UBS Axcera 837B-5 5000-Watt UHF Translator User Manual 315945

Download:
Mirror Download [FCC.gov]
Document ID	315945
Application ID	IvxsTSeCk+NqVRhS+T638w==
Document Description	Chapter 3
Short Term Confidential	No
Permanent Confidential	No
Supercede	No
Document Type	User Manual
Display Format	Microsoft Word - pdf
Filesize	68.77kB (859649 bits)
Date Submitted	2003-04-04 00:00:00
Date Available	2003-06-17 00:00:00
Creation Date	2003-04-04 13:03:32
Producing Software	Acrobat Distiller 5.0.5 (Windows)
Document Lastmod	2003-04-04 13:03:32
Document Title	Microsoft Word - 315945.DOC
Document Creator	PScript5.dll Version 5.2
Document Author:	fcc

4-6 kW UHF Translator
Chapter 3, Installation and Setup Procedures
Chapter 3
Installation and Setup Procedures
There are special considerations that
need to be taken into account before the
837B can be installed. For example, if the
installation is completed during cool
weather, a heat-related problem may not
surface for many months, suddenly
appearing during the heat of summer.
This
section
provides
planning
information for the installation and set up
of the translator.
excessive humidity. An ideal environment
will require temperature in the range of
40° F to 70° F throughout the year,
reasonably low humidity, and a dust-free
room. It should be noted that this is
rarely if ever attainable in the real world.
However, the closer the environment is
to this design, the greater the operating
capacity of the translator.
The fans and blowers designed and built
into the translator will remove the heat
from within the trays, but additional
means are required for removing this
heat from the building. To achieve this, a
few issues need to be resolved. The first
step is to determine the amount of heat
to be removed from the translator room.
There are generally three sources of heat
that must be considered. The first and
most obvious is the heat from the
translator itself. The following example is
for a 5000 Watt Transmitter. The heat
can be determined by subtracting the
average power to the antenna (3225
watts) from the AC input power (20,000
watts). This number in watts (16,775) is
then multiplied by 3.41, which gives
57,202.75, the BTUs to be removed
every hour. 12,000 BTUs per hour equals
one ton; as a result, a 5-ton air
conditioner will cool a 5-kW transmitter.
3.1 Site Considerations
The Translator consists of three cabinet
assemblies, the Exciter Cabinet Assembly
and two Amplifier Array Assemblies. The
Exciter Cabinet Assembly requires an AC
Input of 208/240 VAC, Single Phase with
a rating of 20 Amps.
Each of the
Amplifier Array Assemblies requires an
AC Input of 208/240 VAC, three Phase
with a rating of 55 Amps or Single Phase
with a rating of 100 Amps. Check that
the site has the voltage requirement
needed.
The 837B is designed and built to provide
long life with a minimum of maintenance.
The environment in which it is placed is
important and certain precautions must
be taken. The three greatest dangers to
the translator are heat, dirt, and
moisture. Heat is usually the greatest
problem, followed by dirt, and then
moisture. Over-temperature can cause
heat-related problems such as thermal
runaway and component failure. Each
amplifier tray in the translator contains a
thermal interlock protection circuit that
will shut down that tray until the
temperature drops to an acceptable level.
The second source of heat is other
equipment in the same room. This
number is calculated in the same way as
the equation for BTUs. The third source
of heat is equally obvious but not as
simple to calculate. This is the heat
coming through the walls, roof, and
windows on a hot summer day. Unless
the underside is exposed, the floor is
usually not a problem. Determining this
number is usually best left up to a
qualified HVAC technician. There are far
too many variables to even estimate this
number without reviewing the detailed
drawings of the site that show all of the
construction details. The sum of these
A suitable environment for the translator
can enhance the overall performance and
reliability of the translator and maximize
revenues by minimizing downtime. A
properly designed facility will have an
adequate supply of cool, clean air, free of
airborne particulates of any kind, and no
837B, Rev. 0
3-1
4-6 kW UHF Translator
Chapter 3, Installation and Setup Procedures
three sources is the bulk of the heat that
must be removed. There may be other
sources of heat, such as personnel, and
all should be taken into account.
conditioned room temperature
under 80° F, the unit must be
derated, possibly by a substantial
amount.
Now that the amount of heat that must
be removed is known, the next step is to
determine how to accomplish this. The
options are air conditioning, ventilation,
or a combination of the two. Air
conditioning is always the preferred
method and is the only way to create
anything close to an ideal environment.
Ventilation will work quite well if the
ambient air temperature is below 100° F,
or about 38° C, and the humidity is kept
at a reasonable level. In addition, the air
stream must be adequately filtered to
ensure that no airborne particulates of
any kind will be carried into the
translator. The combination of air
conditioning for summer and ventilation
during the cooler months is acceptable
when the proper cooling cannot be
obtained through the use of ventilation
alone
and
using
air
conditioning
throughout the year is not feasible.
Caution: The use of air conditioning
and ventilation simultaneously is not
recommended.
This
can
cause
condensation in transmitters. For
tube-type transmitters, this can be
especially
serious
if
the
condensation forms in the tube
cavity and creates damaging arcs.
Air conditioners have an ARI
nominal cooling capacity rating. In
selecting an air conditioner, do not
assume that this number can be
equated to the requirements of
the site. Make certain that the
contractor
uses
the
actual
conditions
that
are
to
be
maintained
at
the
site
in
determining the size of the air
conditioning unit. With the desired
837B, Rev. 0
Do not have the air conditioner
blowing
directly
onto
the
translator.
Under
certain
conditions,
condensation
may
occur on, or worse in, the
translator.
3.
Do not separate the front of the
translator from the back with the
thought of air conditioning only
the front of the unit. Cooling air is
drawn in at the front of all
translators and in the front and
back of others. Any attempt to
separate the front of the translator
from the rear of the unit will
adversely affect the flow of cooling
air.
4.
Interlocking the translator with the
air conditioner is recommended to
keep the translator from operating
without the necessary cooling.
5.
The periodic cleaning of all filters
is a must.
When using ventilation alone,
following general statements apply:
The following precautions should be
observed regarding air conditioning
systems:
1.
2.
3-2
the
1.
The blower, with attendant filters,
should be on the inlet, thereby
pressurizing
the
room
and
preventing dirt from entering the
translator.
2.
The inlet and outlet vents should
be on the same side of the
building, preferably the leeward
side. As a result, the pressure
differential created by wind will be
minimized. Only the outlet vent
may be released through the roof.
3.
The inlet and outlet vents should
be
screened
with
1/8-inch
hardware cloth (preferred) or
4-6 kW UHF Translator
galvanized
(acceptable).
4.
5.
hardware
Chapter 3, Installation and Setup Procedures
cloth
Cooling air should enter the room
as low as practical but in no case
higher than four feet above the
floor. The inlet must be located
where dirt, leaves, snow, etc., will
not be carried in with the cooling
air.
The exhaust should be located as
high as possible. Some ducting is
usually required to insure the
complete flushing of heated air
with no stagnant areas.
6.
The filter area must be large
enough to insure a maximum air
velocity of 300 feet per minute
through the filter. This is not a
conservative number but a neverexceed number. In a dusty or
remote location, this number
should be reduced to 150 CFM.
7.
The inlet and outlet(s) must have
automatic dampers that close any
time the ventilation blower is off.
8.
In those cases in which translators
are regularly off for a portion of
each
day,
temperaturedifferential sensor that controls a
small heater must be installed.
This sensor will monitor inside and
outside
temperatures
simultaneously. If the inside
temperature falls to within 5° F of
the outside temperature, the
heater will come on. This will
prevent condensation when the
ventilation blower comes on and
should be used even in the
summer.
9.
The blower should have two
speeds, which are thermostatically
controlled, and be interlocked with
the translator.
11.
The blower on high speed must be
capable of moving the required
volume of air into a half inch of
water pressure at the required
elevation. The free air delivery
method must not be used.
12.
Regular maintenance of the filters,
if
used,
can
not
be
overemphasized.
13.
Tube translators should not rely
on the internal blower to vent the
cooling air at elevations above
4000 feet. For external venting,
the air vent on the cabinet top
must be increased to an 8-inch
diameter for a 1-kW transmitter
and to a 10-inch diameter for 4, 5,
6 and 10-kW transmitters. An
equivalent rectangular duct may
be used but, in all cases, the
outlet must be increased by 50%
through the outlet screen.
14.
It is recommended that a site plan
be submitted to Axcera for
comments
before
installation
begins.
In calculating the blower requirements,
filter size, and exhaust size, if the total
load is known in watts, 2000 CFM into ½
inch of water will be required for each
5000 watts. If the load is known in BTUs,
2000 CFM into ½ inch of water will be
required for each 17,000 BTUs. The inlet
filter must be a minimum of seven
square feet, larger for dusty and remote
locations, for each 5000 watts or 17,000
BTUs. The exhaust must be at least four
square feet at the exhaust screen for
each 5000 watts or 17,000 BTUs.
A controlled-air bypass system
must be installed to prevent the
temperature in the room from
falling below 40° F during
translator operation.
837B, Rev. 0
10.
The information presented in this section
is intended to serve only as a general
guide and may need to be modified for
unusually severe conditions.
3-3
4-6 kW UHF Translator
Chapter 3, Installation and Setup Procedures
A 1 kW typical layout for a combination
of air conditioning and ventilation is
shown in Figure 3-1.
As with any equipment installation, it is
always good practice to consult the
manufacturer when questions arise.
Axcera can be contacted at (724) 8738100
System interlocking and thermostat
settings should be reviewed with Axcera.
Figure 3-1. 1 kW Minimum Ventilation Configuration
3.2 Unpacking
Trays
the
Cabinets
and
Remove the Cabinets with Trays, Hybrid
Combiner and Output Coupler along with
the Installation Material that make up the
837B from the crates and boxes.
Remove the straps that hold the cabinets
to the shipping skids and slide the
cabinets from the skids. Remove the
plastic wrap and foam protection from
around the cabinets. Do not remove any
labeling or tags from any cables or
connectors; these are identification
markers that make assembly of the
translator much easier.
Note: Air conditioning and any
related heat exhaust ducts should be
in place before continuing with the
installation of the translator.
Thoroughly inspect the cabinets and all
other materials upon their arrival. Axcera
certifies that upon leaving our facility the
equipment was undamaged and in proper
working order. The shipping containers
should be inspected for obvious damage
that indicates rough handling. Check for
dents and scratches or broken switches,
meters, or connectors. Any claims
against in-transit damage should be
directed to the carrier. Inform Axcera as
to the extent of any damage as soon as
possible.
837B, Rev. 0
There are three Cabinets, (A1) the Single
UHF Exciter Assembly, (A2) the Side A 23 kW Amplifier Array Assembly and (A3)
the Side B 2-3 kW Amplifier Array
Assembly.
These Cabinets should be
arranged from left to right with you
facing the front, the A1 Single UHF
Exciter Cabinet, the A2 Side A Amplifier
3-4
4-6 kW UHF Translator
Chapter 3, Installation and Setup Procedures
Cabinet and the A3 Side B Amplifier
Cabinet. The Amplifier Arrays may have
an (Optional) External Exhaust Kit for
connection to duct work and the outside
of the building.
The UHF Amplifier Trays are labeled to
indicate where they are positioned in the
Side A or the Side B Amplifier Cabinets.
They are mounted in each Cabinet from
bottom left to top right, with A1 the
bottom left Tray and A6 the top right
Tray. The Tray labeled A1 is in the Side
A Cabinet, bottom left position. The Tray
labeled A2 is in the Side A Cabinet,
bottom right position. The Tray labeled
A3 is in the Side A Cabinet, center left
position. The Tray labeled A4 is in the
Side A Cabinet, center right position. If
present, the Tray labeled A5 is in the
Side A Cabinet, top left position.
If
present, the Tray labeled A6 is in the
Side A Cabinet, top right position.
The cabinets should be positioned with
consideration taken for adequate air
intake and exhaust to the duct work, the
opening of the rear door, access to the
Trays including sliding them out for
testing, the AC hook up and the
installation of the Output Transmission
Line. The Cabinets should be Grounded
using copper strapping material and also
should be permanently mounted to the
floor of the Site using the holes in the
bottom of the Cabinets.
The UHF Amplifier Tray labeled B1 is in
the Side B Cabinet, bottom left position.
The Tray labeled B2 is in the Side B
Cabinet, bottom right position. The Tray
labeled B3 is in the Side B Cabinet,
center left position. The Tray labeled B4
is in the Side B Cabinet, center right
position. If present, the Tray labeled B5
is in the Side B Cabinet, top left position.
If present, the Tray labeled B6 is in the
Side B Cabinet, top right position.
Remove the two L-brackets, mounted on
the front panel rails of the Single Exciter
Cabinet and Amplifier Cabinets, which
hold the Trays in place during shipment.
Inspect for any loose hardware or
connectors, tightening where needed.
Open the rear doors, the key to unlock
the door, if the door has the Optional
lock, is found in a tan envelope taped to
the door, and inspect the interior for
packing material. Carefully remove any
packing material that is found. Slowly
slide each Tray in and out to verify that
they do not rub against each other and
have no restriction to free movement.
Note: The UHF Amplifier Trays, if
removed, must be placed into the
Cabinets in the proper location
according to the labeling on each
Tray or the Gain and the Phasing will
not be maximized.
837B, Rev. 0
The trays are mounted in the cabinet
using Chassis Trak cabinet slides as
shown in Figure 3-2.
The tray slides are on the top and the
bottom of the UHF amplifier trays and on
the sides of the UHF exciter tray and the
Variable Phase/Gain Trays. Inspect the
trays for any loose hardware or
connectors, tightening as needed.
3-5
4-6 kW UHF Translator
Chapter 3, Installation and Setup Procedures
Figure 3-2. Chassis Trak Cabinet Slides
3.3 Installing the Cabinets and Trays
There are three AC Input circuits to the
Translator, one 208/240 VAC single
phase 20 Amp for the Exciter Cabinet
and two 208/240 VAC 55 Amp three
phase or 100 Amp single phase for each
of the Amplifier Array Cabinets.
Caution: Each UHF amplifier tray has
a hardline coaxial cable connected to
the rear panel. The trays will not
slide out unless this connection is
removed.
3.3.1 AC Connection to the UHF
Exciter Cabinet
To pull out the UHF amplifier trays for
test purposes, use the coaxial cable
included in the installation material kit to
make the connection from the tray to the
output cable.
In the Exciter Cabinet, the 20 Amp,
208/240 VAC Input connections are
made to the Terminal Block A8-TB1,
which is part of the AC Distribution
Assembly, Exciter Cabinet (1245-1500),
located near the center right hand side,
rear portion of Cabinet #1.
AC
connections are, Line 1 to TB1-1A, Line 2
to TB1-3A and Chassis Ground to TB12A).
It may be necessary to adjust the
position of the trays to keep them from
rubbing. This is accomplished by
loosening the cabinet slide mounting
bolts that hold the front of the slide to
the mounting frame of the cabinet and
moving the tray up or down, as needed,
to correct for the rubbing.
3.3.2 AC Connection to the Amplifier
Cabinets
Once the cabinets are in place, and the
trays are checked for rubbing, the main
AC hookup can be made.
3.3.2.1 Three Phase AC Connection
to the Amplifier Cabinets
Caution:
Before
connecting
the
208/240 VAC, make certain that all
of the circuit breakers associated
with the translator have been
switched off.
837B, Rev. 0
Connect one of the 55 Amp, 208/240
VAC Inputs to the Terminal Block
A10-TB1, which is part of the AC
Distribution
Assembly,
Amplifier
3-6
4-6 kW UHF Translator
Chapter 3, Installation and Setup Procedures
Assembly (1278-1100), located near the
center right hand side, rear portion of
Cabinet #2. Connect Line 1 to TB1-1A,
Line 2 to TB1-2A, Line 3 to TB1-3A and
Safety Ground to TB1-4A.
Line 2 to TB1-3A and Safety Ground to
TB1-4A.
Connect the other 55 Amp, 208/240 VAC
Input to the Terminal Block A10-TB1,
which is part of the AC Distribution
Assembly, Amplifier Assembly (12781100), located near the center right hand
side, rear portion of Cabinet #3.
Connect Line 1 to TB1-1A, Line 2 to TB12A, Line 3 to TB1-3A and Safety Ground
to TB1-4A.
(Refer to Figure 3.3)
3.3.3 Output Connections
The RF Output of the (A2) Amplifier
Assembly connects through (A5) a 1-5/8"
to 3-1/8" Adapter to J1 on (A4) the
Hybrid Combiner. The RF Output of the
(A3)
Amplifier
Assembly
connects
through (A6) a 1-5/8" to 3-1/8" Adapter
to J2 on (A4) the Hybrid Combiner. The
Reject Output of the combiner at J4
connects through (A12) a 1-5/8” to 31/8” Adapter to (A7) a Directional
Coupler (1016-1043) to (A8) a 2500
Watt Reject Load.
The combined RF
Output of the Combiner at J3 (3-1/8”)
connects through (A9) the Bandpass
Filter, (A10) the Output Trap Filter to
(A11) the Output Coupler Assembly
(1020-1002). The output of the coupler
at
J2
(3-1/8”)
connects
to
the
Transmission Line that is connected to
your Antenna System.
3.3.2.2 Single Phase AC Installation
to the Amplifier Cabinets
Connect one of the 100 Amp, 208/240
VAC Inputs to the Terminal Block
A10-TB1, which is part of the AC
Distribution
Assembly,
Amplifier
Assembly (1278-1200), located near the
center right hand side, rear portion of
Cabinet #2. Connect Line 1 to TB1-1A,
Line 2 to TB1-3A and Safety Ground to
TB1-4A.
Connect the other 100 Amp, 208/240
VAC Input to the Terminal Block
A10-TB1, which is part of the AC
Distribution
Assembly,
Amplifier
Assembly (1278-1200), located near the
center right hand side, rear portion of
Cabinet #3. Connect Line 1 to TB1-1A,
837B, Rev. 0
This completes the unpacking and
installation of the 837B UHF television
translator. Refer to the setup and
operation procedures that follow before
applying power to the translator.
3-7
4-6 kW UHF Translator
Chapter 3, Installation and Setup Procedures
Figure 3-3 Typical Rigid Coax Reconnection Drawing
3.4 Setup and Operation
Initially, the translator should be turned
on with the RF output at J2 of (A11)
the coupler assembly terminated into a
dummy load of 4 to 6 kW, depending
on output power of your system. If a
load is not available, check that the
output of the coupler assembly is
connected to the antenna.
Connect the on channel RF Input to the
F connector J3 for 75Ω or to the N
connector J1 for 50Ω located on (A9)
the
Remote
Interface
Assembly,
mounted on the top, rear of the UHF
Exciter Cabinet.
If the Optional
Modulator is present, connect the
baseband audio to TB1 on the A9
remoter interface assembly.
If
composite audio is used instead of
Balanced Audio, connect the Composite
Audio Input to the BNC Jack (J6).
837B, Rev. 0
Connect the Baseband Video Input to
the BNC Jack (J2) also located on (A9)
the Remote Interface Assembly.
Switch On the Main AC Circuit Breaker
located
on
the
AC
Distribution
Assembly mounted toward the rear of
the Single UHF Exciter Assembly.
Switch On the Main AC Circuit Breakers
located
on
the
AC
Distribution
Assemblies mounted toward the rear of
the Amplifier Cabinets. Switch On the
CB2-CB9 Circuit Breakers, for the
individual UHF Amplifier Trays and
Reject load fans, located on the AC
Distribution Assemblies mounted in
each Amplifier Cabinet.
Switch the Operate/Standby Switch
located on the UHF Exciter to Standby
and the Auto/Manual Switch also on the
UHF Exciter to Auto. Normal operation
of the Translator is with the switch in
3-8
4-6 kW UHF Translator
Automatic. Automatic operation of the
Exciter uses the Video Input to the
Exciter as an Operate/Standby Switch.
In Auto, if the Input Video is lost, the
Exciter
automatically
reverts
the
Translator to Standby and when the
Video Signal is restored, the Exciter will
automatically return the Translator to
Operate.
Move the Operate/Standby switch on
the UHF exciter tray to Operate.
Observe the power supply reading,
>+30 VDC(+32 VDC), on the front
panel of the UHF amplifier trays. If
present,
the
(Optional)
External
Exhaust Fan on the roof of each
Amplifier Array Cabinet will operate.
Note: If the translator does not
switch to Operate when the
Operate/Standby switch is placed
in Operate, check that an external
interlock plug, with a jumper wired
from pins 1 to 2, is connected to
jack J7 on (A9) the A/V input and
remote interface assembly.
Chapter 3, Installation and Setup Procedures
the 1-5/8" or 3-1/8" Rigid Coax Lines
or loose bolts on the connections can
cause this problem.
Observe the % Exciter Power reading of
the Meter on the Exciter, it should read
the same as written on the Test Data
Sheet for your Translator. Move the
Operate/Standby Switch, located on
the Exciter, to Standby.
The Gain and Phase controls located on
the front panels of the individual UHF
Amplifier Trays were adjusted at the
factory to attain 100% Output of the
Translator and should not need
readjusted.
The Forward Meter
readings for Side A and for Side B may
not be the same but should be the
same as, or close to the values written
on the Test Data Sheet for your
Translator.
Side A and Side B are
combined to give the correct Peak of
Sync Output, which is 100% in the
Combined Visual position.
Observe the Front Panel Meter located
on the Metering Panel with the switch
in the Combined Visual Output Power
position, it should read 100%.
If
needed, adjust the Power Adjust
screwdriver pot located on the front
panel of the UHF Exciter to attain 100%
Output on the Front Panel Meter
located on the Metering Panel with the
switch in the Combined Visual Output
Power position.
The readings on each of the individual
UHF Amplifier Trays may not be the
same. Refer to the Test Data Sheet for
your Translator and compare the final
readings from the Factory on the Test
Data Sheet with the readings on each
of the Trays after the Set Up. They
should be very close to the same. If a
reading is way off, refer to the Phasing
and Power Adjustment Procedure for
the UHF Amplifier Trays in the Detailed
Alignment Procedure before trying to
adjust.
As you are checking the output Power
Level, check the Meter Readings on the
Metering Panel in the % Reflected
Power Position for the Side A and also
the Side B Amplifier Assemblies and the
Combined position for the Translator.
If the % Reflected Power for any of the
readings is very high, above 20%, a
problem with the Output Coaxial Lines
in the problem Side Amplifier Assembly
or in the Output Lines for the System is
present and needs to be checked and
corrected. A center bullet missing from
If a dummy load is connected to the
Translator, switch the Translator to
Standby and switch Off the Main AC
Circuit Breakers found on the AC
Distribution Panels in each Cabinet.
Remove the dummy load and make all
connections needed to connect the
Translator to the Antenna for your
System. Switch the Main AC Circuit
Breakers On and the Operate/Standby
Switch to Operate. Adjust the Exciter
Power Adjust pot to attain 100%
Combined Output.
837B, Rev. 0
3-9
4-6 kW UHF Translator
If the Translator is already connected
to the Antenna, check that the
Combined Output is 100%. If needed,
adjust the Power Adjust Pot located on
the UHF Exciter for 100% in the
Combined Output position.
This completes the translator setup and
operation procedures for the 837B UHF
837B, Rev. 0
Chapter 3, Installation and Setup Procedures
solid state translator. The translator
can now be operated normally.
If a problem occurred during the setup
and operation procedures, refer to
Chapter 5, Detailed Alignment
Procedures, of this manual for more
information.
3-10

---

Source Exif Data:

File Type                       : PDF
File Type Extension             : pdf
MIME Type                       : application/pdf
PDF Version                     : 1.3
Linearized                      : Yes
Create Date                     : 2003:04:04 13:03:32-08:00
Modify Date                     : 2003:04:04 13:03:32-08:00
Page Count                      : 10
Creation Date                   : 2003:04:04 21:03:32Z
Mod Date                        : 2003:04:04 21:03:32Z
Producer                        : Acrobat Distiller 5.0.5 (Windows)
Author                          : fcc
Metadata Date                   : 2003:04:04 21:03:32Z
Creator                         : fcc
Title                           : Microsoft Word - 315945.DOC

EXIF Metadata provided by EXIF.tools