect commands let you remotely view and control another site’s RDACS. 
Select Connect    Disconnect to end remote control mode. 
A connect to RDACS dialog box, similar to the one shown below, displays when you 
select Connect    Connect. You must know the server name or address, your user 
name, your password, and the port designator to connect remotely to RDACS. See your 
System Administrator for the required inputs. 
A Connect to RDACS dialog box, similar to the one shown below, displays when you 
select Connect    Auto connect. This dialog box lets you log onto the specified server 
to remotely view and control RDACS. The controls on this dialog box are similar to the 
Connect to RDACS dialog box, except you automatically are connected to the specified 
server when you start up RDACS and you cannot save your password. 

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3.3 A-Scope Commands 
The A-Scope commands let you configure the A-Scope presentation of return data, in 
signal strength and in either distance or in time. You can use the A-Scope commands to 
display three types of radar data (reflectivity, velocity, and spectrum width) and to set the 
display limits. 
3.3.1 A-Scope Settings 
The A-Scope displays the radar data, where the horizontal axis (X) displays time and the 
vertical axis (Y) displays signal strength. The A-Scope Settings command lets you 
configure the display shown when you select A-Scope    Enable. 
The following, double-tabbed dialog box displays when you select Oscilloscope   
Settings: 

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This Base Products section of this dialog box lets you select which radar products will 
be shown on the A-Scope display. When you select a radar product, you must either 
select the Data shown in display level units’ option to enable the default values or key 
in the Low Y and High Y values. 
Control Description 
Reflectivity 
Enables the computer algorithms that measure the linear 
radar reflectivity factor (z) in m6/m3. 
Velocity 
Enables the computer algorithms that measure the winds in 
the atmosphere. 
Spectrum Width 
Enables the computer algorithms that transform time-series 
data into the frequency domain. In other words, it 
determines the average frequency as well as the 
distribution of frequencies, thus providing data about storm 
turbulence. 
Data shown in display 
level units 
You must select this option to enable Default option. 
OK 
Accepts your changes, and returns you to the main RDACS 
dialog box. 
Cancel 
Ignores any changes, and returns you to the main RDACS 
dialog box. 
The X Scale portion of the dialog box controls the A-Scope’s horizontal display. You 
must either select the Auto Scale option or specify the Low X and High X values. 

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Control Description 
Auto Scale 
Automatically controls the low and high range for the 
horizontal axis. When selected, the Low X and High X 
fields are disabled. 
Low X 
Specifies the lowest range for the horizontal axis. 
High X 
Specifies the highest range for the horizontal axis. 
Units 
Specifies the unit for the horizontal axis measurements: 
miles, nautical miles, kilometers, or microseconds. 
OK  
Accepts your changes, and returns you to the main RDACS 
dialog box. 
Cancel 
Ignores any changes, and returns you to the main RDACS 
dialog box. 

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3.3.2 A-Scope Display 
An A-Scope Display, similar to the one pictured below, appears when you select A-
Scope   Enable. It is a real-time display, reflecting the parameters you set under A-
Scope Settings. Select A-Scope   Disable to remove the display and to return to the 
main Radar Control dialog box. 
3.4 Control Commands 
The Control Commands let you set most of the radar’s controlling parameters, as 
described in the following subsections. Remember, some of the controls can also be 
changed by: 
1. Editing the rdacs.ini file. 
2.  Performing real-time system manipulations in the FasTrac program. 
In either case, the last issue change is the one under which the radar system operates.

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3.4.1 Quick Control 
A Quick Control dialog box, similar to the one shown below, displays when you select 
Control    Quick.  Observe the RDACS display when you issue commands form this 
dialog box, and verify that the system is operating as expected. 
Control Description 
Range 
Defines the maximum distance from the radar antenna to 
the target. You may specify the range measurement in 
miles, kilometers, or nautical, miles. If you have a single or 
double-pulse Doppler radar, range is usually 75 miles. If 
your system is in Log mode, range is usually 300 miles. 
Remember, the lower the range, the higher the resolution 
for closer targets. If you set a range that is greater than the 
maximum allowed for your radar type, RDACS uses the 
maximum valid range and displays the correct value. 

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Control Description 
Skip 
Sets the radar sampling skip distance in miles. For 
example, a value of 2.5 means that data sampling begins 
2.5 miles from the radar. Use this option to remove the 
display of the strong signal that is received just after the 
radar pulse is transmitted. A typical value for Skip lies 
between 0.5 to 5.0 miles (the default value is 1.0). 
Mode 
Controls the system mode as selected from the pull-down 
menu: Not all modes are available for all radars. Only the 
available modes are displayed. 
Power Down turns off the radar electronics. It may take 
several minutes before the radar cools and the power is 
removed. 
Standby turns off the transmitter (it no longer radiates), 
while the radar electronics remain on. 
Log places the radar in long-pulse mode, which is up to 
300 miles in range and provides no velocity product. 
Log + Turb places the radar in log mode, and the system 
displays turbulence from the receiver data. 
Long Pulse places the radar in long pulse mode, which is 
up to 300 miles in range. 
Single PRF places the system in single-pulse Doppler 
mode. Range is set to 75 miles and the pulse tolerance is 
set to +/- 16 µs. 
VHD places the system in Very High Definition (dual-pulse) 
Doppler mode. Range is set to 49 miles, and pulse 
tolerance is set to +/- 38 µs. 
Dual PRF places the system in dual-pulse Doppler mode. 
Range is set to 75 miles, and the pulse tolerance is set to 
+/- 32 µs. 
No Radiate turns off your radar system. It may take several 
minutes before the transmitter cools and power is removed. 

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Control Description 
Antenna 
Defines the antenna Scan mode: PPI, Stop, Sector, or 
RHI. PPI (plan position indicator) mode displays a 360-
degree sweep in azimuth at the specified elevation angle. 
(This is the normal operating modes) 
Stop scans weather only within the specified azimuth and 
elevation levels. This mode is useful for investigating a 
particular storm cell. 
RHI (range-height indicator) shows the distance from the 
radar at the specified azimuth angle and displays the height 
above the radar on the vertical axis, from El 1 to El 2. (Note 
that RHI exaggerates the vertical size of an echo, giving a 
distorted impression of the actual storm. The angular 
resolution of the radar increases as the beamwidth 
decreases, so the narrower the beam, the lesser the size of 
the echo.) 
Sector performs a pie-shaped track at the set azimuth, 
within the specified span, at the set elevation level. 
Apply 
Puts the new specifications into operations, and returns you 
to the main Radar Control window. 
Close 
Ignores any changes you have made, and returns you to 
the Main Control window. 
3.4.2 Extended Control 
The Extended Control dialog box is similar to the Quick Control dialog box described in 
Section 1.4.1 except you have two additional options: Preferred Product and Duration. 

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Preferred Product lets you specify which algorithms the computer applies to the 
decluttered, dealiased, and range-unfolded return data to produce the selected product. 
You can select the following items from the pull-down menu: No preference, Log 
intensity, Linear intensity, Velocity, or Turbulence. 
1.  No preference indicates that clean, quality-checked return data will be 
displayed. 
2.  Log Intensity measures reflectivity in logarithmic values. Z is the logarithmic 
reflectivity factor measured in units of dBZ (decibels relative to a reflectivity 1 
mm6/m3 ) 
3.  This is a convenient method for compressing reflectivity measurements to 
numbers that are more convenient than the larger values of the 
corresponding linear intensity measurements. 
4.  Linear intensity measures the linear radar reflectivity factor (z) in m6/m3. 
5.  Velocity measures the winds in the atmosphere. 
6.  Turbulence measures velocity variances that exceed set thresholds. The 
higher the variance, the greater the turbulence. 
7.  Duration specifies the transmitter’s pulse duration measured in the specified 
units: seconds or cycles. 

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A dialog box similar to the one shown below, displays when you select Control   
Extended: 
3.4.3 Program Control 
A dialog box similar to the one shown below, displays when you select Control   
Program: 

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Control Description 
Program List 
Displays saved programs 
OK 
Accepts your changes, and returns you to the main RDACS 
dialog box. 
Cancel 
Ignores any changes, and returns you to the main RDACS 
dialog box. 
Edit 
Lets you modify program parameters. 
Insert 
Lets you introduce a new program. 
Delete 
Deletes the selected program. 
Move Up 
Moves you up through the program list. 
Move Down 
Moves you down through the program list. 
3.4.4  Inputs and Outputs 
The Input/Output control combines several functions: 
1. The User Defined options let you test the Digital Signal Processor’s input 
and output buses. If everything is working correctly, the Fault indicator will 
remain unlit. 
2. The Radiate command lets you turn on the transmitter. 
3. The Fault, Filament ready, and Airflow Good indicators let you monitor 
system status. These indicators do not change dynamically after you open 
the Input/Output dialog box. You must press the Refresh Status button to 
update the status indicators. 
4. The Reset Modulator sends a reset pulse to the modulator circuitry. This 
normally clears any system fault interlock logic. (If the fault condition persists, 
the fault interlock logic may cause a new fault again.) 

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A dialog box, similar to the one shown below, displays when you select Control   
Input/Output: 
3.4.5 Resample Noise 
There are two types of input signals to the receiver: the signal from a particular target 
and the signal generated by the radar system, which is referred to as noise. The 
Resample Noise command measures the receiver noise so it can be subtracted from 
subsequent measurements. During the resampling process, the internal trigger 
generator is temporarily set to a special noise rate that is usually much lower than the 
operating rate. You must verify that no returned power is present within the sampling 
interval. You may have to raise the antenna during resampling to avoid thermal noise 
from the ground or from weather targets. 
After power-up, you should issue this command at least once before the system begins 
to receive and process data. You should also occasionally issue the command to 
compensate for drift, both in the radio frequency system and in the analog-to-digital 
converter system. Finally, you must reissue the Resample Noise command when you 
change the rate or range.

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When you issue the Resample Noise command, lines similar to the ones shown below 
appear on the RDACS terminal display. 
Free run stopped 
SNOISE: Noise=1609 DiagA=0000 DaigB=0000 Imm1=42A0 Imm2=0301 
Latch=0000 
Free run started  
The following list describes each word in the listing: 
Parameter Description 
Noise 
Indicates the log of the measured noise level. 
DiagA 
Indicates the measured DC offset for the I channel. 
DaigB 
Indicates the measured DC offset for the Q channel. 
Imm1   
Imm2   
Latch 
Indicates if failures were detected during noise sampling. 
Check command to verify that everything is working 
correctly. 
If failures are detected during the noise measurement, status bits will be set in the Latch 
word.

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3.4.6 Status 
A current status listing, similar to the one shown below, displays when you select 
Control   Status. The displayed data are accessed from the Digital Signal Processor 
(the RVP7) and are described in the “Get Processor Parameters” section in the RVP7 
Digital IF Receiver User’s Manual. 
3.5 Configuration Commands 
The Configuration commands let you specify the site parameters, control the antenna, 
and edit the RDACS.ini file. 

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3.5.1  Configuration Site Parameters 
The following dialog box displays when you select Configuration     Sites: 
While most of the dialog box controls are user-definable, the fields are set during system 
configuration and should not be changed. The parameters correspond to the Site section 
of the radacs.ini file. The bottom three fields, Radar Type, Version, and Protocol, are 
read-only parameters that are set by the software. Review the site parameters, and click 
OK to dismiss the dialog box. 

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3.5.2  Antenna Control Settings 
The Antenna Control Settings dialog box controls the speed and direction of the radar 
antenna, as well as the data sample interval and offset rates. The following dialog box 
displays when you select Configuration   Antenna: 
The controls are self-explanatory. When you click OK to accept your changes, note that 
an Antenna command is reflected in the RDACS display. The commands input from the 
Antenna Control Settings dialog box correlate to the Antenna section in the rdacs.ini file, 
as shown below. 

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3.5.3  Editing the rdacs.ini File 
The Edit Rdacs.Ini dialog box displays when you select Configuration   RDACS.Ini. 
The top leftmost drop-down menu lets you select a section in the rdacs.ini file, which you 
can then view and edit, as required. The rdacs.ini file has several sections: Startup, 
Master, Site, RadPgm0, RadPgmAntennaStuck, CrossRefTables, six Mode tables, 
ModeDefault, five Level tables, Antenna, and AntennaCmds. Regardless of which 
section you choose to edit, there are three controls: Save/Apply, Save, and Exit. 
Save/Apply saves your edits and puts them into operation immediately. Save saves 
your edits, but they will not become effective until the next time you enter RDACS. Exit 
ignores your edits, asks if you want to save your edits, terminates the editing session, 
and returns you to the Radar Control dialog box. 
Section lines beginning with the # character are notes that provide important information 
about parts of the rdacs.ini file. The following paragraphs describe each section of the 
radacs.ini file. While most parameter values are not specified, important values that 
should be included in the rdacs.ini file are specified.

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Startup Section 
NumUsers= 
WatchDogType= Set to any value from 0 to 20 (0 disables 
WatchDog). When Watchdog detects that the I/O interface between 
the Digital IF Receiver and the RDACS computer is malfunctioning 
for the specified time (in seconds), the system performs a 
complete reset operation. 
TcpNoDelayUsers= 
AntennaMoveTimeout= 
#DIOPort=O 
#DIOPort=0x02a8 
DIOPort= 
Logscans= 
AutoFaultResetDelay= 
Master Section 
CfgVersion= 
# do not change the next three while rdacs runningNumModes 
NumLevels= 
NumRadPgmS 
# do not change the next three while rdacs running 
RangeResolution0= 
RangeResolution1= 
RangeResolution2=  
RangeResolution3= 
# always set to 1  
SepNoiseLevels=l  
# if 1, use defaults in rvp  
NoNoiseCmds= 

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Site Section 
The Site section of the rdacs.ini file contains many of the parameters described in 
Section 2.5.1, Configuring Site Parameters. These items, which are either set at system 
installation or are set by the software, should not be changed. 
RadPgm0 Section 
# the mode on startup 
Title= 
NumSteps= 
AntOp0= 
# this is the RdpModeNum 
Mode0=0xl 
Range0= 
Skip0= 
Duration0= 
Az0= 
E10= 
EndPt0= 

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RadPgmAntennaStuck Section 
Title=Antenna Stuck 
NumSteps= 
AntOp0= 
# this is the RdpModeNum 
Mode0=0xO 
Range0= 
Skip0= 
Duration0= 
Az0= 
E1O= 
EndPt0= 
CrossRef Tables Section 
# this section notes the mode to rdpmode xref  
# it is not used by rdacs 
mode0=rdpmode4 powerdown  
mode1 =rdpmode0 standby  
mode2=rdpmode1 long pulse  
mode3=rdpmode2 single prf  
mode4=rdpmode3 dual prf  
mode5=rdpmode5 clear air  
# level tables: 
level0=reflectivity 5-75 dBZ 
level1=speed for width,  
level2=speed for single prf +/- 20 kts  
level3=speed for dual prf +/- 99 kts  
level4=reflectivity for clear air -28 to 28 dBZ 

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Mode0 Section 
RdpModeNum=4 
Name =”PowerDown” 
Radiate= 
PowerUp= 
Mode1 Section 
RdpModeNum=0 
Name=”Standby” 
Radiate=0 
#force reset forces a modulator reset when  
# mode is entered 
ForceReset=l 

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Mode2 Section 
LogThreshold=Sets the upper limit for reflectivity values. 
Reflectivity values below this number may be discarded. This 
value is always positive. 
CalRef1= 
RdpModenUM=1 
Name=LongPulse 
Radiate= 
RAvail= 
VAvail= 
WAvail= 
PRF= 
Pulselndes= 
Unfold= 
# # 
FilterRange0= 
Filterlndex0= 
FilterRange1= 
FilterIndex1= 
FilterRange2 = 
Filterlndex2= 
FilterRange3= 
Filterlndex3= 
SampleSize=Specify from 1 to 256 pulses. 
CMS=usedefault 
Lsr=usedefault 
Dsr=usedefault 
Ccorthreshold=usedefault 
SqiThreshold=usedefault 
SigThreshold=usedefault 
ThCt1Uncorr=usedefault 
ThCt1Corr=usedefault 
ThCt1Vel=usedefault 
ThCt1Width=usedefault

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Mode3 Section 
RdpModeNum=2 
Name=”Single PRF” 
Radiate= 
Vlevel= 
RAvail= 
VAvail= 
WAvail= 
PPF= 
PulseIndex= 
Unfold= 
# # 
FllterRange0= 
Filterlndex0= 
FilterRanqe1= 
Filterlndex1= 
FilterRange2= 
Filterlndex2= 
FilterRanqe3 = 
Filterlndex3= 
SampleSize=Specify 1 to 256 pulses. 
CMS = 
Lsr= 
Dsr= 
LogThreshold= 
CcorThreshold=usedefault 
SqiThreshold=usedefault 
SigThreshold=usedefault 
CalRef1=usedefault 
ThCt1Uncorr=usedefault 
ThCt1Corr=usedefault 
ThCt1Vel=usedefault 
ThCt1Width=usedefault 

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Mode4 Section 
RdpModeNum=3 
Name=”Dual PRF” 
Radiate 
VLevel= 
RAvai1= 
VAvail= 
WAvail= 
PRF= 
PulseIndex= 
Unfold= 
# # 
FilterRange0=usedefault 
Filterlndex0=usedefault 
FilterRange1=usedefault 
FilterIndex1=usedefault 
FilterRange2=usedefault 
Filterlndex2=usedefault 
FilterRanqe3=usedefault 
Filterlndex3=usedefault 
SampleSize=usedefault 
CMS=usedefault 
Lsr=usedefault 
Dsr=usedefault 
LogThreshold= 
CcorThreshold=usedefault 
SqiThreshold=usedefault 
SigThreshold=usedefault 
CalRef1= 
ThCt1Uncorr=usedefault 
ThCt1Corr=usedefault 
ThCt1Vel=usedefault 
ThCt1Width=usedefault

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Mode5 Section 
LogThreshold= 
CalRef1= 
RdpModeNum=5 
Name=”NoRadiate” 
Radiate= 
RAvail = 
VAvail = 
WAvail= 
PRF= 
PulseIndex= 
Unfold= 
# # 
FilterRange0= 
Filterlndex0= 
FilterRange1= 
Filterlndex1= 
FilterRange2= 
Filterlndex2= 
FilterRange3= 
Filterlndex3= 
SampleSize= Specify 1 to 256 pulses. 
CMS=usedefault 
Lsr=usedefault 
Dsr=usedefault 
CcorThreshold=usedefault 
SqiThreshold=usedefault 
SigThreshold=usedefault 
ThCt1Uncorr=usedefault 
ThCt1Corr=usedefault 
ThCt1Vel=usedefault 
ThCt1Width=usedefault

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ModeDefault Section 
# O=standby l=log 2=singleprf 3=dual 4=powerdown 5=user... 
RdpModeNum= 
# mode name in fastrac and config menus 
Name=”Default” 
# set if mode should radiate 
Radiate= 
PowerUp= 
# leveln table to use for color levels 
# R, V, W=reflectivity, velocity, and width 
RLevel= 
VLevel= 
WLevel= 
# what products are available 
RAvail= 
VAvail= 
WAvail= 
# pulse width code, typ: O=2µs l=.8µs 2=user 3=user 
PulseIndex= 
# trigger frequency 
PRF= 
# maximum number of range bins 
ReqNumBins= 
# number of bins to average to product final bin 
SamplesPerBin= 
# up to 4 filters, range is in km. Index is 0 for # off, or 1 to 
7 for increasing filtering. Lower # numbered filters should have 
lower ranges 
FilterRange0= 
IndexRange0= 
FilterRange1= 
IndexRange1= 
FilterRange2= 
IndexRange2= 
FilterRange3= 
IndexRange3= 
# procmode=1 sync command mode, =2 dynamic angle sync 
# normally set to 2 
ProcMode = 
# unfold 0=none, 1=2:3, 2=3:4, and 3=4:5 
Unfold= 

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ModeDefault Section 
# number of pulses to average 
SampleSize= Specify 1 to 256 pulses. 
# 0=horiz, 1=vert, 2=alternate 
Polar= 
# clutter microsupprresion 
CMS= 
# use three lag algorithms for width, signal power, and clutter 
correction 
R2= 
# pulse end ray 
End= 
# reflectivity speckle removal 
Lsr= 
# doppler speckle removal 
Dsr= 
# rangle normalization and enables gas attenuation correction 
Rnv= 
# logslope typ=0.03 
LogSlope=003 
# logthreshold (must be >=0) 
LogThreshold= 
# clutter correction threshold 
CcorThreshold= 
# signal quality index threshold 
SqiThreshold= 
# signal power threshold 
SigThreshold= 
# calibration reflectivity 
CalRef1= 
# see SOPRM input 10 doc 

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ModeDefault Section 
TopMode=Specifies the processing mode, where 0000 Pulse Pair 
Processing; 0001 = FFT Processing; and 0010 Random Phase 
Processing. 
AGCNumPulses=Specifies the number of pulses during one AGC 
integration period. 
Window=Specifies the type of window that is applied to time 
series data where 0 Rectangle; 1=Hamming; and 2=Blackman. 
ZER=Set to 1 to zero the clutter filter‘s internal state 
variables before the delay time has elapsed. 
FilterStabDly=Specifies time delay before processing the next 
data ray. Used when dual-PRF velocity is enabled or when RVP7 has 
been reconfigured by user commands. 
# typ thctl vals: ffff = all pass, 0000 = all fail 
# AAAA=log 8888=log & ccor AOAO=log & sqi 
# weights sig: 8 sqi: 4 ccor: 2 log: 1 
ThCt1Uncorr= 
ThCt1Corr= 
ThCt1Vel= 
ThCt1Width= 
ThCt1ZdrRefl= 
# normally leave tag inverts 0  
InvTagLow= 0  
InvTagHigh= 0  
# gas atten 
GasAtten=Specifies the value for atmospheric attenuation, 
measured in dB/kin. When the water vapor is higher than this 
value, attenuation will be higher. 
# zdr cal 
ZdrCal0ff set = Specifies reflectivity depolarization ratio.  
# radar wavelength 
Wave length=Specifies the distance that the radar wave within one 
cycle.  
# use uncorrected (no range correction) ref1 
productRUseUncorr= 

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Level0 Section 
# types 0=refl 1=speed 
Type = 0 
Name=Log 
Units = dBZ 
1=5 
2=10 
3=15 
4=20 
5=25 
6=30 
7=35 
8=40 
9=45 
10=50 
11=55 
12=60 
13=65 
14=70 
15=75 
LeveI1 Section 
Type = 1 
Name=Width 
Units=knots 
1=2 
2=4 
3=6 
4=8 
5=10 
6=12 
7=14 
8=16 
9=18 
10=20 
11=24 
12=26 
13=28 
14=30 
15=32 

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Level 2 Section 
Type = 1 
Name=Single PRF Vel 
Units=knots 
1=-20 
2=-17 
3=-14 
4=-11 
5=-8 
6=-5 
7=-2 
8=0 
9=2 
10=5 
11=8 
12=11 
13=14 
14 =17 
15=20 
Level3 Section 
Type=1 
Name=Dual PRF Vel 
Units=knots 
1=-99 
2=-64 
3=-5O 
4=-36 
5=-26 
6=-20 
7=-1O 
8=0 
9=10 
10=20 
11=26 
12=36 
13=50 
14=64 
15=99 

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LeveI4 Section 
Type= 0 
Name=Clear Air 
Units =dBZ 
1=-28 
2=-24 
3=-20 
4=-16 
5=-12 
6=-8 
7=-4 
8=0 
9=4 
10=8 
11=12 
12=16 
13=20 
14=24 
15=28 

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Antenna Section 
Type=Orbit 
AzSpeed=45.0 
ElSpeed=6.0 
AzSampleStep=1.0 
AzOffset=90.0 
ElOffset=0.0 
Port=1 
ElSampleStep=0.5 
IsClockwise=1 
AntennaCmds Section 
InitCmd1=C [500d] 
#xCP vel4 acc3 boost2 prop3 inte3 diff3 zero1 
#InitCmd2=ACPOO4O/200/05/006/000/350/0[r] [500d] 
#InitCmd3=ECPOO4O/200/05/030/005/350/0[r] [500d] 
InitCmd2=ACPOO4O/100/05/030/040/350/0[r] [500d] 
InitCmd3=ECPOO2O/100/05/055/125/350/0 [r] [5OOd]  
#xCL offlset5 dowrn-ccw5 up-cw5 zero1  
InitCmd4=ACL [azoff] /00000/00000/000[r] [500d]  
InitCmd5=ECL [eloff] /35800/09500/000[r] [500d] 
AzFullCmd=G1V00000 [el] [cw] [azvel] 00000000000 [r] 
StopCmd=GOV[r] [1500d] DDD [az] [el] [r]  
#StopCmd=DDDO900001000 [r] 
#AzSectorCmd=GCE [el] 00000 [cw] [elvel] 00000000000 [r] [1500d] 
G1A [azcen] [azspn] [cw] [azvel] 00000000000 [r] 
#ElSectorCmd=GCA [az] 00000 [cw] [azvel] 00000000000 [r] [1500d] 
G1E [elcen] [elspn] [cw] [elvel] 00000000000 [r] 
AzSectorCmd=G0 [r] [l000d] G1A [azcen] [azspn] [cw] [azvel] [el] 
000000 [r] 
ElSectorCmd=G0[r] [l000d] G1E [elcen] [elspn] [cw] [elvel] [az] 
000000 [r] 

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4. RDACS Control from FasTrac 
This section provides a step-by-step procedure for accessing RDACS control while 
operating FasTrac. 
1.  Start the FasTrac program. 
2.  From the leftmost Select Panel area, select Views to open the View Main 
panel. 
3.  Under the More Settings area on the bottom of the View Main panel, select 
Data to open the View Data panel. 
Under the More Radar Settings area in the middle of the View Data panel, select 
Radar Control to open the RDACS Control panel. 

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This menu is similar to that explained in the previous sections except you have two 
additional options-Linear Intensities and Load Settings. 
1.  Linear Intensities determines which format of reflectivity data the radar uses 
when it is one of the Doppler modes. If you do not select this option, the 
radar uses Log reflectivity data. 
a.  The use of the Linear Intensities option depends on which version of the 
RDACS controller executable is installed. If you have the early file, 
HDDE.EXE, both linear reflectivity and log reflectivity are available. Since 
log reflectivity data usually provides higher quality data, do not select this 
option. If you have a later version of the RDACS controller executable, 
H250S.EXE, you have access only to linear data and you must select this 
option. 
2.  Load Settings accesses a saved RDACS configuration. You can use the 
RDACS control program to create and save up to 10 configurations (numbers 
0 through 9). Configuration 0 is loaded when you restart RDACS. You can 
set other configurations to your personal preferences and needs. For 
example, you can use a different color table to implement a clear-air mode in 
Configuration 1. Configurations 8 and 9 are temporary saves of the test 
configuration. 

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After configuring the RDACS, select Load Settings to open the Load RDACS dialog 
box. 
Specify the configuration number, and click OK to return to the View Data panel. 
OR 
Click Cancel to dismiss the dialog box and to return to the RDACS Control panel.

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5. Installing RDACS 
RDACS is normally set up when your system is delivered. The following 
instructions are provided in case your system crashes, a new version is delivered, 
or some other unusual circumstance occurs. 
There is no separate installation program. Copying the executable file to its 
destination and setting up shortcuts are manual operations. 
The rdacs directory or folder must be created before you install RvpTty. The 
steps below outline one possible way to set up the shortcuts to the program. 
Those familiar with Microsoft Windows can use their preferred technique. 
1. Copy the rdacs.exe file to your \rdacs directory. 
2.  RDACS will create the rdacs.ini file when it is needed. 
3.  Run Windows Explorer, navigate to the C. \ Windows\Start Menu\BSI folder, 
and select File   New   Shortcut to open the Create Shortcut dialog box. 
Note you may have to create the BSI folder. 
4.  Use the Browse function or key in the complete pathname for the 
\rdacs\rdacs.exe file in the Command Line text box. 

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5. Click Next, name the shortcut, and click Finish.  
6. Select Start   BSI, and verify that the new shortcut is displayed. 
7.  Right click on the desktop; then select New   Shortcut from the popup 
menu. 
8.  Use the Browse function or key in the complete pathname for the 
\rdacs\rdacs.exe file in the Command Line text box. 
9. Click Next, name the shortcut, and click Finish. A shortcut to RDACS will 
appear on the desktop. 

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6.  The radacs.ini Configuration File 
The rdacs.ini configuration file contains configuration parameters for RDACS. It is in text 
format; therefore, you can use Notepad or any equivalent text editor to view and edit the 
file contents. 
The file is organized into sections. Section headings are on a line by themselves and 
appear as a bracketed keyword, as shown in the following example: 
[Startup] 
NumUsers=10 
WatchDogType=0 
TcpNoDelayUsers=ndfastrac ndlocal wbay  
AntennaMoveTimeout=0 
#DIOPort=0 
#DIOPort=0x02a8 
DIOPort=PC17250 
LogScans=0 
AutoFaultResetDelaly=60 
[Master] 
CfgVersion=100 
#Do not change the next three while RDACS is running 
NumModes=60 
NumLevels=5 
NumRadPgms=1 
# If next are changed, RVP7 must be configured 
RangeResolution0=125.0 
RangeResolution1=125.0 
RangeResolution2+125.0 

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For example, in our example file, [Startup] is the first section and [Master] is the second 
section. Each section lists its associated variables and the current variable values 
separated by equal (j signs. (For example, WatchDogType=1 enables the WatchDog 
timer feature). Depending on the context, the value may be a real number, an integer, a 
hexadecimal integer, a Boolean expression, or an alphanumeric string. 
Note that variable names may or may not be case sensitive, depending on the context. 
To ensure correct interpretation, use the variable names are they are specified in this 
document. 
There are three ways to change the configuration file, listed in order of preference: 
 By menu commands and dialog boxes in the RDACS Config program; 
 By using the Configuration   Edit RDACS.ini menu command in the 
RDACS Config program; and 
 By editing rdacs.ini with Notepad or an equivalent text editor. 
For example, most of the variables in the Antenna section can be edited indirectly via 
the Configuration  Antenna command in RDACS Config. However, the Port variable 
in that section must be edited through Notepad. In the ensuing descriptions, each 
variable may include information on the best way to change it. If none is specified, open 
RDACS Config and use the Configuration   Edit RDACS.ini command to edit the file. 
If this document discusses a variable that is not listed in your radacs.ini file, it will have 
the default value. 
The order of section variables discussed in this document is not important. In general, 
variables are discussed in the order in which they are processed; sometimes, variable 
descriptions are logically grouped.

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The following table lists the major configuration sections: 
Section Title  Description 
Startup  System startup information 
Master  Global configuration variables 
Site  Site-specific configuration 
RadPgmN  Saved scan programs 
RadPgmAntennaStuck  Scan program used if antenna fails to 
rotate 
Antenna  Antenna configuration 
LevelN  Color/display level translate tables 
ModeN  Radar operational modes 
ModeDefault  Default settings for radar operational 
modes 
AntennaCmds  Optional section when a TSA antenna 
system is used 
Other sections may also appear. For example, the system may make a section called 
RebootRadPgm. The section and variable names are not case-sensitive; the order in 
which sections and variables appear is also not important. 
Note that sections ending in N indicate multiple sections ending in a number. In most 
cases, the first number used is 0. For example, radacs.ini includes the Mode0 and 
Mode1 sections. M and X are also be used to reference numbered sections and 
variables. 

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The subparagraphs describing each variable list the following items for each variable. 
Item Description 
Value Type  Real, Integer, Hexadecimal Integer, Boolean, and/or String. 
Range/Units  Valid ranges of values/units of values, where applicable. 
Default Value  Value used if the variable is missing from rdacs.ini 
Change Dynamically  Specifies where there are any restrictions on changing the 
variable value while RDACS is running 
RVP7User’sGuide 
Reference 
Optional reference to RVP7 program commands (typically 
this is only in the ModeN section). 
The following are the various Value Types: 
 Real-Specifies a real number, optionally with a decimal point. The number 
may be signed, depending on context. Any reasonable number of digits after 
the decimal point is allowed; however, the value may be rounded to a fixed 
number of significant digits. 
 Integer- Specifies a whole number; no decimal point is allowed. The number 
may be signed, depending on context. 
 Hexadecimal Integer- Specifies a whole number in Base 16, with a Ox prefix. 
 Boolean-Specifies a numeric 1 or 0 representing true or false, respectively. 
 String-Specifies a sequence of printable characters. Spaces may be allowed, 
depending on context. 
In some cases, more than one value type is accepted. For example, a particular 
configuration item may allow either an integer or the “none” string. 
The remainder of this document describes each section and each variable within that 
section.

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6.1 Startup Section 
This section contains configuration variables that are related to system startup and user 
options. 
TcpNoDelayUsers [Startup] 
Value Type: One or more user name strings, separated by spaces. 
Range/Units: User names that are listed in the users.txt file. 
Default Value: Empty. 
Change Dynamically? Yes. 
RDACS communicates with its users via TCP/IP, a networking protocol. When RDACS 
turns the radar data into packets of data to send to the users, TCP/IP may bundle 
several small packets of data into one larger packet. This packetizing process can 
increase networking efficiency but it can cause the data to lose its real-time look, 
especially in the case where the data is visualized as a real-time sweep, as in FasTrac. 
However, TCP/IP has an option to turn this bundling off on a connection-by-connection 
basis. When a user logs on with a name contained in the TcpNoDelayUsers list, RDACS 
instructs TCP/IP not to bundle packets for that user. The tradeoff is that more bandwidth 
is consumed on the network, so this should only be used as needed. User login names 
for applications that do not display real-time data, such as RdacCap, should not appear 
in the list. 
Changes to this variable while RDACS is running only affect new connections. 
RebootOnScsiError [Startup] 
Value Type: Boolean. 
Range/Units: 0 (disabled) or 1 (enabled). 
Default Value: 1. 
Change Dynamically? Yes. 

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If the RebootOnScsiError variable is enabled (set to 1) and if (a) a fatal error occurs on 
the SCSI to the RVP7 or if (b) the RVP7 does not seem to be responding, the RDACS 
computer restarts. This allows the system to reset the SCSI hardware, and the RVP7 will 
issue an internal reset when it detects that the SCSI interface is being initialized. 
This option can be considered a watchdog on the RDACS/RVP7 interface, and it 
normally should be enabled. If one of the described errors occurs, an entity is made in 
the RDACSLog.txt file. 
For this to be used in an unattended environment, the RDACS computer must be 
configured to start RDACS (and any other desired applications) upon system boot. Also, 
the RVP7 configuration item Respond to SCSI Reset (the RVPtty Mc command) should 
be set to YES. 
Before initiating reboot, RDACS creates the RebootRadPgm section in the rdacs.ini file. 
This section contains the currently running scan program. It also contains the Active=1 
variable, which lets RDACS know that it should run the scan program in the 
RebootRadPgm section rather than the scan program in the RadPgm0 section. 
DIOPort [Startup] 
Value Type: Integer, hexadecimal integer, or string. 
Range/Units: 0, 1, 2, 3, 4, I/O port address, or the string “PC17250’. 
Default Value: Empty. 
Change Dynamically? No, RDACS must be stopped. 

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This variable defines the type of interface to the radar transmitter and status. There are 
three types of interfaces: (1) an ISA bus I/O card, (2) a PCI bus I/O card model PCI-
7250, or (3) the RRC1 interface board integrated in the transmitter (serial interface).  
 To select (1), the ISA bus I/O card, enter the port address. For example, 
enter DIOPort=0x260. 
 To select (2), the PCI bus I/O card, use DIOPort=PCI7250. 
 To select (3), the RRC1 interface, use 1, 2, 3, or 4 to select the COM1, 
COM2, COM3, or COM4 serial port interface. 
A value of 0 can also be used. In this case, there will be no transmitter control (the 
transmitter can be operated in local mode and the status will be ignored). 
AntennaMoveTimeout [Startup] 
Value Type: Integer. 
Range/Units: Timeout; enter 0 to disable or enter number of seconds. 
Default Value: 300. 
Change Dynamically? No, RDACS must be stopped. 
If this variable is not 0, this variable specifies the timeout for taking action if antenna 
motion is not detected. Typically, the action is to stop radiating. The actual scan program 
that executes when the timeout occurs is specified in the RadPgmAntennaStuck 
section. 

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AutoFaultResetDelay [Startup] 
Value Type: Integer. 
Range/Units: Time between consecutive faults; enter 0 to disable or enter the 
number of seconds. 
Default Value: 0. 
Change Dynamically? No, RDACS must be stopped. 
This variable is used to configure automatic attempts to radiate if the radiate operation is 
shut down due to a fault. When a fault is first detected, a transmitter reset is attempted in 
five seconds. If another fault is detected, the number of seconds specified in the 
AutoFaultResetDelay variable must elapse before RDACS resends the Reset signal. 
LogScans [Startup] 
Value Type: Boolean. 
Range/Units: 0 (disabled) or 1 (enabled). 
Default Value: 0. 
Change Dynamically? Yes (use the RADACS Terminal window’s Misc    Log 
scans command). 
When this variable is set, a message displays in the log window every time the antenna 
passes through 0 degrees. The number of samples and the largest and smallest angles 
sampled are displayed. 
This can be useful to confirm correct antenna operation. Most of the time, it should be 
disabled because it quickly fills up the log file (the log file is self-maintaining but other 
useful information scrolls away faster).

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NumUsers [Startup] 
Value Type: Integer. 
Range/Units: 1 to 10 users. 
Default Value: 5. 
Change Dynamically? No, RDACS must be stopped. 
Set the number of concurrent users supported by RDACS. A typical installation could 
have the FasTrac, RadarNet Server, RdacCap, IRIS, and RDACS Config applications. 
There is no harm in just setting the maximum, 10. 
Consult Baron Services if more concurrent users are required. 
WatchDogType [Startup] 
Value Type: Integer. 
Range/Units: 0 (disabled), 1, or 2. 
Default Value: 0. 
Change Dynamically? No, RDACS must be stopped. 
This setting enables using the Watchdog timer feature available on some motherboards. 
If the variable is set to 1, the system periodically inputs a byte on port 0x443 to enable 
the Watchdog timer. It is disabled by inputting a byte on port 0x43. 
If the variable is set to 2, the Watchdog timer is periodically enabled by outputting a 
(byte) 5 on port 0x443. It is disabled by outputting a (byte) 5 on port 0x441. 
If Watchdog is enabled and RDACS hangs for some reason, the computer will be reset 
by the Watchdog hardware logic. 

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6.2 Master Section 
This section contains several global configuration variables. Two important variables are 
NumModes and NumLevels. These must match the number of ModeN and LevelN 
sections, respectively. In general, variables in this section should not be changed while 
RDACS is running. 
CfgVersion [Master] 
Value Type: Integer. 
Range/Units: 100. 
Default Value: 100. 
Change Dynamically? No, RDACS must be stopped. 
Cfg Version specifies a software version tracking number that should not be changed. 
NumModes [Master] 
Value Type: Integer. 
Range/Units: The number of mode sections defined. 
Default Value: Empty. 
Change Dynamically? No, RDACS must be stopped. 
NumModes specifies the number of mode (ModeN) sections defined in the rdacs.ini file. 
Each mode section specifies a particular operational configuration. By convention, the 
first five mode sections are Powerdown, Standby, Long Pulse, Single PRF Doppler, and 
Dual PRF Doppler. 

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NumLevels [Master] 
Value Type: Integer. 
Range/Units: The number of level tables defined. 
Default Value: Empty. 
Change Dynamically? No, RDACS must be stopped. 
NumLevels specifies the number of level conversion tables (the LeveIN sections) in the 
rdacs.ini file. These tables are used to convert engineering units (e.g., dBZ or m/s) to 
color levels. By convention, four tables are defined: Level0 through Level3. Normally, 
Level0 is for reflectivity, Level1 is for spectrum width, LeveI2 is for single PRF 
velocities, and Level3 is for dual PRF velocities. 
RangeResolutionN (N = 0, 1, 2, or 3) [Master] 
Value Type: Real. 
Range/Un its: Selected values from 50.0 to 133.3/meters. 
Default Value: 125.0. 
Change Dynamically? No, RDACS must be stopped. 
This variable specifies the range resolution for the four pulse-width configurations 
supported by RVP7. The specified value must agree with that configured by the Range 
Resolution option of the Mt<n> command of the RVP7. Valid values are 50.0, 58.3, 66.7, 
75.0, 83.3 91.7, 100.0, 108.3, 116.7, 125.0, and 133.3. 

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SepNoiseLevels [Master] 
Value Type: Boolean. 
Range/Units: 0 or 1. 
Default Value: 1. 
Change Dynamically? No, RDACS must be stopped. 
SepNoiseLevels determines if separate noise commands should be issued for each of 
the four possible pulse-width configurations. Normally, this should agree with the 
Maintain separate noise levels for each PW item of the Mp command of the RVP7. The 
recommended setting is 1. 
NoNoiseCmds [Master] 
Value Type: Boolean. 
Range/Units: 0 or 1. 
Default Value: 0. 
Change Dynamically? No, RDACS must be stopped. 
Setting this variable to 1 inhibits automatic noise sampling when a pulse-width 
configuration is selected for the first time. The recommended setting is 0. If set to 1, the 
noise variables within the RVP7 must be set in Interactive Setup mode. Note that when 
NoNoiseCmds is set to 1, noise commands are not performed, even when explicitly 
commanded. 

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6.3 Site Section 
This section is used to configure site-specific parameters, such as the radar location. 
Although these can be changed by editing the rdacs.ini file, RDACS Config supports 
changing most of these parameters via the RDACS Config menu command 
Configuration   Site. 
VersionNum [Site] 
Value Type: Integer. 
Range/Units: 102. 
Default Value: 102. 
Change Dynamically? Do not change. 
This variable specifies the software version tracking number and should not be changed. 
ProtocolNum [Site] 
Value Type: Integer. 
Range/Units: 200. 
Default Value: 200. 
Change Dynamically? Do not change. 
This variable specifies the protocol number and should not be changed. 
SiteName [Site] 
Value Type: String. 
Range/Units: Up to 31 characters. 
Default Value. Test Site. 
Change Dynamically? Yes (use the RDACS Config Configuration  Site 
command). 
SiteName can be any string that identifies the site  

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RadarName [Site] 
Value Type: String. 
Range/Units: Up to 31 characters. 
Default Value: BSI Digital Doppler. 
Change Dynamically? Yes. 
RadarName specifies the name of the radar system. Normally, it should not be changed. 
RadarType [Site] 
Value Type: Integer. 
Range/Units: 10. 
Default Value: 10. 
Change Dynamically? Do not change. 
RadarType specifies the numeric identifier of the radar type. Do not change this 
number. 
Capabilities [Site] 
Value Type: Hexadecimal integer. 
Range/Units: Bit pattern. 
Default Value: 0. 
Change Dynamically? Yes. 
Not currently used; reserved for future expansion. 

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Latitude [Site] 
Value Type: Real. 
Range/Units: Valid latitude in decimal degrees; positive for north. 
Default Value: 35.0 
Change Dynamically? Yes (use the RDACS Config Configuration   Site 
command). 
This variable specifies the latitude of the radar antenna in decimal degrees. For 
example, 35.25 in decimal degrees is equivalent to 35:15:00 in D: M: S format. 
Longitude [Site] 
Value Type: Real. 
Range/Units: Valid longitude in decimal degrees; negative for west. 
Default Value: -86.0. 
Change Dynamically? Yes (use the RDACS Config Configuration  Site 
command). 
This variable specifies the longitude of the radar antenna in decimal degrees. Note that 
western longitudes are negative. 
Altitude_AAT [Site] 
Value Type: Integer. 
Range/Units: Signed number/meters. 
Default Value: 0. 
Change Dynamically? Yes (use the RDACS Config Configuration  Site 
command). 

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Altitude_AAT specifies the antenna’s height, in meters, above the average terrain. This 
value is not used by RDACS but is passed to other programs upon request.  
Altitude_ASL [Site] 
Value Type: Integer. 
Range/Units: Signed number/meters. 
Default Value: 0. 
Change Dynamically? Yes (use the RADACS Config Configuration  Site 
command). 
Altitude_ASL specifies the antenna’s height above sea level, in meters. This value is 
not used by RDACS but is passed to other programs upon request. 
AngIe36O [Site] 
Value Type: Integer. 
Range/Units: 16384/counts. 
Default Value: 16384. 
Change Dynamically? Do not change. 
This variable specifies the number of counts in 360 degrees. This is a legacy value 
passed to other programs and should not be changed. 

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6.4 RadPgmN Section 
RDACS continually runs a scan program... (A scan program is a series of steps.) In each 
step, you can specify the radiate mode and data acquisition options, the antenna 
operation mode, and the duration of the step. When a step is completed, the next step in 
the scan program executes. When the last step is completed, RDACS loops back to the 
first step. 
Many programs consist of only one step that executes forever. However, to perform 
volume scanning or to acquire data with different data acquisition options, you must 
create a multi-step program. 
Up to ten prepared scan programs (RadPgm0 to RadPgm9) are kept in the rdacs.ini file. 
These programs are best created by using the RDACS Config Control   Load 
Program and Control    Save Program commands in RDACS. RadPgm0 is the 
program executed upon system startup. 
The RadPgmAntennaStuck section also contains a scan program. If enabled in the 
Startup section, this program is executed if the antenna quits turning. Typically, it is a 
one-step program that puts the system in Standby mode. 
If the system attempts to reboot to correct a fatal I/O error (if so enabled), the 
RebootRadPgm temporary section is created to hold the currently executing program 
so it can be restarted. It has the same variables as RadPgmN and includes the Active 
variable, which is set to 0 or 1, as needed. 
Note that the currently executing program is not necessarily contained in the rdacs.ini 
file. A program, such as FasTrac, can download its own program to be executed, and it 
will not be saved. These programs are typically one-step operations and continuously 
execute.

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To create and manage programs, use the RDACS Config Control commands. Use 
Control  Quick to create a simple one-step scan program; use Control    Program 
to create or edit a multi-step program. 
Title [RadPgmN] 
Value Type: String. 
Range/Units: Up to 39 characters. 
Default Value: “None”. 
Change Dynamically? Yes (use the RDACS Config Control commands). 
Title defines the scan program’s name. Some programs (in particular rdaccap.exe) may 
derive information about the scan program from the title. 
NumSteps [RadPgmN] 
Value Type: Integer. 
Range/Units: 1 to 30/number of steps in scan program. 
Default Value: 1. 
Change Dynamically? Yes (use RDACS Config Control commands). 
NumSteps specifies the number of steps in the scan program. For a one-step program, 
the following variables should also be present: AntOp0, Mode0, Range0, Skip0, 
Duration0, Az0, E10, and EndPt0. For a two-step program, the variables AntOp1, 
Mode1… EndPt1 should be present, and so on up to a maximum of 30 steps.  

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AntOpM [RadPgmN] 
Value Type: Integer or hexadecimal integer. 
Range/Units. 0 to 3 (with possible modifier of +16 or +32). 
Default Value: 1. 
Change Dynamically? Yes (use RDACS Config Control commands). 
This variable defines the antenna mode or operation for step M. Valid modes are: 
0 - Point or stop. 
1 - PPI (full azimuth revolution with fixed elevation). 
2 - Azimuth sector scan with fixed elevation. 
3 - RHI (elevation scan with fixed azimuth). 
If AntOpM is 1, then 16 or 32 may be added to the value to force CW or CCW rotation 
direction. If AntOpM is 2, then 32 may be added to the value to force the scan to take 
the “long path” when scanning from AzM to EndPtM. If AntOpM is 2 or 3, then 16 may 
be added to the value to force the scan to always start at either AzM or ElM. (Otherwise, 
the scan may start at EndPtM if it is closer when the step is started.) 
ModeM [RadPgmN] 
Value Type: Integer or hexadecimal integer. 
Range/Units: 0 to highest mode number. 
Default Value: 1. 
Change Dynamically? Yes (use RDACS Config Control commands). 
ModeM defines the basic radar operational mode. The value is used to find a ModeX 
section that has the RdpModeNum variable equal to the M value. 

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Note that this number does not point directly to a ModeX section. All the 
ModeX sections are searched to find a section containing a matching 
RdpModeNum value. When searching, the preferred data modifiers 
described below are ignored. 
By convention, the following values are used: Mode0 = Standby, Mode1 = Long Pulse, 
Mode2 = Single PRF Doppler, Mode3 = Dual PRF Doppler and Mode4 = PowerDown. 
Again, this convention may be altered by changing the RdpModeNum variable in the 
ModeX sections; however, it is best to keep this order for legacy programs. 
A preferred data modifier may be added to this value: this modifier can suggest, to a 
display program, what to visualize when the step S is in effect. The modifiers are 16 = 
Log Reflectivity, 32 = Linear Reflectivity, 48 = Velocity, and 64 = Width. This field is 
obsolete, and no other programs currently use this information. 
RangeM [RadPgmN] 
Value Type: Real. 
Range/Units: Total range, in kilometers. 
Default Value: 120. 
Change Dynamically? Yes (use Control menu command in RDACS Config). 
This variable specifies the radar range. In older systems with a limited number of range 
bins, this field was useful in shortening the range and, thus, increasing range resolution. 
However, with systems that have a large number of range bins, this field can be set to 
the maximum allowable range (constrained by PRF).

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SkipM [RadPgmN] 
Value Type: Real. 
Range/Units: Skip zone range, in kilometers. 
Default Value: 1.61. 
Change Dynamically? Yes (use RDACS Config Control commands). 
This variable specifies a skip zone. Data near the radar will be blanked. This can be 
used to not show strong clutter areas adjacent to the radar site. Set to 0 for no skip 
zone. 
DurationM [RadPgmN] 
Value Type: Integer or hexadecimal integer. 
Range/Units: Time in seconds or loop count. 
Default Value: 0. 
Change Dynamically? Yes (use RDACS Config Control commands). 
This variable can be used two ways: (1) as a counter or (2) as a timer. To use as a 
counter, add 32768 (0x8000) to the value. This determines how long a step will execute 
before moving to the next step of the scan program (or to return to the first step if the 
current step is the last). A value of 0 means forever and 0 is normally used in single-step 
scan programs. 
The meaning of the loop count depends on the antenna mode defined in AntOpM. If 
AntOpM is 0 (point), loop count mode should not be used. For 1 (PPI), each count is 
one-fourth of a revolution. For example, a value of 4 gives one revolution before 
proceeding to the next step. For 2 or 3 (azimuth and elevation sector scans), each 
traversal of the scan region in either direction is one count. 

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AzM [RadPgmN] 
Value Type: Real. 
Range/Units: 0 to 359.99/degrees. 
Default Value: 0.0. 
Change Dynamically? Yes (use RDACS Config Control commands). 
This variable contains the azimuth associated with the antenna mode defined in 
AntOpM. If AntOpM is 0 (point), AzM defines the azimuth at which the antenna will 
stop. For 1 (PPI), this is not used. If AntOpM is 2 (azimuth sector scan), AzM defines 
one endpoint of the sector scan - the other endpoint is defined by EndPtM. If AntOpM is 
3, AzM defines the fixed azimuth for the elevation scan. 
ElM [RadPgmN] 
Value Type: Real. 
Range/Units: -2 to 88/degrees. 
Default Value: 0.0. 
Change Dynamically? Yes (use RDACS Config Control commands). 
This variable defines the elevation associated with the antenna mode defined in 
AntOpM. If AntOpM is 0 (point), ElM defines the elevation at which the antenna will 
stop. If AntOpM is 1 or 2 (PPI or azimuth sector scan), ElM defines the fixed elevation 
for the step. If AntOpM is 3 (RHI), ElM defines one endpoint of the elevation sector scan 
- the other endpoint is set by EndPtM. 

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EndPtM [RadPgmN] 
Value Type: Real. 
Range/Units: 0 to 359.99/degrees. 
Default Value: 0.0. 
Change Dynamically? Yes (use RDACS Config Control commands). 
This variable defines the endpoint when the antenna mode is a sector scan. If AntOpM 
is 2 (azimuth sector scan), EndPtM defines the second azimuth. If AntOpM is 3 
(elevation sector scan or RHI), EndPtM defines the second elevation. It is not used for 
other AntOpM values. 
6.5 Antenna Section 
This section contains settings affecting the antenna operation. The type of antenna and 
the serial port to be used can be set in this section, as well as the antenna speed, 
sampling angle, and offset corrections. 
Other than the Type and Port variables, the recommended way to change these 
variables is to use the RDACS Config Configuration   Antenna command. 
Type [Antenna] 
Value Type: String. 
Range/Units: Either “None”, “TSA”, or “Orbit”. 
Default Value: TSA. 
Change Dynamically? No, RDACS must be stopped. 
This variable defines the type of antenna. Type selects the command set used to 
communicate with the antenna controller. If “None” is selected, no antenna control 
command will be issued. 

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Port [Antenna] 
Value Type: Integer. 
Range/Units: 0, 1, 2, 3, or 4/COM port number. 
Default Value: 2. 
Change Dynamically? No, RDACS must be stopped. 
This variable defines the COM port (serial port) used to communicate with the antenna 
controller. If 0 is selected, no antenna control command will be issued. 
AzSpeed [Antenna] 
Value Type: Real. 
Range/Units: 1 to 36/degrees/second. 
Default Value: 6.0. 
Change Dynamically? Yes (use RDACS Config Configuration   Antenna 
command). 
This variable defines the azimuth speed used in PPI and azimuth sector scan modes. 
Depending on the controller, it may or may not also affect the speed used to slew to a 
fixed azimuth. 
ElSpeed [Antenna] 
Value Type: Real. 
Range/Units: 1 to 36/degrees/second. 
Default Value: 6.0. 
Change Dynamically? Yes (use RDACS Config Configuration  Antenna 
command). 

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This variable defines the elevation speed used in RI-IT scan modes. Depending on the 
controller, it may or may not also affect the speed used to slew to a fixed elevation. 
AzSampleStep [Antenna] 
Value Type: Real. 
Range/Units: 0.1 to 2/degrees. 
Default Value. 1.0. 
Change Dynamically? Yes (use RDACS Config Configuration  Antenna 
command). 
This variable defines the angular width of a sampled radial of radar data for azimuth 
scan modes (PPI and azimuth sector scan). For example, if the value is 1.0 degree and 
the antenna mode is PPI, 360 radials will be produced for each antenna revolution. This 
variable can be set to a smaller value, but if the network link between RDACS and its 
users is slow and the antenna speed is fast, the bandwidth must be considered. Other 
factors include the number of range bins and the processing speed capabilities of 
RDACS users. 
ElSampleStep [Antenna] 
Value Type: Real. 
Range/Units: 0.1 to 2/degrees. 
Default Value: 1.0 
Change Dynamically? Yes (use RDACS Config Configuration  Antenna 
command). 
This variable defines the angular width of a sampled radial of radar data for the elevation 
scan mode (RHI). For example, if the low elevation is 0.0 degrees, the upper elevation is 
40 degrees, the ElSampleStep is 0.5 degrees, and the antenna mode is RHI, 80 radials 
will be produced for each scan cycle. When lowering this number, factors to consider 
include the network link speed between RDACS and its users, the antenna speed, the 
number of range bins, and the processing speed capabilities of RDACS users.

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AzOffset [Antenna] 
Value Type: Real. 
Range/Units: -359.9 to 359.9/degrees. 
Default Value: 0.0. 
Change Dynamically? Yes (use RDACS Config Configuration  Antenna 
command). 
This variable is used to correct for the difference between the antenna pedestal’s 
azimuth “zero” point and 0 degrees (0 degrees is north and 90 degrees is east). For 
example, if the antenna is pointing at 0 degrees, the displays indicate 10 degrees, and 
the current AzOffset is 6, AzOffset should be changed to -4. 
ElOffset [Antenna] 
Value Type: Real. 
Range/Units: -359.9 to 359.9/degrees. 
Default Value: 0.0. 
Change Dynamically? Yes (use RDACS Config Configuration  Antenna 
command). 
This variable is used to correct for the difference between the antenna pedestal’s 
elevation “zero” point and 0 degrees (0 degrees is on the horizon and 90 degrees is up). 
For example, if the antenna is pointing at 0 degrees, the displays indicate 2 degrees, 
and the current ElOffset is 0, ElOffset should be changed to -2. 

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IsClockwise [Antenna] 
Value Type: Boolean. 
Range/Units: 0 (CCW) or 1 (CW). 
Default Value: 1. 
Change Dynamically? Yes (use RDACS Config Configuration  Antenna 
command). 
This variable sets the default antenna direction when the antenna scan mode is PPI. 
6.6 LevelN Section 
This section is repeated multiple times (for example, Level0, Level1...Leveln). Each 
instance is a conversion table that translates engineering units to display, or color, 
levels. There are three types of products emanating from the RVP7: (1) R - reflectivity, 
(2) V - velocity, and (3) W - spectrum width. At least three Level table sections should be 
created, one for each product table. In practice, additional tables can be created with 
different thresholds to better match the range of values encountered in a particular 
mode. For example, if two different modes acquire velocities at different PRFs, the range 
of unambiguous velocities will be different and it may be desirable to map these into 
different display levels. 
For a given mode, which is specified in the ModeM section, the desired LevelN section 
is selected by the RLevel, VLevel, and WLevel variables. For example, if in Mode3 and 
VLevel=2, the threshold values in Level2 are used for velocities in Mode3. 
The total number of level tables is recorded in the NumLevels variable in the 
Master section. If you add or remove a section, be sure to update 
NumLevels. 

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Type [LeveIN] 
Value Type: Integer. 
Range/Units: 0 (reflectivity) or 1 (velocity). 
Default Value: 0. 
Change Dynamically? No, RDACS must be stopped. 
Type defines whether the level table is used for reflectivities or velocities. Set Type to 0 
for a reflectivity level table or set to 1 for a velocities table. Set Type to 1 for both velocity 
and width products. 
Name [LeveIN] 
Value Type: String. 
Range/Units: Up to 31 characters. 
Default Value: “None”. 
Change Dynamically? No, RDACS must be stopped. 
Name provides an arbitrary string describing the table (for example, Name=Single PRF 
Velocity). 
Units [LeveIN] 
Value Type: String. 
Range/Units: One of the strings described below. 
Default Value: dBZ or m/s, depending on Type setting. 
Change Dynamically? No, RDACS must be stopped. 

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The translate values in a level table can be in one of several different units. Units define 
the units for these values. If Type=0, then this maybe one of the following values: “dBZ”, 
“mm/hr”, or “in/hr”. If Type=1, the following values are allowed: “m/s”, “km/hr”, “mph”, or 
“knots”. The spelling and spacing of these strings are critical. For example, do not add 
spaces around the “/“in “m/s”. 
The native units used by the signal processor are dBZ and m/s. When these units are 
specified, no conversion of the threshold values in the 1, 2 ... 15 variables takes place. 
Otherwise, the threshold values are converted from the appropriate units before they are 
used. 
To convert from dBZ to rate (mm/hr), the following is used: rate = pow (10.0, (dbz/10 – 
log10 (200.0)) /1.6). 
1, 2... 15[LeveIN] 
Value Type: Real. 
Range/Units: Varies. 
Default Value: None. 
Change Dynamically? Yes. 
These variables contain the threshold values for the level table. For example, if you want 
Level1 section to represent 5 to 10 dBZ and the Units variable is “dBx “, set variable 1 
to 5 and set variable 2 to 10. 

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6.7 ModeN Section 
This section contains all of the variables used to define an operational mode except for 
antenna scan mode and range. Multiple sections (Mode0, Mode1 … ModeN) may be 
used. The total number of modes is defined by the NumModes variable in the Master 
section. 
The parameters contained in the ModeN section include radar products collected, 
radiate on/off, pulse width, PRF, and filter options. Many, but not all, parameters flow 
directly to the RVP7. 
A ModeN section is referenced from the currently executing scan program. From the 
user’s point of view, the modes are named (see the Name variable). By convention, the 
following relationships are established for the first five modes: 
 Mode0- Powerdown. 
 Mode1-Standby. 
 Mode2-Long Pulse. 
 Mode3-Single PRF Doppler. 
 Mode4-Dual PRF Doppler. 
In the first two modes, radiate is off. Mode2 is characterized by a long pulse width at a 
low PRF; therefore, no velocities are acquired. Mode3 and Mode4 use a narrow pulse 
width at a higher PRF and the full suite of products (R, V, and W) is acquired. 
Note: The total number of mode sections is recorded in the NumModes variable 
in the Master section. If you add or remove a section, be sure to update 
NumModes. 

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New mode sections cannot be created while RDACS is running. However, every setting 
can be modified in an existing mode. To add a new mode, stop RDACS and edit the 
radacs.ini file. Use Copy and Paste to copy the ModeN section most like the one you will 
be creating to a new section. Update the mode number in the new section, and update 
NumModes in the Master section. You can now change the rest of the variables, or you 
can restart RDACS and use RDACS Config to change the variables. 
If a variable is not defined in a ModeN section, the ModeDefault section is searched for 
the same variable. Further, all variables in a ModeN section can have the usedefault 
value. This also forces the system to search the ModeDefault section for the actual 
value to use. 
Name [ModeN] 
Value Type: String. 
Range/Units: Up to 39 characters. 
Default Value: “NoName”. 
Change Dynamically? Yes (connected users must reconnect to see change). 
This variable names the mode. It is not used internally except for status display. It is 
passed to user applications so that it can be presented to the operator in the list of 
available modes (e.g., see the RDACS Config Control  Quick command). 

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RdpModeNum [ModeN] 
Value Type: Integer. 
Range/Units: See text. 
Default Value: 0. 
Change Dynamically? Yes (connected users must reconnect to see change). 
When a scan program is defined, it contains a mode number that does not directly refer 
to a ModeN section. Instead, it refers to a ModeN section with a matching 
RdpModeNum variable. The reason for this extra layer of indirection is that some older 
legacy programs have the following hard coded modes: 0=Standby, 1 Long Pulse, 2 
Single PRF Doppler, 3 = Dual PRF Doppler and 4 = PowerDown. The following table 
lists the resulting RdpModeNum value when following all conventions: 
Section 
Name RdpModeNum 
Mode0 
Powerdown 4 
Mode1 
Standby 0 
Mode2 
Long Pulse  1 
Mode3 
Single PRF Doppler  2 
Mode4 
Dual PRF Doppler  3 
For example, if you are adding a new mode, Mode5, you can establish a one-to-one 
relationship between the mode section number and the RdpModeNum variable (older 
programs cannot access the new modes).

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Radiate [ModeN} 
Value Type: Boolean. 
Range/Units: 0 (no) or 1 (radiate). 
Default Value: 0. 
Change Dynamically? Yes. 
This variable defines whether the transmitter is enabled for the mode. Typically, set to 1 
unless a Powerdown or Standby mode is being defined. 
PowerUp [ModeN] 
Value Type: Boolean. 
Range/Units: 0 (powerdown) or 1 (powerup). 
Default Value: 0. 
Change Dynamically? Yes. 
This variable determines whether system power is supplied to all circuits (including 
filament voltage). If PowerUp is set to 0, some circuits are powered down (if the system 
supports Powerdown). Note that exiting a Powerdown mode may require waiting for 
filament warm-up. 
AutoReset [ModeN] 
Value Type: Boolean. 
Range/Un its: 0 (no) or 1 (yes). 
Default Value: 0. 
Change Dynamically? Yes. 
If AutoReset is set to 1 and a fault condition exists, a Reset command is issued to the 
transmitter. This is only done once, when the mode is first selected. To reiterate the 
Reset operation, see AutoFaultResetDelay in the Startup section. 

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ForceReset [ModeN] 
Value Type:  Boolean. 
Range/Units:  0 (no) or 1 (yes). 
Default Value:  0. 
Change Dynamically? Yes. 
If ForceReset is set to 1, a Reset command is issued to the transmitter when the mode 
is first selected. For repeated attempts to reset faults, see AutoFaultResetDelay in the 
Startup section. 
RLevel, VLevel, and WLevel [ModeN] 
Value Type:  Integer. 
Range/Units:  0 to Number of LeveIN sections. 
Default Value: 0. 
Change Dynamically? Yes. 
These variables select which level translate table is used for R, V, and W products 
respectively. For example, if VLevel=2, the Level2 section will be used to convert 
velocities from engineering units to display levels. 
RAvail, VAvail, and WAvail [ModeN] 
Value Type: Boolean. 
Range/Units:  0 (not available) or 1 (available). 
Default Value:  0. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: Bits 11-14 in the PROC command.

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These variables specify which of the R, V, and W products should be processed for 
delivery to user applications. Normally, for a low PRF where the unambiguous velocity is 
low, only RAvail is set. For a higher PRF, all three variables should be set to 1. 
RUseUncorr [ModeN] 
Value Type: Boolean. 
Range/Units:  0 (use corrected) or 1 (use uncorrected). 
Default Value: 0. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference:  Bits 13-14 in the PROC command. 
Normally, RVP7 delivers corrected reflectivity, for which all processing is applied. Set 
this variable to 1 to deliver uncorrected reflectivity. 
ReqNumBins [ModeN] 
Value Type: Integer. 
Range/Units: 0 - 2000. 
Default Value: 500. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: LRMSK command. 
This variable defines the approximate number of range bins that will be used for 
delivered products. The actual number used will be a few bins smaller than requested, 
depending on the skip zone range, the bin resolution, and the SamplesPerBin variable.

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SamplesPerBin [ModeN] 
Value Type: Integer. 
Range/Units: 1 to 256. 
Default Value: 1. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference:  LRMSK command. 
This variable defines the number of adjacent bins to be averaged. A value of 1 specifies 
no averaging: the number of bins requested will be the same number delivered. 
PulseIndex [ModeN] 
Value Type:  Integer. 
Range/Units: 0 to 3/index to RVP7 pulse-width tables 
Default Value:  0. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference:  SETPWF command, Bits 8-9. 
This variable selects one of four pulse-width configurations stored at the RVP7. By 
convention, a value of 0 selects long pulse and 1 selects short pulse. The remaining 
entries can be used for other pulse widths. 
PRF [ModeN] 
Value Type: Integer. 
Range/Units: 0 to several thousand/Hertz. 
Default Value: 500. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SETPWF command, Input 1.

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FilterRangeM (M = 0 to 3) 
FilterlndexM (M = 0 to 3) [ModeN] 
Value Type: Real (range) and Integer (index). 
Range/Units:  km (range) and index. 
Default Value: 0.0 and 0. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: LFILT command. 
Use these variables to configure clutter filters. Up to four filters may be defined, with 
arbitrary range. The FilterlndexM variables define which filter is selected. A value of 0 is 
off, while 1 to 7 selects progressively more rejective filters. The range of successive 
FilterRangeM variables should increase; set to 0 if the filter is not used. 
For example, to use a highly rejective filter for the first 15 km, a moderate filter for the 
next 30 km, and no filter for the remainder, the variables would be: 
FilterRange0=1 5.0 
Filterlndex0=6 
FilterRange1=45.0 
Filterlndex0=2 
FilterRange2=0 
Filterlndex2=0 
FilterRange3=0 
Filterlndex3=0 

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Unfold [ModeN] 
Value Type: Integer. 
Range/Units: 0 to 3. 
Default Value: 0. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: PROC command, Bits 8-9. 
This variable enables dual-PRF unfolding based on the set value from the following 
table: 
Unfold Meaning 
0 No unfolding 
1  Ratio of 2:3 
2  Ratio of 3:4 
3  Ratio of 4:5 
ProcMode [ModeN] 
Value Type: Integer. 
Range/Units:  1 (synchronous) or 2 (free running). 
Default Value: 2. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: PROC command, Bits 5-6. 
This variable specifies whether the synchronous mode or the free running mode should 
be used (see RVP7 User’s Guide). In almost all cases, you should set ProcMode to 2.

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SampleSize [ModeN] 
Value Type: Integer. 
Range/Units: 1-256. 
Default Value. 25. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 1. 
This variable specifies the number of pulses to be averaged. 
Rnv [ModeN] 
Value Type: Boolean. 
Range/Units: 0 (off) or 1 (on). 
Default Value: 1. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 2, Bit 0. 
This variable enables range correction of reflectivity data. It also enables intervening gas 
attenuation correction. 
Dsr [ModeN] 
Value Type: Boolean. 
Range/Units: 0 (off) or 1 (on). 
Default Value: 1. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 2, Bit 1. 
This variable enables the Doppler speckle remover. When Dsr=1, speckles in velocity 
and width data are removed.

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Lsr [ModeN] 
Value Type: Boolean. 
Range/Units: 0 (off) or 1 (on). 
Default Value: 0. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 2, Bit 2. 
This variable enables the reflectivity speckle remover. When Lsr=1, speckles in 
corrected and uncorrected reflectivity data are removed. 
End [ModeN] 
Value Type: Boolean. 
Range/Units: 0 (off) or 1 (on). 
Default Value: 1. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SQPRM command, Input 2, Bit 3. 
When End is set to 1, the ENDRAY_ output is pulsed at the end of each ray. This is not 
used by RDACS. 
R2 [ModeN] 
Value Type: Boolean. 
Range/Units: 0 (off) or 1 (on). 
Default Value: 0. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 2, Bit 7. 
When R2=1, the system uses three lag algorithms (R0, R1, and R2) for width, signal 
power, and clutter correction.

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CMS [ModeN] 
Value Type: Boolean. 
Range/Units: 0 (off) or 1 (on). 
Default Value: 0. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 2, Bit 8. 
This variable enables clutter microsupprresion prior to being averaged together in range. 
(Clutter microsupprresion is the rejection of individual range bins based on excessive 
clutter.) 
Polar [ModeN] 
Value Type: Integer. 
Range/Units: 0 to 2. 
Default Value: 0. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 2, Bits 12-13. 
This variable specifies polarization: 0 = horizontal, 1 = vertical or 2 = alternating. 
LogSlope [ModeN] 
Value Type: Real. 
Range/Units: N/A. 
Default Value: 0.03. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 3. 

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This variable specifies the multiplicative constant used to covert signal power in dB to 
units of the time-series outputs (which are not used by RDACS). Also, one-fourth of this 
value is used to generate the Log of Measured Noise Level output from RVP7’s GPARM 
command. The recommended value is 0.03. 
LogThreshold [ModeN] 
Value Type: Real. 
Range/Units: >=0/dB. 
Default Value: 0.5. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 4. 
This variable sets the LOG threshold for reflectivity values. This is only used if enabled in 
the ThCtlxxx variables. 
CcorThreshold [ModeN] 
Value Type: Real. 
Range/Units: <0/dB. 
Default Value: -25.0. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 5. 
This variable sets the clutter correction threshold. Any correction that is more negative 
than this value results in thresholding of data if enabled via the ThCtlxxx variables.

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SqiThreshold [ModeN] 
Value Type: Real. 
Range/Units: 0 to 1. 
Default Value: 0.5. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 6. 
This variable sets the signal quality index (SQl) threshold. Any SQl that is less than this 
value results in thresholding of data if it has been enabled via the ThCtlxxx variables. 
SigThreshold [ModeN] 
Value Type: Real. 
Range/Units: dB. 
Default Value: 10.0. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 7. 
When the estimate of the signal-to-noise ratio (SIG) falls below this value, data will be 
thresholded if enabled via the ThCtlxxx variables. 
CalRefI [ModeN] 
Value Type: Real. 
Range/Units: < 0. 
Default Value: -22.0. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 8.

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This variable sets the calibration reflectivity, which is referenced to 1.0 km. Changes in 
this variable result in a one-to-one change in the output reflectivity data levels. For 
example, if the reflectivity level tables specify 5 dBZ levels, a 5 dB change in this will be 
reflected as a shift of one level. 
AGCNumPulses [ModeN] 
Value Type: Integer. 
Range/Units: 1 to 255. 
Default Value: 8. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 9, Bits 0-7. 
This variable specifies the number of AGC pulses averaged. 
TopMode [ModeN] 
Value Type: Integer. 
Range/Units: 0 to 2. 
Default Value: 0. 
Change Dynamically? Yes. 
R VP7 User‘s Guide Reference: SQPRM command, Input 9, Bits 8-11. 
This variable specifies the signal processing mode used by the RVP7: 0 = pulse pair 
processing, 1 FFT processing, and 2 random phase processing. 

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FilterStabDly [ModeN] 
Value Type: Integer. 
Range/Units: Pulses. 
Default Value: 10. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 10, Bits 0-7. 
This variable specifies a delay introduced prior to processing the next radial of data 
whenever dual PRF velocity unfolding is enabled or when the RVP7 has been 
reconfigured. The delay permits clutter filter transients to settle down following PRF and 
gain changes. 
ZER [ModeN] 
Value Type: Boolean. 
Range/Units: 0 (off) or 1 (on). 
Default Value: 0. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 10, Bit 8. 
If ZER1, digital clutter filters’ internal state variables are reset to 0 prior to waiting the 
time specified in FilterStabDly. 

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Window [ModeN] 
Value Type: Integer. 
Range/Units: 0 to 2. 
Default Value: 1. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 10, Bits 9-10. 
This variable specifies the type of window that is applied to time-series data prior to 
computing power spectra via a digital Fourier transform. The values are 0 = rectangular, 
1 = Hamming, and 2 = Blackman window. 
ThCtlUncorr [ModeN] 
Value Type: Integer or hexadecimal integer. 
Range/Units: Bit pattern (16 bits). 
Default Value: 0xAAAA. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 11. 
This variable specifies threshold control for uncorrected reflectivity. The following steps 
describe how the bit patterns in the ThCtlxxx variables are used: 
1.  After a radial has been acquired, compute value x as follows: 
 Add 1to x if data passes LOG threshold. 
 Add 2 to x if data passes CCOR threshold. 
 Add 4 to x if data passes SQl threshold. 
 Add 8 to x if data passes SIG threshold. 
2.  Now x will have the value 0 to 15. It will be 0 if the data was below all thresholds; 
it will be 15 if it was above them all. 
3.  Use x to index into the bit pattern, and select one bit. If that bit is set, pass or 
keep the range data. If the bit is clear, then fail or discard the data.  

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The following table lists values of the ThCtlxxx variable for selected combinations of 
acceptance criteria: 
Value (Hex)  Criteria 
FFFF  All pass (threshold disabled) 
0000 All fail 
AAAA LOG 
8888  LOG and CCOR 
A0A0  LOG and SQI 
F0F0 SQI 
FAFA  LOG or SQI 
C0C0 CCOR and SQI 
F000  SQI and SIG 
C000  CCOR and SQI and SIG 
FFF0  SQI or SIG 
CCC0  CCOR and (SQI or SIG) 
ThCtlCorr [ModeN] 
Value Type: Integer or hexadecimal integer. 
Range/Units: Bit pattern (16 bits). 
Default Value: 0x8888. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 12. 
This variable specifies threshold control for uncorrected reflectivity. See ThCtlUncorr for 
the meaning of this value.

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ThCtIVeI [ModeN] 
Value Type: integer or hexadecimal integer. 
Range/Units: Bit pattern (16 bits). 
Default Value: 0xC0C0. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 13. 
This variable specifies the threshold control for velocity. See ThCtlUncorr for the 
meaning of this value. 
ThCtlWidth [ModeN] 
Value Type: Integer or hexadecimal integer. 
Range/Units: Bit pattern (16 bits). 
Default Value: 0xC000. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 14. 
This variable specifies threshold control for width. See ThCtlUncorr for the meaning of 
this value. 
InvTagLow 
InvTagHigh [ModeN] 
Value Type: Integer or hexadecimal integer. 
Range/Units: Bit pattern (16 bits). 
Default Value: 0. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Inputs 15 and 16. 

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This variable specifies whether selected TAG inputs to the RVP7 should be inverted. All 
current hardware requires that both these values be 0. 
GasAtten [ModeN] 
Value Type: Real. 
Range/Units: dB. 
Default Value: 0.016. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 17. 
This variable specifies the compensation for beam losses due to absorption by 
atmospheric gases. Set to 0 to disable. This value is used only if the Rnv variable is also 
set. 
ThCtIZdrRefI [ModeN] 
Value Type: Integer or hexadecimal integer. 
Range/Units: Bit pattern (16 bits). 
Default Value: 0xAAAA. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 18. 
This variable specifies the threshold control for differential reflectivity. See ThCtlUncorr 
for the meaning of this value. 

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ZdrCalOffset [ModeN] 
Value Type: Real. 
Range/Units: signed/dB. 
Default Value: 0. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 19. 
This variable specifies the offset to be added to all reflectivity polarization ratio (ZDR) 
measurements. 
Wavelength [ModeN] 
Value Type: Real. 
Range/Units: cm. 
Default Value. 5.3. 
Change Dynamically? Yes. 
RVP7 User’s Guide Reference: SOPRM command, Input 20. 
This variable specifies the radar’s wavelength, in centimeters. 

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6.8 AntennaCmds Section   
This section is only used for the TSA antenna system (the Type variable in the Antenna 
section must be set to TSA). The variables in this section hold script-like strings with 
replaceable parameters that are used to construct the command strings sent via the 
serial port to the TSA antenna. 
Firmware evolution in the ISA antenna controller has rendered the 
default values obsolete. Consult Baron Services or the ISA 
documentation before changing this section. 
In the script-like strings, replaceable parameters are denoted by a keyword in brackets. 
The keywords are listed and described in the table below. In all cases where a numeric 
quantity is created, it is 0 padded on the left to create the specified number of digits. 
Keyword  No. of Digits  Meaning
az  5  Target azimuth * 100 
azvel  4 Azimuth speed 
azvel2  2 Azimuth speed 
azv100  4  Azimuth speed * 10 
azcen  5  Target azimuth center * 100 
azspn  5  Target azimuth span * 100 
el  5  Target elevation * 100 
elvel  4 Elevation speed 
elvel2  2 Elevation speed 
elv100  4  Elevation speed * 100 
cw  1  1 if clockwise rotation; else 0 
xd  N/A Delay x milliseconds 
r  N/A  Add end of line codes 
azoff  5 Azimuth offset 
eloff  5 Elevation offset 

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InitCmdM (M = 1 to 9; TSA antenna only) [AntennaCmds] 
Value Type: String. 
Range/Units: Up to 150 characters. 
Default Value: C [r] [30d] C[r] [30d]. 
Change Dynamically? Yes. 
This command can be used to specify up to nine initialization command strings. These 
strings are sent to the antenna controller on startup and when a variable is changed in 
the Antenna section of the rdacs.ini file. 
AzFuIICmd [AntennaCmds] 
Value Type: String. 
Range/Units: Up to 150 characters. 
Default Value: G 1 V00000 [el] [cw] [azvel] 00000000000[r] [30d] G 1 V[r] [30d]. 
Change Dynamically? Yes. 
This variable is used to build the antenna controller command string to enable 
continuous rotation in azimuth. 

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StopCmd (TSA antenna only) [AntennaCmds] 
Value Type: String. 
Range/Units: Up to 150 characters. 
Default Value: G0[r] [30d] DDD [az] [el] [r] [30d]. 
Change Dynamically? Yes. 
This variable is used to build the antenna controller command string to enable pointing at 
a fixed azimuth and elevation. 
AzSectorCmd (ISA antenna only) [AntennaCmds] 
Value Type: String. 
Range/Units: Up to 150 characters. 
Default Value: GCE [el] 00000[cw] [elvel] [r] [30d] G1A [azcen] [azspn] [cw] 
[azvel] [r] [30d] G1A[r] [30d].  
Change Dynamically? Yes. 
This variable is used to build the antenna controller command string to enable azimuth 
sector scan. 
ElSectorCmd (TSA antenna only) [AntennaCmds] 
Value Type: String. 
Range/Units: Up to 150 characters. 
Default Value: GCA [az] 00000[cw] [azvel] [r] [30d] G1E [elcen] [elspn] [cw] [elvel] 
[r] [30d] G1E[r] [30d].  
Change Dynamically? Yes. 
This variable is used to build the antenna controller command string to enable elevation 
sector scan 
(RHI).