ISC Technologies ISC-T5540 Non Broadcast Transmitter User Manual 9T97A250 Manual Rev B

ISC Technologies Inc Non Broadcast Transmitter 9T97A250 Manual Rev B

Contents

  • 1. Users Manual
  • 2. User's Manual

Users Manual

Copyright 2005 ISC Technologies 9T97A250 450-MHz Power Amplifier User Manual 9110.00118 REVB
Copyright 2005 ISC Technologies Table of Contents 1 GENERAL 2 RESERVED 3 DESCRIPTION 3.1 Front Panel Display and Alarms 3.2 Features 3.3 Physical Description 4 P. A. CIRCUIT AND LOGIC CIRCUIT DESCRIPTIONS... 4.1 Power Amplifier Circuit Description 4.2 Logic Circuit Description 5 INSTALLATION 5.1 Overview 5.2 Cabinet Installation 5.3 Operating and Servicing Hazards 5.4 Checks and Adjustments 5.5 Equipment Needed 6 ADJUSTMENTS 6.1 Power Amplifier Alignment and Tuning 6.2 Logic Alignment
Copyright 2005 ISC Technologies 1 GENERAL This manual is intended for use by experienced technicians familiar with RF communication systems. It contains all the necessary information required to align, install, interface, and operate the 9T97A250 UHF Power Amplifier. Any questions regarding the equipment or this manual should be directed to Customer Ser-vice. ISC Technologies One Glenayre Way Ste. 2 Quincy, IL 62301 Phone: (217) 221-0985 Fax: (217) 221-9775 2. Reserved 3 DESCRIPTION The 9T97A250 UHF power amplifier is designed for FM operation in the 406 to 470 MHz band. The RF power output is continuously adjustable from 50 watts to 250 watts when driven by a 4-watt source. The RF input and output connectors are the type N panel mount (UG-58 AN) and are mounted on the rear of the power amplifier. Input dc power is fed to the power amplifier through a two-terminal barrier strip on the rear of the power amplifier. A 15-pin D-connector (for monitoring the power amplifier’s operating condition using its associated test set) is mounted near the barrier strip. Forced air circulation is through the front panel, using an internally controlled dc fan. The power amplifier is self-protected against overheating and mismatched load conditions (including open and short circuit conditions). DANGER ! RF power transistors and RF termination resistors contain beryllium oxide. Beryllium oxide fumes ARE TOXIC! No treatment should be attempted without proper precautions. Disposal via public waste is strictly forbidden! 3.1 Front Panel Display and Alarms Power Output Bar-Graph Indicates relative output power in ten levels (red). RF Input LED Indicates RF input power is applied (green). High VSWR LED Indicates an alarm due to high reflection at the output (red). High Temperature LED Indicates an alarm due to over heating (red). Power On LED Indicates that the dc supply is applied to the power amplifier (green).
Copyright 2005 ISC Technologies 3.2 Features The 9T97A250 power amplifier has the features listed below. • Adjustable power output. • Continuous operation. • Mounts on a 19-inch standard EIA rack panel. • Self-resetting protection circuitry. • Modular construction. • Status and power output display. • Easy access to amplifiers and protection circuitry for adjustment. • Independent fusing of each final module and the driver with open fuse indicator on the rear panel. 3.3 Physical Description The 9T97A250 UHF power amplifier is rack panel mountable (19-inch). Front and rear covers are removable to gain access to all controls without removing the 9T97A250 from the rack. The front panel display consists of a red LED bar-graph display showing output power. Two red and two green status LEDs are also located on the front panel. The rear panel consists of an RF input connector, an RF output connector, a DB-15 connector, and a two-terminal barrier strip for dc power connections. 4 P. A. CIRCUIT AND LOGIC CIRCUIT DESCRIPTIONS 4.1 Power Amplifier Circuit Description 4.1.1 General The RF input, which is sampled by the alarm logic, is amplified by the RF power driver. The driver’s net RF power output is varied by adjusting the dc voltage supply. The driver’s power output is split into four parts which become the input power to each final. Each final amplifies this input power and the output from the finals are combined and filtered. The alarm logic samples both the output forward power and reflected power. 4.1.2 Driver The driver module has two functions. Its primary function is to provide a variable power input to the final power amplifier module, so that the net output power of the final amplifier can be adjusted. The second function is to provide a sampling point for the alarm logic at the input power point to the power amplifier. The driver uses a MOS-FET transistor (Q1) with two dies in one package, operated in push-pull configuration. R2 and R3 provide zero bias at the gates of Q1 for class C operation. T1 and T2 are 1:1 balun transformers. Capacitor C4 at the input of the driver is adjusted to fine tune the input match to 50 ohms, thereby minimizing input standing wave reflection. Capacitor C16 couples a small amount of input power through diodes D1 and D2. This dc voltage, which is proportional to the RF input, is fed to the alarm logic. The rectified RF at the anode of D1 is smoothed by capacitor C17 and loaded by resistor R1. The main part of the RF input goes through T1, C2, C3, Z1 and Z2 and capacitors C1, C4 and C5 match the transistor’s input impedance across the frequency band. Power (3-5 Vdc) is fed via a “fast-on” tab to the drains of transistor Q1. Matching of the transistor’s output impedance across the frequency band is provided by Z3, Z4, C6. C7 and C10. Capacitors C5 and C9 are for dc blocking.
Copyright 2005 ISC Technologies 4.1.3 Splitter The splitter consists of three splitters to provide a four-way divider. Each splitter is a ninety degree hybrid and a 50-ohm load. A ninety degree hybrid is a length of wire line in this case. The length is determined by the frequency band of the power amplifier. The wireline is a form of semi-rigid 50-ohm coax that has two center conductors insulated from each other. Within the useable bandwidth, each hybrid splits the RF power into approximately two equal parts that differ in phase by about ninety degrees. As the split and phase differ, some power is dissipated in the load resistors terminating the fourth port of the hybrids. When power is reflected from any other port, the bulk of this reflected power (nominally half) is dissipated in the load. The remaining power is split equally between the other two ports. The process of splitting and combining is very phase sensitive. Incorrect phasing will result in power wastage, increased heat through power dissipation, reduced MTBFs. and reduced output power. As a result, all cables between the splitter and the finals, and the combiner must be exactly the same length. The necessary phase adjustments for manufacturing tol-erances are provided by the tuning capacitors in the finals. 4.1.4 Final All final modules are identical, only one module is described. The final module amplifies the output of the splitter to about 65 watts and feeds this to the combiner. The final is a common emitter class C amplifier. The transistor’s (Q1) input impedance is matched to 50 ohms across the frequency bandwidth using micro striplines Z2, and Z3, with capacitors C2, C3, C17, C5, and C6. Power (28 Vdc) is fed via a faston tab to the collector of transistor Q1 through a dc-coupling network. Matching of the transistor’s (Q1) output is provided by Z4, Z3, C8, C9, C10, and C18. In addition, C12 fine tunes the output. 4.1.5 Combiner Like the splitter, the combiner consists of three ninety-degree combiners providing a four-way combiner. Each combiner is a ninety degree hybrids and a 50-ohm load. A ninety de-gree hybrid is a length of wireline in this case. The length is determined by the frequency band of the power amplifier. The wireline is a form of semi-rigid 50-ohm coax that has two center conductors insulated from each other. Within the useable bandwidth, each hybrid combines the approximately equal RF feeds (each feed differs in phase by about ninety degrees), into one. As the phase differs, some power is dissipated in the load resistor terminating the fourth port of the hybrid. The resis-tive load’s most important function in the combiner is to dissipate the bulk of any reflected power (nominally half). The remainder of the reflected power is split equally between the other two ports (typically). 4.1.6 Low Pass Filter and Directional Coupler The low pass filter attenuates the harmonics generated by the power amplifier. The direc-tional coupler samples, and detects output power and reflected power. These signals are then passed to the alarm logic. The output of the combiner is fed through the low pass filter (C1, C2, C3, C4, L1, L2, and L3) and the directional coupler to the power amplifier’s output connector. The directional coupler consists of three micro striplines Z1, Z2, and Z3 with loads and detector circuits at both coupled ports. The directional coupler provides about -33 dB of coupling at the center frequency. Schottkey diodes (D1 and D2) are used for de-tection of forward and reflected RF power.
Copyright 2005 ISC Technologies 4.1.7 DC Distribution Board The distribution board supplies 28 Vdc to each final module and 3 to 25 Vdc to the driver module. Each final and the driver is fused through 10 A fuses F2 to FS, current monitoring resistors R1 to R4 and EMI filters for short circuit protection and shielding purposes. For added protection, the current to each final may be monitored. Capacitors and the low pass EM! filters are used on each of these lines to prevent low and high frequency noise from penetrating or leaving the shielded amplifier housing. Fuse Fl is for short circuit protection on the logic board and driver module. The adjustable dc supply to the driver module and the direct current signals representing the RF input, RF output, and reflected RF are also filtered on this board. The power am-plifier’s dc input terminals TB2 and test set connector JI are mounted on this board. Con-nections to the logic board are also made through P2. 4.2 Logic Circuit Description 4.2.1 General The logic board is a control board mounted behind the front panel of the 97 series RF power amplifiers. It gives visual indication of the RF power amplifier’s operating condition, and indication of the variable power supply to the driver of the RF power amplifier. The logic board also contains the RF detection circuit, power meter, temperature controller, 2 minute timer, fan driver, and optional fixed bias supply. The logic board has three connectors; a 1 x 2-pin connector for the dc fan power, a 6-pin connector for the regulator, and a 2 x 8-pin connector for the power control signals. 4.2.2 Power Supplies 4.2.2.1 Introduction The three power supplies internal to the PA are: the adjustable driver supply with the ability to switch between high and low power, the 8 Vdc regulator, and the fixed bias power supply. 4.2.2.2 Adjustable Driver Supply An adjustable voltage (produced by regulator U5) buffered by a transistor external to the logic board produces a stable, high power variable power supply even under a dynamic load. The output is adjusted by resistors R52 and R53, and can be switched to high power (de-fault), low power (high at P10-10 to switch Q6, or a high at P10-6 when JR27 is installed), or power off (high at P10-6 to switch Q3 when JR26 is installed). When Q3 is turned ON, the adjustment pin of U5 is shorted to ground. This will cause the output of U5 to drop to a minimum voltage (about 0.9 Vdc at P10-2, 3). Filtering capacitors C33, C30, C52, C51, C54, C53, C55, C56, and C57 are used at the input and output of U5 and the external tran-sistor, in order to reduce the ripple voltage which may be caused by the ac line voltage, dc fan, or possibly the RF signal. Resistors R55 and R57 provide minimum load current for U5 and the external transistor while D22 and D24 protect U5 from potential reverse bias conditions. 4.2.2.3 Eight Volt Supply The 8 Vdc regulation and power to the logic circuit is handled by U6 which is protected by diode D23.
Copyright 2005 ISC Technologies 4.2.2.4 Fix Bias Supply At P10-4, a 0.64 and 0.05 Vdc bias power supply is produced by QA1B, QA1D, QA1E, and Q5. This bias voltage is used to bias some of the power amplifier’s driver transistors. 4.2.3 RF Power Detection The rectified RF signals (RF in, forward RF output, and reflected RF output) provided by the power amplifier’s directional coupler and input detector are processed to indicate the power amplifier’s status. The RF levels are buffered and compared by U3 and U7. See Section 6.2.2, Low and High Power Adjust, for setting the comparator’s reference voltage level. The forward RF output signal is fed to US. The linear bar graph gives an approximation of the power amplifier’s output RF power. The indication range of bar graph LED’s Dl1 to D20 is from 10% to 100% of the power amplifier’s RF output. Resistor R48 is used to adjust the bar graph. One of ten jumpers (JR 12 to JR2I) is used to set the relative low forward RF output; a logic high at U2’ s pin 5 indicates a relative low RF level detected. The second jumper (from JR2 to JRI 1) is select-ed for turning on the fan whenever output power is detected above a threshold level (about 20%). 4.2.4 Status Indication and Alarm The power on LED D7, and RF IN LED D8, are green. LED D8 indicates the input status of the power amplifier. LED D8 is turned on whenever 50% of rated exciter power is detected. The level of triggering D8 is adjusted by R50. The high reflection output LED D9, and overheat LED D10, are red. When these LED’s are illuminated, this indicates a problem in the power amplifier. LED D9 is latched by Q1 where the reflected level is detected above a certain level (30% of rated power amplifier power) for approximately 10 ms. LED D9 is disabled only by resetting the latch (U1 and the NOR RS flip flop). It is reset on the application or removal of PTT (or by a transition from low to high or high to low power) if the alarm condition has been corrected. The temperature sensor, mounted on the heatsink, will switch on Q2 and LED D10 when it detects the ambient temperature of the heat sink is above the rated temperature level (set by R14 and R28 or R51). There is about 10oC hysteresis built into the temperature sensor circuitry to ensure the power amplifier is cooled down before the next transmission. The overheat signal sent by the temperature sensor is latched by U1, and sends an alarm signal to the system through P10-11. The overheat alarm will only be reset when the heat sink is cool enough for the power amplifier’s next transmission. The alarm signal is fed to driver regulator switch Q3, and it will disable the power amplifier (JR26 installed) or switch the power amplifier to low power (JR27 installed) as long as the alarm condition is present. On the other hand, it is desirable to disable the alarm signal, and enable the power amplifier when a new antenna system is set up at a site. This can be achieved by removing JR26 or JR27 (which ever is installed). Note Remember to replace JR26 or JR27 (whichever was installed) after theantenna system is set up. The power amplifier may be shutdown remotely if desired, by supplying 5 Vdc to pin 14 on connector DB15.
Copyright 2005 ISC Technologies 4.2.5 Timer and Fan Driver The oscillator and programmable timer (U10), has its oscillation frequency determined by R46, R47, and C48 (fosc = 1/(2.3 R47 C48) when R46 = 2*R47). This driver operates as a one shot 2 minute timer, and its counter is reset when it is powered up or pin 6 of U10 is set. The counter will count up to 2 minutes of logic low at pin 6 of U10, then reset the Q output to a logic low. There are four possible inputs that reset the 2 minute timer; power on, high RF input level, high RF output level, and overheat sensor. Note The fan may be jumpered on by installing JR25. 4.2.6 Overheat Sensor and Reference Temperature Level If the ambient temperature detected by the temperature sensor is higher than the reference temperature (set by R14, and R28, or R51), the temperature sensor turns on switch Q2. Switch Q2 then turns on overheat LED D10, and sets the alarm. The temperature sensor has hysteresis determined by R29 and R32. 5 INSTALLATION 5.1 Overview The transmitter location should be chosen to protect the equipment from dust and extreme environmental conditions. The transmitter can either be installed in any standard EIA 19-inch rack or ordered with one of two optional 19-inch rack cabinets. An optional cabinet can be ordered for indoor transmitter locations. Before installing the cabinet, open the transmitter’s cabinet door and examine all equipment closely to ensure that all packing was removed and that all required printed circuit boards, other plug-in units, bolt-on equipment and electrical connections are secure. Replace any panels removed, and close the cabinet door after your inspection. Cabinet Installation DANGER The optional cabinet, with one transmitter, has an approximate mass (weight) of 76 kg (167 lbs.). Ensure that the proper equipment and the required number of persons are available when lifting or moving your cabinet-installed transmitter to prevent injury to personnel or equipment.
Copyright 2005 ISC Technologies Indoor Cabinets This upright style cabinet has provisions in the base for bolting it down to a concrete floor. All cabinets have an ac power outlet strip with six grounded outlets and a 4.5 meter (15 foot) CSA (UL) approved, three-wire line cord installed in the cabinet’s base. Remove the knockouts that best fit your installation needs when routing the ac power cord, antenna cable, and other wiring. Caution DOC and FCC Rules and Regulations require that the transmitter be installed so that all controls are protected from adjustment by unauthorized personnel. Cabinet doors must be kept locked unless the transmitter area is secure. Transmitter Rack Mounting When the Power Amplifier is ordered without a cabinet, it is supplied with rack mounting hardware and can be installed in any standard EIA 19-inch rack. However, certain guide-lines should be followed when installing the transmitter. The Power Amplifier location should provide enough unobstructed space (at least 30cm [12 inches]) immediately to the rear of the large finned heat sink and fan located on the rear of the PA chassis. This space is necessary for proper cooling of the amplifier power elements. When the Power Amplifier is installed in a cabinet, airflow through the cabinet should not be restricted, and the cabinet should have ample louver openings for airflow at both top and bottom. 5.3 Operating and Servicing Hazards Voltages Operating voltages ranging from a few volts to 120 or 240 volts ac are present in this equipment. Care has been taken in the design of the equipment to insure personnel safety. Terminals where ac line voltages are present are enclosed by covers that require tools for removal. Do not remove these covers or service the equipment with ac power applied to the equipment. Human Exposure to Radio Frequency Energy In August 1996 the Federal Communications Commission (FCC) of the United States with its action in Report and Order FCC 96-326 adopted an updated safety standard for human exposure to radio frequency (RF) electromagnetic energy emitted by FCC regulated transmitters. Those guidelines are consistent with the safety standard previously set by both U.S. and international standards bodies. The design of this product complies with the FCC guidelines and these international standards. This equipment is intended for use only in a permanent professionally installed licensed site. Licensing of that site may require that an Environmental Assessment be performed based upon human access, antenna type, antenna mounting height, ERP, operating frequency, duty factor, and any co-located transmitters that contribute to the overall Radio Frequency energy exposure level. Compliance is ultimately the responsibility of the site licensee and a determination of compliance can only be made by evaluating the complex factors of the specific site.
Copyright 2005 ISC Technologies 5.4 Checks and Adjustments Your transmitter was completely checked out and performing within operating specifications when it left the factory. Since signal levels, control voltages, and possible ac line voltage may vary from those used in factory testing, the following system checks and adjustments should be made when the equipment is initially placed into service. 5.5 Equipment Needed The following tools and equipment will be required to install the 9T97A250 RF power am-plifier. • ISC Technologies UHF 4-watt amplifier and DSP exciter. • Power supply: 28 Vdc 24 A minimum. • Directional wattmeter, 50 ohms, 5-watts full scale, 5% accuracy. • Directional wattrneter, 50 ohms, 250-watts full scale, 5% accuracy. • 50-ohm termination 250 W. • DC voltmeter: 30 Vdc minimum. • DC ammeter: 25 A full scale, 2.5% accuracy. • Rack mount hardware. • Cables with appropriate connectors. • One jumper: 0.1 spacing, (270-0501). 5.6 Procedure 1. Install the exciter shelf, power supply, and power amplifier into the rack, but do not interconnect. 2. Connect the voltmeter to the power supply. Check that polarity is correct. Check that the leads are not shorted out. 3. Switch ON the power supply and check that the voltage is 28 Vdc within 0.1 Vdc. Adjust the power supply if necessary. 4. Switch OFF power supply. 5. Disconnect voltmeter leads after the power supply has discharged. 6. Connect the power supply to the barrier strip on the rear of the power amplifier. Check that polarity is correct. 7. Remove placard and turn ON power supply. Check that the green power light on the front panel of the power amplifier is illuminated, and the fan is operating. 8. If the LED is not on, turn OFF the power supply and check fuses and polarity of the cables. If the LED still does not illuminate, or the fan does not start. contact ISC Technologies Customer Service before continuing. 9. Switch OFF the power supply and connect the exciter output through the 5-watt F.S. directional wattmeter to the 5-watt R.F. load. 10. Switch ON the power supply, and key the exciter. Check that about 4.0 watts +/-0.2 watts is produced when the exciter is keyed. Switch OFF the exciter and disconnect the 5-watt R.F. load.
Copyright 2005 ISC Technologies 11. Connect the 50-ohm cable from the power amplifier’s output through the 250-watt F.S. directional wattmeter to the 250-watt R.F. load. 12. Connect the exciter’s output from the 5-watt F.S. directional wattmeter to the power amplifier’s input. 13. Switch ON the power supply and key the exciter momentarily. Check that the power amplifier’s power output is about 250 watts. 14. If this is not the case, follow the power amplifier alignment and logic circuit alignment procedures in Section 6 before continuing with this installation. 15. Key the exciter momentarily and note the reflected power between the exciter and the power amplifier. If this is greater than 0.2 watt, contact ISC Technologies Customer Service before continuing. 16. Switch OFF the power and disconnect the 5-watt F.S. directional wattmeter between the exciter and power amplifier. Connect the exciter directly to the power amplifier. 17. Switch ON the power supply and key the exciter. Check that the power amplifier’s output power is acceptable. 18. Switch OFF the power supply and disconnect the 250-watt R.F. load. Remove the front panel of the power amplifier and connect the power amplifier’s output to the antenna system through the 250-watt F.S. directional waif meter. 19. Switch ON the power supply and key the exciter momentarily. Note the reflected power from the antenna system. 20. If the power amplifier shuts down, remove JR26 or JR27 (whichever is installed) on the logic board and note the reflected power from the antenna system. DANGER If the reflected power is greater than 8% of the required output power, the power amplifier should not be used in this application subject to a void warranty. Contact ISC Technologies Customer Service. 21. If the reflected power is less than 8%, and the power amplifier shuts down with JR26/JR27 installed, switch OFF the power supply and contact ISC Technologies Customer Service. 22. Replace JR26 or JR27 if removed previously. (The power amplifier did not shut down, and reflected power is less than 8%). 23. Disconnect the 250-watt F.S. directional wattmeter, and replace the front cover. The power amplifier is ready for use.
Copyright 2005 ISC Technologies 6 ADJUSTMENTS 6.1 Power Amplifier Alignment and Tuning 6.1.1 Why You Need to Tune The 9T97A250 RF power amplifier is factory adjusted at the desired frequency. If the fre-quency of operation has to be changed by more than 2 MHz away from the previous fre-quency, then the following adjustments should be made. This is to ensure the power am-plifier’s optimum performance and increase the life of the RF power transistors. 6.1.2 Equipment Needed The following tools and equipment will be required to properly align the 9T97A250 RF power amplifier. • Directional wattmeter, 50 ohms, 5-watts full scale, 5% accuracy. • Directional watimeter, 50 ohms, 250-watts full scale, 5% accuracy. • 50-ohm termination 250 W. • Tuning tool, slot, insulated. • DC ammeter: 25 A full scale, 2.5% accuracy. • Cables with appropriate connectors. • Test set: M-97. 6.1.3 Exciter Check 1. Set up the exciter and test equipment as shown in Figure 6-1. 2. Switch ON the power supply and key the exciter. Check that the output power is 4.0 watts +/- 0.2 watts. 3. If the power output is not within this range, switch OFF the power supply and replace the exciter. 6.1.4 Power Amplifier Adjustments 1. Switch ON the power supply and key the exciter. 2. Adjust C12 on the first final for maximum power. 3. Record the current reading of this final from the M-97 test set. 4. Increase the capacitance of C12 on the first final until the power drops by 2 watts from the maximum power peak. 5. Check that the current reading has decreased on the M-97 test set. 6. Repeat steps 2 to 6 for the second final. 7. Repeat steps 2 to 6 for the third final. 8. Repeat steps 2 to 6 for the fourth final.
Copyright 2005 ISC Technologies 9. Adjust C4 on the driver module for minimum reflected power from the power amplifier back to the exciter. 10. Adjust C2 or C3 (depending upon the band) on each final power amplifier module for maximum output power. 11. Adjust R52 (HIGH PWR ADJ) on the logic board for 250 watts of output power. 12. Repeat steps 3 to 11 until tuning does not effect the output power of the power ampli-fier. 13. Check that the total dc current draw for the power amplifier is less than 21 A on the dc ammeter, and the M-97 test set current reading for the final modules is less than 20. 14. Adjust R52 (HIGH PWR ADJ ) for the desired output power level. 15. Switch OFF the power supply, disassemble the test equipment, and connect the exciter and power amplifier in its normal configuration. 6.2 Logic Alignment 6.2.1 Equipment The following tools and equipment will be required to properly align the 9T97A250 RF power amplifier. • Directional wattmeter, 50 ohms, 250 watts full scale, 5% accuracy. • Directional wattmeter, 50 ohms, 5 watts full scale, 5% accuracy. • 50-ohm termination 250 W. • 10 Vdc minimum voltmeter. • Two jumpers, 0.1 spacing (GL 270-0501). • DC ammeter: 25 A full scale, 2.5% accuracy. • 3 dB attenuator, 5 watt minimum. • Test set: M-97. 6.2.2 Low and High Power Adjust 1. Remove JR26 or JR27 (which ever is installed) to inhibit power auto shutdown. 2. Switch the M-97 test set to low, power, or connect pin 12 to pin 15 of the DB15 connector, or install JR29. 3. Switch ON the power and key the exciter. 4. Adjust R53 (LOW PWR ADJ) on the logic board until the desired LOW power output is obtained. 5. If the LOW power setting is not required, turn R53 fully counter clockwise. Note Rotating R53 (LOW PWR ADJ) clockwise, increases output power. 6. Switch the M-97 test set to “HIGH” power, or disconnect pin 12 from pin 15 of the DB15 connector, or remove JR29 if installed. Turn R52 (HIGH PWR ADJ) on the logic board until the power amplifier’s forward output power is about 225 watts.
Copyright 2005 ISC Technologies 7. Turn R48 (BAR GRAPH ADJ) on the logic board so that 100% LED D11 of the bar graph,just lights up. 8. Turn R52 (HIGH PWR ADJ) on the logic board until the desired HIGH power output is obtained, 9. Switch OFF the power and install a 3 dB attenuator between the exciter and the power amplifier. Switch ON the power again and key the exciter. 10. Turn R50 (RF IN LEVEL SET) on the logic board until the RF IN LED D8, just lights up. 11. Install JR28 and verify that LED D8 still turns on. Turn R50 if necessary, until D8 (RF IN LED) just turns on, then remove JR28. 12. Switch OFF the power, and remove the 3 dB attenuator installed between the exciter and the power amplifier. 13. Install either JR26 or JR27 to enable the power auto shutdown to either NO POWER or LOW POWER respectively. 14. Switch ON the power, key the exciter, and connect a 10 Vdc voltmeter to test point TP4 (P 13-1) on the logic board. Turn R51 (TEMP ALARM SET) until the voltage reads 3.0 Vdc. 15. Unkey the exciter and remove the voltmeter. Caution The low RF alarm trip point is set by one of jumpers JR12 to JR21. This is set to 20% with jumper JR20 at the factory. You may increase this setting in 10% steps from 100% to 10% by installing a jumper at one of the JR positions. The 100% position is jumper JR12, and the 10%position is JR21. WARNING DO NOT install more than one alarm trip point jumper at any time, or else the display driver will be damaged. 16. Switch OFF the power. 17. Install JR26 or JR27 (which ever was installed previously). 18. Disassemble the test equipment, and connect the exciter and power amplifier in its normal configuration.

User's Manual

DSP Exciter USER MANUAL P N 9110 . 0 0172 (old part number = 916-T70A-003) REV N RELEASED Specifications subject to change without notice Copyright © 2011 ISC Technologies All rights reserved. No part of this work may be reproduced or copied in any form or by any means—graphic, electronic, or mechanical, including photocopying, recording, taping, or information-retrieval system—without written permission of ISC Technologies. DSP Exciter Issue 1, Rev. N: 09/25/11
Print Date: 09/25/11 Copyright © 2011 ISC Technologies
Document Change Record Issue 1, Rev. N: 09/25/11 Document Change Record Issue: Rev D Date: 4/25/96 Changes: changed VCO-2 status reading Issue: Rev E Date: 5/14/96 Changes: added Over-The-Link and On-The-Fly information Issue: Rev F Date: 5/23/96 Changes: added one RU space for reinstallation and net channel change time for setup Issue: Rev G Date: 9/03/96 Changes: changed PA fault input pin 11 on Table 4-4 Issue: Rev H Date: 9/20/96 Changes: revised chapter 4 jumper information, added Table 4-5 Issue: Rev I Date: 01/15/97 Changes: added and changed VCO board numbers in Table 3-1 Issue: Rev J Date: 09/22/97 Changes: changed channel select 1 to J4-22, channel select 2 to J4-10, channel select 3 to J4-6 in remote select input vs. channel table; changed channel select 1 to J1-7, channel select 2 to J1-26, and channel select 3 to J1-8 in remote select input vs channel I20 table; changed mode select 2 line to channel select 4 as J1-9, and mode select 1 to J1-27 in remote select input vs. mode I20 table Issue: Rev K Date: 11/12/97 Changes: changed multi-channel adjustment procedure to a reading of 2.8 volts Issue: Rev L Date: 05/14/99 Changes: added nominal powers for different frequency ranges in exciter specifications table Issue: Rev M Date: 07/12/99 Changes: added GL-T8200 to part numbers of VCO/RF amplifier boards table Issue: Rev N Date: 9/25/11 DSP Exciter ISC Technologies Document Number: 9110.00172 Copyright © 2011 ISC Technologies Print Date: 09/25/11
Changes: Changes made to support Narrowband Directive
Table of Contents 1 GENERAL ................................................................................................................... 1-1 1.1 Manual Scope ..................................................................................................... 1-1 1.1.1 Applicable Documents .................................................................... 1-1 1.2 Manual Sections .................................................................................................. 1-1 1.3 Exciter Identification ..................................................................................... 1-1 2 SPECIFICATIONS ..................................................................................................... 2-1 3 DESCRIPTION ........................................................................................................... 3-1 3.1 Introduction ................................................................................................... 3-1 3.2 Physical Description ........................................................................................... 3-1 3.3 Simplified Block-Diagram Description .............................................................. 3-2 4 INSTALLATION AND SETUP ................................................................................. 4-1 4.1 Precautions and Hazards ..................................................................................... 4-1 4.2 Test Equipment and Tools Required ................................................................... 4-1 4.3 Component and Adjustment Locations ............................................................... 4-1 4.4 Installation ..................................................................................................... 4-1 4.4.1 Inspection ........................................................................................ 4-1 4.4.2 Power Requirement ................................................................................ 4-2 4.4.3 Input/Output Connections ............................................................... 4-2 4.4.4 Signal Functions .............................................................................. 4-2 4.4.5 Switches and Jumpers ..................................................................... 4-4 4.5 Setup .............................................................................................................. 4-4 4.6 Ultimate Disposition ........................................................................................... 4-4 5 OPERATION .............................................................................................................. 5-1 5.1 Front-Panel Controls and Indicators .............................................................. 5-1 5.2 Operating Instructions ................................................................................... 5-1 6 THEORY OF OPERATION ...................................................................................... 6-1 6.1 Exciter/PA Control ............................................................................................. 6-1 6.1.1 Reference Source ............................................................................. 6-1 6.1.2 Main Circuit Frequencies ................................................................ 6-1 ISC Technologies Document Number: 9110.00172 DSP Exciter Issue 1, Rev. N: 09/25/11 Table of Contents Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: i
6.1.3 Controller Interface Connector Functions ....................................... 6-1 6.2 Interface to Controller ......................................................................................... 6-3 6.2.1 General ............................................................................................ 6-3 6.2.2 Interface Conversion Functions ....................................................... 6-3 6.3 DSP Modulator ................................................................................................... 6-4 6.3.1 General ............................................................................................ 6-4
Table of Contents Issue 1, Rev. N: 09/25/11 6.3.2 DSP Modulator Signal Flow ................................................................. 6-4 6.4 IF Stage .............................................................................................................. 6-7 6.4.1 Mixer-1 ........................................................................................... 6-7 6.4.2 Filter ............................................................................................... 6-7 6.4.3 VCO-1 ............................................................................................ 6-7 6.4.4 Synthesizer-1 .................................................................................. 6-7 6.5 MCU ................................................................................................................... 6-8 6.5.1 Microcontroller Unit (MCU) .......................................................... 6-8 6.5.2 Digital-to-Analog (D/A) Converter ................................................ 6-9 6.5.3 8/16-Bit Converter .......................................................................... 6-9 6.5.4 Read-Only Memory ............................................................................... 6-9 6.5.5 VSWR-Fault Detector ......................................................................... 6-14 6.5.6 Alarm Data-to-Logic Conversion ........................................................ 6-14 6.6 RF Assemblies .................................................................................................. 6-14 6.6.1 RF Stage Location ........................................................................ 6-14 6.6.2 RF Assemblies .............................................................................. 6-14 6.7 Voltage Regulator Circuit ................................................................................. 6-16 7 MAINTENANCE ....................................................................................................... 7-1 7.1 Location of Maintenance Procedures ................................................................. 7-1 7.2 Test Equipment Required ................................................................................... 7-1 7.3 VCO-2 Adjustment Procedure ........................................................................... 7-1 7.3.1 VCO-2 Multichannel Adjustment Procedure ........................................ 7-1 7.3.2 VCO-2 Single-Channel Adjustment Procedure ..................................... 7-1 7.4 Over-The-Link Downloading ............................................................................. 7-2 7.5 On-The-Fly Channel/Mode Changing ................................................................ 7-2 7.5.1 Programming Example ................................................................... 7-3 7.6 16-Channel Operation ........................................................................................ 7-4 7.7 On-The-Fly Interface .......................................................................................... 7-5 8 CHECKOUT AND TROUBLESHOOTING ........................................................... 8-1 8.1 CHECKOUT ...................................................................................................... 8-1 DSP Exciter ISC Technologies Document Number: 9110.00172 Page: ii Copyright © 2011 ISC Technologies Print Date: 09/25/11
8.2 TROUBLESHOOTING ..................................................................................... 8-1 9 REMOVAL AND REINSTALLATION ................................................................... 9-1 9.1 Exciter/PA Control Chassis ................................................................................ 9-1 9.1.1 Removal Procedure ......................................................................... 9-1 9.1.2 Reinstallation Procedure ................................................................. 9-1 9.2 Exciter Cover ...................................................................................................... 9-2
9.2.1 Removal Procedure ......................................................................... 9-2 9.2.2 Reinstallation Procedure .................................................................. 9-2 9.3 Exciter/Control Board ......................................................................................... 9-5 9.3.1 Removal Procedure ......................................................................... 9-5 9.3.2 Reinstallation Procedure .................................................................. 9-5 9.4 Interface Board ................................................................................................... 9-8 9.4.1 Removal Procedure ......................................................................... 9-8 9.4.2 Reinstallation Procedure .................................................................. 9-8 9.5 VCO/RF Amplifier Board ................................................................................... 9-8 9.5.1 Removal Procedure ......................................................................... 9-9 9.5.2 Reinstallation Procedure .................................................................. 9-9 10 OPTIONS ................................................................................................................. 10-1 10.1 Exciter/PA Control with QT-1000 Interface ................................................... 10-1 10.1.1 Reference Source ............................................................................... 10-1 10.1.2 Controller Interface Connector Functions .......................................... 10-1 10.1.3 QT-1000 Interface Conversion Functions .......................................... 10-1 10.2 Exciter/PA Control with Standard Interface ................................................... 10-5 10.2.1 Reference Source ............................................................................... 10-5 10.2.2 Controller Interface Connector Functions .......................................... 10-6 10.2.3 Standard Interface Conversion Functions .......................................... 10-6 ISC Technologies Document Number: 9110.00172 DSP Exciter Issue 1, Rev. N: 09/25/11 Table of Contents Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: iii
10.3 Exciter/PA Control with I20 Interface ............................................................ 10-9 10.3.1 Reference Source ............................................................................... 10-9 10.3.2 Controller Interface Connector Functions .......................................... 10-9 10.3.3 I20 Interface Conversion Functions ................................................... 10-9
Table of Contents Issue 1, Rev. N: 09/25/11 DSP Exciter ISC Technologies Document Number: 9110.00172 Page: iv Copyright © 2011 ISC Technologies Print Date: 09/25/11
Issue 1, Rev. N: 09/25/11 List of Figures List of Figures Figure 1-1 DSP Exciter Isometric View ......................................................................... 1-2 Figure 3-1 DSP Exciter Rear View ................................................................................. 3-3 Figure 3-2 DSP Exciter Top View with Internal Controls and Indicators ........................................................ 3-4 Figure 3-3 DSP Exciter Simplified Functional Diagram ................................................ 3-5 Figure 4-1 DSP Exciter/PA Control Circuit Boards Interconnection Diagram ........................................................................... 4-5 Figure 5-1 Front-Panel Controls and Indicators .............................................................. 5-2 Figure 6-1 DSP Exciter RF Stage Functional Diagram .................................................. 6-2 Figure 6-2 DSP Exciter MCU Circuit Functional Diagram ............................................ 6-6 Figure 6-3 DSP Exciter-to-Controller Functional Diagram ............................................ 6-10 Figure 6-4 DSP Exciter Detailed Functional Diagram .................................................... 6-12 Figure 6-5 DSP Exciter IF-Stage Detailed Functional Diagram ................................................................................... 6-13 Figure 7-1 On-The-Fly C2000 Control Lines to DSP Exciter ........................................ 7-5 Figure 9-1 DSP Exciter Chassis Removal and Reinstallation ...................................................................................... 9-3 Figure 9-2 DSP Exciter Cover Removal and Reinstallation ...................................................................................... 9-4 Figure 9-3 DSP Exciter Control Board Removal and Reinstallation .............................. 9-7 ISC Technologies Document Number: 9110.00172 DSP Exciter Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: v
Figure 9-4 DSP Exciter External Interface I/O Board Removal and Reinstallation ....................................................................... 9-10 Figure 9-5 DSP Exciter Interface Board Removal and Reinstallation ............................ 9-11
List of Figures Issue 1, Rev. N: 09/25/11 DSP Exciter ISC Technologies Document Number: 9110.00172 Page: vi Copyright © 2011 ISC Technologies Print Date: 09/25/11
Issue 1, Rev. N: 09/25/11 List of Tables List of Tables Table 1-1 Manual Contents ...................................................................................... 1-1 Table 2-1 Exciter Specifications .............................................................................. 2-1 Table 3-1 Part Numbers of VCO/RF Amplifier Boards ........................................... 3-1 Table 3-2 Part Numbers of Interface Boards ............................................................ 3-1 Table 3-3 Part Numbers of Interface I/O Boards ...................................................... 3-2 Table 3-4 Assembly and Control Board Numbers ................................................... 3-2 Table 4-1 Test Equipment Required ......................................................................... 4-1 Table 4-2 DSP Exciter I/O Connectors .................................................................... 4-2 Table 4-3 VT100 Interface Connector J3 Pin Assignments ..................................... 4-3 Table 4-4 Control Board Connector J6 Pin Assignments ......................................... 4-3 Table 4-5 Exciter Control Board Jumper Positions .................................................. 4-4 Table 6-1 Exciter RF/Main Circuit Frequencies ...................................................... 6-1 Table 7-1 Deviation and Offset Programming ......................................................... 7-3 Table 10-1 Interface Board Connector J4 (QT-1000) ................................................... 10-3 Table 10-2 Receiver Connector J5 Pin Functions (QT-1000 with external I/O board) .......................................................... 10-4 Table 10-3 Remote Select Input vs. Channel (QT-1000) .............................................. 10-4 Table 10-4 Remote Select Input vs. Mode (QT-1000) .................................................. 10-5 Table 10-5 Interface Board Connector J4 (Standard) ................................................... 10-7 Table 10-6 Remote Select Input vs. Channel (standard) ............................................... 10-8 Table 10-7 Remote Select Input vs. Mode (standard) ................................................... 10-8 ISC Technologies Document Number: 9110.00172 DSP Exciter Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: vii
Table 10-8 Interface Board Connector J1 ................................................................... 10-10 Table 10-9 Interface Board Connector J2 ................................................................... 10-11 Table 10-10 Remote Select Input vs. Channel (I20) ................................................... 10-12 Table 10-11 Remote Select Input vs. Mode (I20) ....................................................... 10-12
List of Tables Issue 1, Rev. N: 09/25/11 DSP Exciter ISC Technologies Document Number: 9110.00172 Page: viii Copyright © 2011 ISC Technologies Print Date: 09/25/11
Issue 1, Rev. N: 09/25/11 GENERAL 1 GENERAL 1.1 Manual Scope This manual is intended for use as a technical reference guide to the ISC Technologies DSP exciter and contains information on exciter connection, setup, and maintenance. 1.1.1 Applicable Documents Applicable ISC Technologies documents are listed in the applicable system manual. 1.2 Manual Sections Refer to Table 1-1, Manual Contents. Also refer to table of contents in this manual. Table 1-1 Manual Contents section No. and title contents 1 General this section 2 Specifications exciter specifications 3 Descriptions listing of options and assemblies covered, simplified description, physical description, simplified block theory of operation 4 Installation and Setup exciter installation, setup, and lists of connections 5 Operation list, description, and location of operator controls and indicators 6 Theory of Opera- tion assembly-level description of exciter operation 7 Maintenance exciter maintenance 8 Checkout and Troubleshooting exciter checkout and troubleshooting 9 Removal and Re- installation procedures for removing and reinstalling exciter and exciter as- semblies 10 Options list and discussion of user selectable options 1.3 Exciter Identification Refer to Figure Figure 1-1, DSP Exciter Isometric View, for an overall view of the exciter. ISC Technologies Document Number: 9110.00172 DSP Exciter Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 1-1
GENERAL Issue 1, Rev. N: 09/25/11 v 0 2 5 0 . hg l Figure 1-1 DSP Exciter Isometric View DSP Exciter ISC Technologies Document Number: 9110.00172 Page: 1-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
Issue 1, Rev. N: 09/25/11 SPECIFICATIONS 2 SPECIFICATIONS Refer to Table 2-1, Exciter Specifications, which lists the DSP exciter specifications. Where possible, EIA or I-EIS A measuring methods were used in determining specifica-tions. Note that some specifications are not addressed by either set of standards or the prescribed methods were impractical. Table 2-1 Exciter Specifications characteristic condition specification adjacent-channel noise 25-kHz channel spacing, in analog mode -85 dBc 25-kHz channel spacing, in FSK mode -75 dBc alternate channel noise 25-kHz channel spacing -95 dBc spurious -90 dBc operating frequency range determined by installed VCO/RF board refer to Table 3-1 RF output power (mW, nominal) keyed 150 MHz 280 300 450 900 (GL-T8500/GL-T8600) 900 (GL-T8501/GL-T8601) 250 500 1000 300 300 15 carrier frequency stability steady state, -30° to +60° C 10-MHz reference, int=0.005 ppm/yr, ext=0.1 ppm/yr FSK frequency/modulation stability relative to carrier frequency stability +/- 10 Hz max FSK adjustment accuracy +/- 10 Hz analog offset resolution 1 Hz number of channels up to 8, depending on interface board and controller frequency spread 3 MHz at 900 MHz (12 MHz wideband option) 7.5 MHz at 450 MHz 5 MHz at 150 MHz audio input level -25 to +10 dBm (N/A for 138.0-174.0 MHZ & 406.0-470.0 MHz) ISC Technologies Document Number: 9110.00172 DSP Exciter Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 2-1
impedance with transformer 600 ohm or 5 kohms balanced
SPECIFICATIONS Issue 1, Rev. N: 09/25/11 Table 2-1 Exciter Specifications (continued) characteristic condition specification audio response (N/A for 138.0-174.0 MHZ & 406.0-470.0 MHz) flat, 50 to 2800 Hz; not referenced to 1 kHz; 60% deviation +/-0.5 dB preemphasized 6 dB per octave, 300 to 3000 Hz; 60% deviation +/-0.75 dB audio distortion (1-kHz reference at 60% deviation) (N/A for 138.0-174.0 MHZ & 406.0-470.0 MHz) 25-kHz channel spacing less than 1.5% audio response (tracking between units) (N/A for 138.0-174.0 MHZ & 406.0-470.0 MHz) level 0.1 dB max delay 2 usec max FM hum and noise (1-kHz reference at 60% deviation) (N/A for 138.0-174.0 MHZ & 406.0-470.0 MHz) 25-kHz spacing flat, 15-kHz bandwidth -40 dB 25-kHz channel spacing preemphasized, 300 to 3000 Hz -55 dB AM hum and noise standard -34 dB modulation types analog, 2-level FSK, 4-level FSK avail- able with some interfaces (No Analog for 138.0-174.0 MHZ & 406.0-470.0 MHz) channel spacing 6.25 kHz audio-backward compatibility Standard (N/A for 138.0-174.0 MHZ & 406.0-470.0 MHz) emissions FCC 15K0F2D, 16K0F1D, 16K0F3E 9K6F1D for 138.0-174.0 MHZ & 406.0-470.0 MHz 5K60F2D for 138.0-174.0 MHz power requirement 22-29 Vdc less than 3 A humidity noncondensing 0 to 95% relative external 10-MHz reference input level 2Vp-p min impedance 50 ohms spurious above 8 MHz -65 dBc max spurious below 8 MHz -50 dBc max weight 4.8 lb (2.2 kg) dimensions 8.75 in (22.25 cm) d x 19 in (48.25 cm) w x 1.75 in (4.5 cm) h temperature range operating (nonderated) -30° to +60° C storage -55° to +70° C DSP Exciter ISC Technologies Document Number: 9110.00172 Page: 2-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
maximum elevation to 10,000 ft (3050 m)
Issue 1, Rev. N: 09/25/11 DESCRIPTION 3 DESCRIPTION 3.1 Introduction The DSP exciter contains a microprocessor that allows remote or local control of the exciter and consolidates logic for varying degrees of PA control and monitoring through a video display terminal (VDT). Operating characteristics of the exciter are controlled by the selection of hardware options. It is frequency selectable by specifying the appropriate internal frequency determining hardware and software. It is also capable of communicating with several operating protocols through the proper selection of interface boards. 3.2 Physical Description The exciter front panel of one RU (1.75 in) in height contains eight LEDs, two adjustments, and one connector (also see section 5). The exciter chassis is nine inches deep and contains three circuit boards and space for an oscillator (not used with some controllers). Refer to Table 3-1, Part Numbers of VCO/RF Amplifier Boards, which shows subassemblies used for various transmitter operating ranges. ISC Technologies Document Number: 9110.00172 DSP Exciter Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 3-1
DESCRIPTION Issue 1, Rev. N: 09/25/11 Table 3-1 Part Numbers of VCO/RF Amplifier Boards transmitter model VCO/RF-amplifier board frequency band (MHz) VCO board assembly part No. control board assembly part No. GL-T85/8601 929-941 263-0082-072 265-0082-001 936-948 263-0082-070 265-0082-001 924-936 263-0082-069 265-0082-001 GL-T85/8600 900-960 (wb) 263-0082-051/052/053/054/ 055/062 265-0082-024/032 948-960 263-0082-055 265-0082-001 936-948 263-0082-054 265-0082-001 929-941 263-0082-068 265-0082-001 924-936 263-0082-053 265-0082-001 GL-T8200 929-941 263-0082-068 265-0082-001 ISC-T53/5540 406-470 263-0084-003 not yet available GL-T83/8531 320-330 263-0082-049 265-0082-001 GL-T83/8521 275-285 263-0082-047 265-0082-001 ISC-T84/8611 167-175 2100.00094 265-0082-024 162-172 2100.00093 265-0082-024 157-167 2100.00092 265-0082-024 152-162 2100.00091 265-0082-024 147-157 2100.00090 265-0082-024 142-152 2100.00089 265-0082-024 138-148 2100.00088 265-0082-024 Refer to Table 3-2, Part Numbers of Interface Boards. Table 3-2 Part Numbers of Interface Boards DSP exciter-to-controller interface boards interface board part No. QT-1000 interface bd 265-0082-007 standard Interface bd 263-0082-036 I20 interface bd 265-0082-032, 2000.00436 DSP Exciter ISC Technologies Document Number: 9110.00172 Page: 3-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
Issue 1, Rev. N: 09/25/11 DESCRIPTION Refer to Figure 3-1, DSP Exciter Rear View, which shows the exciter rear panel. The back panel contains three BNC-type connectors J3/J7/J8, a DB-15 connector J6, and a terminal board TB 1 as standard items. Other back panel connectors vary depending on which interface and I/O boards are installed. Figure 3-2, DSP Exciter Top View with Internal Controls and Indicators, shows a top view of the exciter with its cover removed. Refer to Table 3-3, Part Numbers of Interface I/O Boards, which shows interface and I/O board part numbers. The I/O boards comprise the means to connect various controllers to the DSP exciter.. Table 3-3 Part Numbers of Interface I/O Boards interface I/O board (control type) interface I/O board part No. QT-1000 Interface I/O bd 261-0082-003 Standard Interface I/O bd 261-0082-004 I20 Interface I/O bd N/A Table 3-4 Assembly and Control Board Numbers exciter assembly No. control board No. Various 265-0082-001 Various 265-0084-024 Various 2000.02090 3.3 Simplified Block-Diagram Description Refer to Figure 3-3, DSP Exciter Simplified Functional Diagram, in the following discus-sion. Inputs from the transmitter controller usually are one or two data bits, two channel-select bits, and keying input. Outputs to the controller are keying output indicator, various ISC Technologies Document Number: 9110.00172 DSP Exciter Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 3-3
fault outputs, forward-power sample, and reflected-power sample.
DESCRIPTION Issue 1, Rev. N: 09/25/11 v 0 3 4 3 . hg l Figure 3-1 DSP Exciter Rear View DSP Exciter ISC Technologies Document Number: 9110.00172 Page: 3-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
Issue 1, Rev. N: 09/25/11 DESCRIPTION v 0 3 4 4 . hg l ISC Technologies Document Number: 9110.00172 DSP Exciter Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 2-5 (N/A for 138.0-174.0 MHZ & 406.0-470.0 MHz)
DESCRIPTION Issue 1, Rev. N: 09/25/11 v 0 2 5 1 . hg l Figure 3-3 DSP Exciter Simplified Functional Diagram DSP Exciter ISC Technologies Document Number: 9110.00172 Page: 2-6 Copyright © 2011 ISC Technologies Print Date: 09/25/11
4 INSTALLATION AND SETUP 4.1 Precautions and Hazards Caution PC boards within this assembly use static-sensitive components. Follow IC-handling precautions. Caution The exciter contains internal memory which is used to characterize exciter operation. Upon exciter replacement, ensure that replacement exciter contains appropriate items in its memory. 4.2 Test Equipment and Tools Required Table 4-1, Test Equipment Required, lists required test equipment. Common hand tools may also be required for most procedures. Table 4-1 Test Equipment Required item description tuning tool Johanson 8777 or equivalent RF power meter Bird model 8327 or equivalent with appropriate RF adapters voltmeter Fluke model 77 DVM or equivalent RF dummy load 50-ohm load 4.3 Component and Adjustment Locations Figure 3-3, DSP Exciter Simplified Functional Diagram, shows the location of assemblies, internal user-adjustable controls, and I/O locations. Note that most adjustments are performed via the front-panel VT100 interface. 4.4 Installation 4.4.1 Inspection Inspect exciter to ensure air flow is not obstructed and cables and wires are securely fastened to their respective connectors. ISC Technologies Document Number: 9110.00172 DSP Exciter Issue 1, Rev. N: 09/25/11 INSTALLATION AND SETUP Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 4-1
4.4.2 Power Requirement The DSP exciter, when used as a component of a transmitter, draws its power from system wiring. Current draw is less than three amperes at 22 to 29 volts. It is normally powered by the transmitter power supply but can be powered by an auxiliary supply. 4.4.3 Input/Output Connections Figure 3-3, DSP Exciter Simplified Functional Diagram, shows the locations of I/O connectors; Table 4-2, DSP Exciter I/O Connectors, lists I/O connectors and describes their functions. Normally the exciter is delivered as part of an entire transmitter and has already been installed in a rack, with all connections already made, except for connections to equipment that was not installed in the rack before shipment. If I/O connections are required, refer to the system-interconnect diagram and other instructions in the transmitter manual. 4.4.4 Signal Functions See Table 4-2, DSP Exciter I/O Connectors, which references other tables that describe pinby-pin functions of multipin connectors. Figure 4-1, DSP Exciter/PA Control Circuit Boards Interconnection Diagram, shows interconnections among internal assemblies. Table 4-2 DSP Exciter I/O Connectors stencil/connector description additional detail VT100 INTERFACE: J3 VT100 interface to VDT (front) Table 4-3 RF OUT: J3 RF out, on frequency Figure 6-1 QT-1000 interface I/O J4 interface to QT-1000 interface board Table 10-1 QT-1000 interface I/O J5 DB-9 connector, to receiver Table 10-2 standard interface I/O J4 interface to standard interface I/O board Table 10-1 GL-C2000 interface I/O J4 interface to GL-C2000 interface I/O board PA CONTROL: J6 connects to PA Table 4-4 ISOLATOR IN: J7 VSWR input from PA Figure 3-1 10 MHZ IN: J8 external reference input from interface Figure 3-1 +26 VDC: TB1 exciter input power, +22-29 Vdc Figure 3-1 DSP Exciter ISC Technologies Document Number: 9110.00172 INSTALLATION AND SETUP Issue 1, Rev. N: 09/25/11 Page: 4-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
Table 4-3 VT100 Interface Connector J3 Pin Assignments J3-X (front) signal description 2 TXD transmit data line 3 RXD receive data line 5 GND ground 1,4,6,7,8,9 not used Table 4-4 Control Board Connector J6 Pin Assignments J6-X signal description J6-X signal description 1 A/D1+ multiplex analog input from PA No. 1 multiplexer 9 A/D2+ multiplex analog input from PA No. 2 multi- plexer 2 A/D3+ multiplex analog input from PA No. 3 multiplexer 10 A/D4+ multiplexed analog input from PA No. 4 multi- plexer 3 AGC REF+ GC reference voltage output to PA, 1-12 Vdc 11 PA FAULT PA fault input, HI=fault 4 PA GROUND no connection 12 PA GROUND no connection 5 PA GROUND no connection 13 INPUT SELECT 1 one of four select outputs to PA multiplexers, LO=20 digit enabled for mux input decoder 6 INPUT SELECT 2/ KEY OUT one of four select out- puts to PA multiplexers, LO=21 14 INPUT SELECT 3 one of four select outputs to PA multiplexers, LO=22 digit enabled for mux input decoder 7 INPUT SELECT 4/ KEY OUT one of four select out- puts to PA multiplexers, not used 15 AUX LATCH ENABLE latch-enable output to PA multiplexers, LO=mux input decoder reads the three select inputs 8 REF SAMPLE reflected power sample input from PA ISC Technologies Document Number: 9110.00172 DSP Exciter Issue 1, Rev. N: 09/25/11 INSTALLATION AND SETUP Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 4-3
4.4.5 Switches and Jumpers Figure 3-2, DSP Exciter Top View with Internal Controls and Indicators, shows the locations of user-adjustable switches and jumpers. Refer to Table 4-5 for a list of software related jumper positions found on the exciter/control board. No switches are available to maintenance personnel. Table 4-5 Exciter Control Board Jumper Positions Jumper pre version 2.10 software version 2.10 software JW 1 set to A for external 10 MHz oscillator set to A for external 10 MHz oscillator set to B for internal 10 MHz oscillator set to B for internal 10 MHz oscillator JW2 set to A for password protection set to A for password protection set to B to bypass password protection set to B to bypass password protection JW3 set to A for external VSWR protection always set to B (for internal and/or ex- ternal VSWR protection) set to B for internal VSWR protection 4.5 Setup Note When doing a setup for a wideband DSP exciter, the net channel change time must be set for 300 ms. Refer to the DSP exciter VDT Menus and user manual for transmitter-control setup infor-mation. All setup is done via the front-panel VT100 interface. 4.6 Ultimate Disposition Caution This equipment may contain hazardous materials. Check with the local EPA or other environmental authority before disposing of this equipment. DSP Exciter ISC Technologies Document Number: 9110.00172 INSTALLATION AND SETUP Issue 1, Rev. N: 09/25/11 Page: 4-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
v 0 1 6 4 . hg l Figure 4-1 DSP Exciter/PA Control Circuit Boards Interconnection Diagram ISC Technologies Document Number: 9110.00172 DSP Exciter Issue 1, Rev. N: 09/25/11 INSTALLATION AND SETUP Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 4-2 P9 P4 P4 P1 J1 J2 J3 J3
DSP Exciter ISC Technologies Document Number: 9110.00172 INSTALLATION AND SETUP Issue 1, Rev. N: 09/25/11 Page: 4-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
5.1 Front-Panel Controls and Indicators Refer to Figure 5-1, Front-Panel Controls and Indicators, which shows and describes front-panel indicators. The DSP exciter contains no front-panel controls. A front-panel access to VCO adjustment is for maintenance purposes only. 5.2 Operating Instructions The transmitter controller operates the exciter and transmitter in an unattended manner during normal system operation. The VT100 interface with a VDT enables the maintenance technician to perform maintenance and observe operational parameters. Refer to the DSP exciter VDT Menus and user manual for detailed operating information. ISC Technologies Document Number: 9110.00172 DSP Exciter Issue 1, Rev. N: 09/25/11 OPERATION 5 OPERATION Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 5-1
OPERATION Issue 1, Rev. N: 09/25/11 v 0 0 7 9 . hg l Figure 5-1 Front-Panel Controls and Indicators DSP Exciter ISC Technologies Document Number: 9110.00172 Page: 2-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
6 THEORY OF OPERATION 6.1 Exciter/PA Control Refer to Figure 6-1, DSP Exciter RF Stage Functional Diagram, which describes the signal flow in the DSP exciter with the transmitter controller interface. The following major para-graphs describe the operation of the major items within the figure. Additional detailed figures are referenced, as required. 6.1.1 Reference Source The ten-MHz reference signal is provided by the transmitter controller or by an optional internal reference oscillator. All other inputs and outputs, except for RF output, are routed through the interface board. 6.1.2 Main Circuit Frequencies The VCO/RF amplifier board installed determines the frequency for the RF output. Table 6-1, Exciter RF/Main Circuit Frequencies lists VCO/RF amplifier board frequencies and the corresponding exciter/output frequencies. Table 6-1 Exciter RF/Main Circuit Frequencies exciter output frequency (MHz) first IF frequency (kHz) second IF frequency (MHz) VCO-1 frequency (MHz) VCO-2 frequency (MHz) 900-960 100 90 89.9 810-870 445-470 100 90 89.9 355-380 275-330 100 90 89.9 365-420 130-180 100 90 89.9 220-270 6.1.3 Controller Interface Connector Functions Refer to Table 4-2, DSP Exciter I/O Connectors and subsequent tables for a pin-by-pin description of signal functions. The exciter interfaces with the transmitter controller through the exciter interface I/O board. Connector P4 on the internal interface board connects directly to J4 on the exciter. Alarm signals, consisting of transmitter alarm, fault, and status signals, are supplied directly to the transmitter controller. ISC Technologies Document Number: 9110.00172 DSP Exciter Issue 1, Rev. N: 09/25/11 THEORY OF OPERATION Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 6-1
THEORY OF OPERATION Issue 1, Rev. N: 09/25/11 v 0 1 2 3 . hg l Figure 6-1 DSP Exciter RF Stage Functional Diagram DSP Exciter ISC Technologies Document Number: 9110.00172 Page: 6-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
6.2 Interface to Controller 6.2.1 General The controller interface is the portion of exciter circuitry that connects the transmitter controller to the exciter. The interface board dictates what kind of transmitter controller may operate the transmitter. The transmitter can be operated through one of several control-lers depending on which interface board is installed in the exciter. The internal interface board may also exhibit an external I/O board. Control commands from the transmitter controller are connected through the interface circuit. This circuit supplies remote control to the microcontroller unit (MCU) control circuit. The VT-100 VDT supplies local control. The MCU control circuit generates all control signals for the other circuits, and monitors their status. The MCU control circuit reports status back to the VT-100 VDT and the interface circuit, which supplies the status to the transmitter controller. 6.2.2 Interface Conversion Functions Some signals exchanged between the controller and the exciter originate with a format, voltage, or requirement incompatible with their destination. The interface performs any signal conversions necessary to provide compatibility between the controller and the exciter. None, some, or all of the following conversion functions may be done by any one particular interface board. 6.2.2.1 Analog-Mode A/D Conversion (N/A for 138.0-174.0 MHz & 406.0-470.0 MHz The DSP modulator circuit reads synchronized serial data for its analog mode input signal. if the transmitter controller provides an analog signal, the controller interface converts the analog to the appropriate data form for the DSP. The analog (FLAT AUDIO+, -) terminates across a balanced input circuit that also provides a level adjustment. The adjustment, when properly set by the AUDIO INPUT ADJUST pot through the exciter cover, provides analog to an A/D converter at the optimum zero-dBm level. The A/D converts the analog into serial data, which is applied to the DSP through a synchronous data link. A synchronous data link is characterized by an exchange of pulse streams for timing purposes. The A/D converter is clocked by a pulse generator circuit driven by the ten-MHz reference circuit. 6.2.2.2 FSK-Data-Bit Strapping The DSP modulator circuit can read up to four bits for its digital FSK mode input signal. If the controller provides only bit 1 (DATA 1), operation in the four-level mode or higher is precluded. Bits 2 through 4 (DATA2 through DATA4) are available as FSK data inputs; whether they are used or not is a function of the particular controller interface used and the transmitter controller. Refer to Section 10. The controller interface disables unused bits by ground straps. ISC Technologies Document Number: 9110.00172 DSP Exciter Issue 1, Rev. N: 09/25/11 THEORY OF OPERATION Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 6-2
6.2.2.3 Channel-Select-Bit Strapping The MCU control circuit reads three bits to determine the remotely selected channel. If the controller provides only bits 1 and 2 (CH SEL 1, 2), the controller can command only four channels. The operation of bit 3 is a function of the controller interface. Refer to Section 10. 6.2.2.4 Mode-Select-Bit Strapping The MCU control circuit reads two bits to determine the remotely selected mode. If the controller provides only bit 1 (MODE CONTROL), the controller can command only two transmitter modes. The operation of bit 2 is a function of the controller interface. Refer to Section 10. If the controller interface does not use bit 2, it straps it to ground (low). 6.2.2.5 Power Sample D/A Conversion The controller reads sample voltages for its forward and reflected power sample inputs, which are stored as data in the MCU control circuit. In some cases the controller interface converts the data to voltages of the appropriate range for the controller. Data from the MCU representing the forward and reflected powers is written into a dual D/A converter, which converts the data into two proportional dc voltages, which are applied to the controller. Control logic gates ensure that data is written to the proper half of the D/A converter. 6.3 DSP Modulator 6.3.1 General The DSP modulator circuit converts the data into the first IF signal, which is fully modu-lated. The IF stage circuit converts the first IF signal into the second IF signal. The RF stage circuit converts the second IF signal into the RF output. Ten MHz is used as frequency reference by each conversion stage. The DSP modulator is the portion of exciter circuitry between the controller interface and the IF stage. The DSP modulator uses digital signal processing to modulate and up-convert the paging information into the first IF signal. The modulation type depends on the transmitter operating mode. The IF stage is the portion of exciter circuitry between the DSP modulator and the RF stage. The IF stage uses hetero-dyne mixing to generate the optimum second IF signal frequency, which depends on the requirement of the VCO/RF amplifier board installed. The MCU control circuit is the command and control hub of the transmitter. The type of control software depends on the transmitter frequency and power output. The following text describes main exciter circuitry that works for all software programs, modulation schemes, and IF signal frequencies. Figure 6-2, DSP Exciter MCU Circuit Functional Diagram shows additional details. 6.3.2 DSP Modulator Signal Flow Refer to Figure 6-2, DSP Exciter MCU Circuit Functional Diagram, in the following discussion. The inputs that provide the paging information to the DSP modulator circuit are digitized audio and FSK data, supplied by the controller interface circuit through connector pair P 1/J1. Digitized audio arrives as serial data. FSK data arrives as parallel data. The DSP modulator circuit processes the digitized audio in the analog mode or the FSK data in the digital mode. The result of this processing is the exciter’s first IF signal, which is applied DSP Exciter ISC Technologies Document Number: 9110.00172 THEORY OF OPERATION Issue 1, Rev. N: 09/25/11 Page: 6-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
to the IF stage circuit. To produce the first IF signal, the DSP modulator contains two DSPs (a signal modulator and a quadrature modulator), a digital-to-analog converter, and a read-only memory. The following text describes these four components and their signal flow. 6.3.2.1 Digital Signal Modulator The signal modulator (SM) generates modulation that contains the paging information, which is supplied by digitized audio or FSK data. The digitized audio is input into a serial input port. An external edge detector is required to input the FSK data. The SM converts one of the data inputs into a modulated signal, which is mathematically represented within the SM as a vector signal, defined by its rectangular coordinates. These coordinates, commonly known as I and Q, are supplied to the digital quadrature modulator as 16-bit parallel data. The modulated signal output from the SM depends on the following signal characteristics:  modulation scheme  frequency response or rise time  input logic or data inversion  deviation level or bandwidth  offset from carrier frequency  analog gain and deviation limit The SM also performs all communications between the DSP modulator circuit and the MCU control circuit. These communications are through the SM 16-bit parallel data port. External input and output latches expand the capabilities of this port. Control inputs consist of commands such as reset, request status, set paging signal parameter, change mode, and boot program. Requested status outputs consist of current mode, deviation levels, input level, input gain, modulation detected, and current polarity. Nonrequested status outputs indicate the existence of analog limiting and modulation. 6.3.2.2 Digital Quadrature Modulator The digital quadrature modulator (DQM) performs interpolation and up-conversion of the modulated signal. The modulated signal input to the DQM is applied by the SM as I and Q components (16-bit parallel data). The DQM performs trigonometric computations at a much higher sampling rate, which determines the first IF signal value and frequency. The modulated signal output from the DQM is supplied from its serial data port to the D/A converter. 6.3.2.3 Digital-to-Analog Converter The digital input to the digital-to-analog (D/A) converter is the modulated signal from the DQM. This data arrives as serial data. The analog output from the D/A converter is the first IF signal. In addition to the IF stage circuit, the first IF signal is supplied to the MCU control circuit, where it is rectified and filtered to generate fault logic. ISC Technologies Document Number: 9110.00172 DSP Exciter Issue 1, Rev. N: 09/25/11 THEORY OF OPERATION Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 6-2
v 0 0 8 3 . hg l7 Figure 6-2 DSP Exciter MCU Circuit Functional Diagram DSP Exciter ISC Technologies Document Number: 9110.00172 THEORY OF OPERATION Issue 1, Rev. N: 09/25/11 Page: 6-6 Copyright © 2011 ISC Technologies Print Date: 09/25/11
6.3.2.4 Read-Only Memory A programmable and erasable read-only memory (PEROM) stores the modulator programs for both DSPs. These programs are transferred to the SM when the exciter is booted up (powered up), then the SM transfers the program to the DQM. The nonvolatile PEROM retains its program for years. Its memory may be individually reprogrammed without erasing the entire chip. 6.4 IF Stage Refer to Figure 6-1, DSP Exciter RF Stage Functional Diagram. The input to the IF stage is the first IF signal, which is supplied by the DSP modulator circuit. The first IF signal carries all the paging information on an intermediate carrier frequency. The IF stage performs direct up-conversion of the first IF signal to create the second IF signal, which carries the same paging information as the first IF signal, but on a higher carrier frequency. The second IF signal is applied to the RF stage through connector pair J10/P 10. To produce the second IF signal, the IF stage contains mixer-1 and filter circuits. Supporting these circuits are VCO-1 and synthesizer-1 circuits. Figure 6-2, DSP Exciter MCU Circuit Func-tional Diagram, and Figure 6-3, DSP Exciter-to-Controller Functional Diagram, show additional detail. 6.4.1 Mixer-1 Mixer-1 is the first heterodyne mixer. Inputs to mixer-1 are a modulated IF and a carrier. The modulated IF input is the first IF signal. The carrier input is supplied by VCO-1. The output from mixer-1 consists of two modulated carriers that are sums and difference frequencies of the inputs. These two frequencies are applied to the filter circuit. 6.4.2 Filter The filter is centered at the second IF signal frequency with a 45-kHz bandwidth. The input to the filter consists of two modulated carriers. These are sum and difference frequencies supplied by mixer-1. The output from the filter is only the sum frequency. This modulated output is the second IF signal. 6.4.3 VCO-1 VCO-1 is the local oscillator for the IF stage. The input to VCO-1 is a dc control voltage. This voltage controls VCO-1 carrier frequency and is supplied by synthesizer-1. The output from VCO-1 is a sine-wave carrier. The output is applied to mixer-1. 6.4.4 Synthesizer-1 Synthesizer-1 controls VCO-1 carrier frequency by means of a phase-locked loop (PLL). PLL inputs are a carrier and a phase reference. The reference input is a ten-MHz carrier supplied by the ten-MHz reference circuit. The carrier input is from VCO-1. The PLL output is a dc control voltage. This voltage, set to cause the VCO-1 carrier to lock phases with the reference, is supplied to VCO-1. ISC Technologies Document Number: 9110.00172 DSP Exciter Issue 1, Rev. N: 09/25/11 THEORY OF OPERATION Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 6-2
Synthesizer-1 also performs all communications between the IF stage circuit and the MCU control circuit. A control input specifies the VCO-1 carrier frequency; this data is received over a serial data link when the exciter is booting or changing channels. Status outputs are a lock fault and a VCO1 level. The lock fault indicates loss of the carrier/reference phase lock. The VCO1 level is the VCO-1 control voltage. 6.5 MCU Refer to Figure 6-4, DSP Exciter Detailed Functional Diagram. Control outputs are supplied by the MCU control circuit to the other functional circuits. Likewise, status inputs are applied to the MCU control circuit from the other functional circuits. Discussions of these control and status signals are included with the information on the other major func-tional circuits. To interface these control and status signals, the MCU control circuit contains an MCU, D/A converter, 8/16 bit converter, read-only memory, and a VSWR-fault detector. To light the front-panel LEDs, the MCU control circuit contains a bank of PNP switching transistors. Refer to Figure 6-2, DSP Exciter MCU Circuit Functional Diagram, in the following text which describes this circuitry and its signal flow. 6.5.1 Microcontroller Unit (MCU) The MCU contains a central processing unit (CPU), memories, peripherals, and other hardware on a single chip. The primary internal functions of the MCU and their application in the exciter are described in the following list.  An eight-bit remote input port accepts discrete low power mode, emission mode, keyline, and channel selects from the controller interface circuit. An external edge detector is required to input the channel selects.  Interrupt logic stops RF transmission when a fault or reset input is received, e.g. a VSWR or PA fault.  An on-board oscillator/clock generator, driven by an external crystal, times internal MCU functions. A synchronized clock output times external functions.  The MCU performs most interfacing through a parallel communications link: eight-bit data bus, sixteen-bit address bus, and a read/write line. External input and output latches expand the capability of this link.  An eight-bit input/output port supplies discrete keyline, RF status, and chip select controls to the exciter and the PA.  A serial peripheral interface (SPI) supplies synchronous serial frequency data to the IF stage and RF stage circuits. Individual commands load the program into either IF stage’s synthesizer-1 or RF stage synthesizer-2.  An 8-input analog-to-digital (A/D) converter measures voltage inputs from the exciter and the PA. An external multiplexer expands MCU analog inputs to fifteen.  A serial communications interface (SCI) exchanges asynchronous serial RS-232 data with the VT-100 VDT. An external RS-232 driver buffers the MCU data, allowing it to be exchanged through external connector J3.  A random-access memory (RAM) temporarily stores transmitter fault and alarm values. DSP Exciter ISC Technologies Document Number: 9110.00172 THEORY OF OPERATION Issue 1, Rev. N: 09/25/11 Page: 6-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
• An electrically-erasable read-only memory (EEPROM) permanently stores transmitter signal parameters. 6.5.2 Digital-to-Analog (D/A) Converter A D/A converter generates an AGC reference voltage. The D/A converter inputs are data and select logic. The data, supplied by the MCU when the D/A is selected, represents the desired transmitter power output. The D/A converter output is an AGC reference voltage. This voltage represents a level proportional to the desired transmitter power output. The AGC reference voltage, output through connector J6, is used by the PA to generate an AGC voltage. 6.5.3 8/16-Bit Converter An 8/16-bit converter allows the MCU eight-bit data bus to communicate with the 16-bit data bus of the DSP modulator circuit. The MCU must perform two read or write proce-dures, a low byte and a high byte, to each one of the DSP modulator circuit. The converter provides two status outputs to the MCU and the DSP modulator circuit. A data-availableto-MCU status indicates that the DSP modulator circuit has written data into the converter that the MCU must read. A data-available-to-DSP status indicates that the MCU has written data into the converter that the DSP modulator circuit must read. In the event that the DSP modulator circuit does not read data that the MCU has written, a DSP communications fault is generated. 6.5.4 Read-Only Memory A programmable and erasable read-only memory (PEROM) stores the control program for the transmitter. This program is transferred to the MCU when the exciter is booted up. The nonvolatile PEROM retains its program for years. Its memory may be individually repro-grammed without erasing the entire chip. ISC Technologies Document Number: 9110.00172 DSP Exciter Issue 1, Rev. N: 09/25/11 THEORY OF OPERATION Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 6-2
Figure 6-3 DSP Exciter-to-Controller Functional Diagram v 0 34 5l 7 DSP Exciter ISC Technologies Document Number: 9110.00172 THEORY OF OPERATION Issue 1, Rev. N: 09/25/11 Page: 6-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
v 0 3 4 5R .h g l ISC Technologies Document Number: 9110.00172 DSP ExciterIssue 1, Rev. N: 09/25/11 THEORY OF OPERATION J1
Figure 6-3 DSP Exciter-to-Controller Functional Diagram (Continued) Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 6-2
v0081.hgll Figure 6-4 DSP Exciter Detailed Functional Diagram DSP Exciter ISC Technologies Document Number: 9110.00172 THEORY OF OPERATION Issue 1, Rev. N: 09/25/11 Page: 6-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
v 0 07 7. hg lr Figure 6-5 DSP Exciter IF-Stage Detailed Functional Diagram ISC Technologies Document Number: 9110.00172 DSP Exciter Issue 1, Rev. N: 09/25/11 THEORY OF OPERATION Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 6-2
6.5.5 VSWR-Fault Detector The exciter receives a VSWR signal from the PA through connector J7. This signal is a rectified dc voltage sample generated by the isolator. The voltage sample is monitored by the MCU to provide the value for the total reflected-power indication. The voltage sample is also monitored by a fault circuit in the exciter. If a factory-preset voltage is exceeded, the fault circuit shuts down the transmitter by an interrupt to the MCU. 6.5.6 Alarm Data-to-Logic Conversion The transmitter controller reads logic alarm inputs; most of these alarms are stored as data in the MCU control circuit. If the controller interface converts the data to individual logic signals for the controller, data from MCU control representing the alarms is clocked into a pair of latches. The latches convert the data into continuous logic signals. These signals and others control a bank of NPN switching transistors that supply the actual logic signal to the controller. Control logic gates convert chip controls from the MCU into a clock input for the latches. 6.6 RF Assemblies 6.6.1 RF Stage Location Refer to Figure 3-3, DSP Exciter Simplified Functional Diagram, to locate the assembly. The RF stage circuits are located on two circuit boards, both housed within the exciter chassis.The exciter/control board is the main circuit board and the VCO/RF amplifier board is a selected option. The exciter/control board connects to the VCO/RF amplifier board through three connector pairs: J4/P4, J9/P9, and J10/P10. The VCO/RF amplifier board also contains BNC connector J3, which extends through the rear panel of the exciter. This board contains most of the RF stage components inside an RF shield. A hole in the shield and the front panel provide access to an RF stage adjustment, which is marked VCO ADJ on the front panel. 6.6.2 RF Assemblies 6.6.2.1 RF Stage Description The RF stage is the portion of exciter circuitry between the IF stage and RF out and is the final maj or functional circuit, the RF stage determines the transmitter RF output frequency, and dictates the highest and lowest possible RF output frequencies (RF band). The trans-mitter can be operated at several RF bands, depending on the RF stage circuitry installed in the exciter. 6.6.2.2 RF Stage Bands The selected VCO/RF amplifier board determines the RF band of the transmitter. Table 3-1, Part Numbers of VCO/RF Amplifier Boards, lists the RF bands and the part number of the board with that RF band. DSP Exciter ISC Technologies Document Number: 9110.00172 THEORY OF OPERATION Issue 1, Rev. N: 09/25/11 Page: 6-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
6.6.2.3 RF Stage Signal Flow Refer to Figure 6-1, DSP Exciter RF Stage Functional Diagram. The input to the RF stage is the second IF signal, supplied by the IF stage circuit through connector pair J10/P 10. The second IF signal carries the paging information on a modulated carrier at the exciter’s second intermediate frequency. The RF stage converts the second IF signal into the exciter’s RF output. This RF output carries the same paging information as the second IF signal, but on a modulated carrier of radio frequency. The RF output is normally applied to the PA through connector J3. To produce the RF output, the RF stage contains mixer-2, a filter, and an amplifier. Supporting these circuits are VCO-2 and synth-2. The following text describes these five circuits and their signal flow. 6.6.2.3.1 Mixer-2 Mixer-2 is the second heterodyne mixer. Inputs to mixer-2 are a modulated IF and a carrier. The modulated IF is the second IF signal. The carrier is supplied by VCO-2. Output from mixer-2 consists of sum and difference frequencies of the inputs. The sum frequency is centered near the channel carrier, and the difference frequency about twice the second IF frequency below that. These two modulated RF carriers are applied to the filter circuit. 6.6.2.3.2 Filter The filter is factory-selected and tuned, with a bandwidth determined by carrier frequency of the transmitter. The inputs to the filter consist of two modulated RF carriers and a key control.The two carriers are sum and difference frequencies, supplied by mixer-2. The key control is supplied by the MCU control circuit through J4/P4. The output from the filter, supplied when the key control is received, is only the sum frequency. This modulated RF, centered near the channel on-frequency, is supplied to the amplifier. 6.6.2.3.3 Amplifier The amplifier provides amplification to the value listed in the specifications as exciter RF power out. The inputs to the amplifier consist of modulated RF and a key control. The modulated RF, mixer-2 sum output frequency, is supplied through the filter. Key control is supplied by the MCU control circuit through J4/P4. Output from the amplifier, supplied when the key control is received, is an amplified version of the modulated RF. This amplified output is the exciter RF output. 6.6.2.3.4 VCO-2 VCO-2 is the RF stage local oscillator. Inputs to VCO-2 are a dc control voltage and an adjustment. Dc control voltage is supplied by synthesizer-2. The adjustment, which varies the VCO2 control voltage level, is controlled through the front-panel VCO ADJ access. This control provides the means for VCO-2 to output a carrier frequency that would otherwise be beyond the range of the control voltage input. The carrier output, always second IF frequency below the channel carrier frequency, is applied to mixer-2. ISC Technologies Document Number: 9110.00172 DSP Exciter Issue 1, Rev. N: 09/25/11 THEORY OF OPERATION Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 6-2
6.6.2.3.5 Synthesizer-2 Synthesizer-2 controls VCO-2 carrier frequency by means of a phase-locked loop (PLL). PLL inputs to synthesizer-2 are a carrier and a phase reference. The reference is a ten-MHz carrier supplied by the ten-MHz reference circuit. The carrier is the VCO-2 output. The PLL output from synthesizer-2 is a dc control voltage. This voltage, set to cause VCO-2 to lock phases with the reference, is applied to the VCO-2 control input. Synthesizer-2 also performs all communications between the RF stage circuit and the MCU control circuit. A control input to synthesizer-2 specifies VCO-2 carrier frequency. This data is received over a serial data link when the exciter is booting or changing channels. Status outputs from synthesizer-2 are a lock fault and a VCO2 level. The lock fault indicates loss of the carrier/reference phase lock. VCO2 level is the VCO-2 control voltage. 6.7 Voltage Regulator Circuit Refer to Figure 6-4, DSP Exciter Detailed Functional Diagram (center, toward bottom) in the following discussion. The exciter receives 26-volt operating power through terminal board TB 1. The dc power indicator on the exciter front panel is connected to this input. This voltage is supplied to a 26-volt bus and is monitored by the MCU. An intermediate regulator reduces the 26 volts to 16.5 volts, which is supplied to the two final regulators. One regulator generates 13.5 volts, which is supplied to a 13.5-volt bus and monitored by the MCU. The other regulator generates 5 volts, which is supplied to a five-volt bus and monitored by the MCU. DSP Exciter ISC Technologies Document Number: 9110.00172 THEORY OF OPERATION Issue 1, Rev. N: 09/25/11 Page: 6-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
7 MAINTENANCE 7.1 Location of Maintenance Procedures The DSP exciter is central to performing transmitter maintenance. Most maintenance of electrical assemblies is done via the VT100 interface. Any maintenance procedures which require adjusting controls within the exciter chassis are listed in this section. Replace the exciter if it has input power, as indicated by the front-panel LED, but does not allow the user to make connection via the VT100 interface. 7.2 Test Equipment Required Table 4-1, Test Equipment Required, lists test equipment required to perform maintenance procedures. 7.3 VCO-2 Adjustment Procedure Perform the VCO-2 adjustment procedure after installing new VCO/RF amplifier board or after setting new channel carrier frequency. If the transmitter is to operate at more than one frequency, perform the multichannel adjustment procedure. If the transmitter is to operate at only one frequency, perform the single-channel adjustment procedure. Refer to the DSP exciter VDT manual as necessary. 7.3.1 VCO-2 Multichannel Adjustment Procedure 1. Set up VT-100 VDT and select local control (see VDT manual). 2. Select transmitter channel of lowest frequency if not already selected. 3. Use tuning tool supplied to adjust VCO AD J control through exciter front panel. Ad-just for a reading of 2.8 volts (3.5 volts for wideband VCO 263-0082-062), on VCO2 status display. 4. Return transmitter to service. Procedure is complete. 7.3.2 VCO-2 Single-Channel Adjustment Procedure This procedure does not apply to wideband option. 1. Set up VT-100 VDT and select local control (see VDT manual). 2. Select transmitter channel of operating frequency if not already selected. 3. Use tuning tool supplied to adjust VCO ADJ control through exciter front panel. Ad-just for reading of 5.0 Vdc on VCO2 status display. 4. Return transmitter to service. Procedure is complete. ISC Technologies Document Number: 9110.00172 DSP Exciter Issue 1, Rev. N: 09/25/11 MAINTENANCE Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 7-2
7.4 Over-The-Link Downloading Over-the-link (OTL) code downloading allows C2000 transmitter controller (C2000) software, alarm matrix setup, and exciter software to be downloaded over the C2000 link channel. To properly use OTL downloading, C2000 units must be programmed for the correct control group, site ID, and unit ID, which are integral to C2000 hardware and software. When information is downloaded over the link channel, the control group, site IDs and/or unit IDs that are to receive the code must be specified. Caution If the control group, site ID, and unit ID are not specified, all units in the system accept the download information. In a mixed system, this can result in some of the transmitters being off the air. An example of this would be a GL-T8600 exciter receiving a GL-T8500 exciter programming code. The GL-T8600 exciter would not operate with this software and could result in a site visit to correct the problem. Programming of control groups and site IDs is done via the C2000 front port with a local connection or through a modem from a remote location. The control groups should be setup as a group of transmitters having the same configuration. For example, all GL-T8500 trans-mitters could be in one control group and GL-T8600 transmitters be in another. This would allow one to download exciter software to all GL-T8500 transmitters at one time by selecting their control group. Any transmitter with a different control group would not accept the download information. Site ID must be different for each site location, and is used when downloading information to a specific site location. If there are multiple units at the same site, the site ID and unit ID need to be specified to download to a specific unit. If the unit ID is not specified, all units at that site accept the download. Unit ID is programmed with a rotary switch in the C2000; it must be different for each C2000 at a site location. To download one specific unit, both site and unit ID must be specified for that unit; the unit with that site ID and unit ID is the only one that accepts the download. For assistance on how to perform a download, call ISC Technologies customer support at 217-221-0985. 7.5 On-The-Fly Channel/Mode Changing Different paging formats may require different digital deviation and offsets of paging data on the same RF carrier frequency. In the past, the only way to meet the different deviation requirements on the same frequency was to program two different channels for the same RF carrier frequency and then program those same two channels for a different digital DSP Exciter ISC Technologies Document Number: 9110.00172 MAINTENANCE Issue 1, Rev. N: 09/25/11 Page: 7-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
deviation and offset. By changing channels, the deviation requirements of the paging formats were met. However, a channel change requires that the transmitter be unkeyed to allow time for PLL lock-up, which is a loss of air time. The on-the-fly feature allows the following:  Each channel can be programmed for four different digital modes (A, B, C, D)  Each mode allows different digital deviation and offsets to be programmed During normal paging operation, the C-2000 controller sends information to the transmitter telling it what channel to operate on and which one of the four digital modes to use. The four different digital modes of operation are controlled by the data 2 and data 3 lines into the C-2000 interface board on the DSP exciter. If the paging data requires a different devi-ation, the C-2000 transmitter controller can change the mode without having to change the channel. This allows the DSP exciter to accommodate different paging format requirements without unkeying the transmitter to change channels. 7.5.1 Programming Example To set up the exciter for the proper digital deviation and offset programming, make up a table similar to the one shown below. Next, access Digital Mode Setup menu and select View Channel Frequencies submenu. Table 7-1 Deviation and Offset Programming Channel 1&9 2&10 3&11 4&12 5&13 6&14 7&15 8&16 Mode/Dev.A 4500 4500 4500 4500 4500 4500 4500 4500 Mode/Offset A 0 +400 -400 +300 0 -300 0 0 Mode/Dev.B 4800 4800 4800 4800 4800 4800 4800 4800 Mode/Offset B 0 +200 -200 +400 0 +400 -400 0 Mode/Dev.C 2400 4200 4200 2400 2400 4200 2400 4200 Mode/Offset C 0 0 0 0 0 0 0 0 Mode/Dev.D 4200 2400 4200 2400 2400 2400 4200 2400 Mode/Offset D 0 0 +400 -400 0 0 0 0 Note Initial release has setup similar to above table. Subsequent releases may have more programming variations ISC Technologies Document Number: 9110.00172 DSP Exciter Issue 1, Rev. N: 09/25/11 MAINTENANCE Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 7-2
Note When on-the-fly software is used with a QT-1000 interface board installed in the exciter, only the deviation and offset programming for mode D is available. References in the exciter menus pertaining to modes A, B, and C are blanked out. 7.5.1.1 Release 2.10 DSP Exciter The C-2000 transmitter controller detects a FLEX baud rate of 1600. When this condition is detected, the mode control lines to the DSP exciter change it to mode B. If the FLEX baud rate is not detected, the mode control lines are set for mode A. This requires that mode A deviation (and offset) be set for POCSAG (512, 1200 or 2400 baud), Golay, NEC and any other paging format other than FLEX requirements. Mode B deviation and offset must be set for FLEX. Mode C and D are not used. 7.6 16-Channel Operation With 16-channel capability, the on-the-fly digital mode programming is only programmable on 8 channels. When channels 1 through 8 are programmed for different modes, channels 9 through 16 follow the same mode programming respectively (i.e. channel 9 is the same as 1, channel 10 is the same as 2, etc.). Selecting additional channels (9 through 16) is achieved by the C-2000 controller pulling mode-1 line low to the C-2000 interface board. DSP Exciter ISC Technologies Document Number: 9110.00172 MAINTENANCE Issue 1, Rev. N: 09/25/11 Page: 7-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
7.7 On-The-Fly Interface Figure 7-1 On-The-Fly C2000 Control Lines to DSP Exciter ISC Technologies Document Number: 9110.00172 DSP Exciter Issue 1, Rev. N: 09/25/11 MAINTENANCE Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 7-2
Notes: A C-2000 interface board in the DSP exciter must be used with on-the-fly software All J1 pin connections shown on the above diagram are at the input to the C-2000 interface board in the DSP exciter Data 0 at the input of the C-2000 interface board controls Data 1 at its output Data 1 at the input of the C-2000 interface board controls Data 2 at its output Data 2 at the input of the C-2000 interface board controls Data 3 at its output Data 3 at the input of the C-2000 interface board controls Data 4 at its output Mode 0 at the input of the C-2000 interface board controls Mode sel 1 at its output Mode 1 at the input of the C-2000 interface board controls Mode sel 2 at its output Freq 0 at the input of the C-2000 interface board controls Ch select 1 at its output Freq 1 at the input of the C-2000 interface board controls Ch select 2 at its output Freq 2 at the input of the C-2000 interface board controls Ch select 3 at its output DSP Exciter ISC Technologies Document Number: 9110.00172 MAINTENANCE Issue 1, Rev. N: 09/25/11 Page: 7-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
Issue 1, Rev. N: 09/25/11 CHECKOUT AND TROUBLESHOOTING 8 CHECKOUT AND TROUBLESHOOTING 8.1 CHECKOUT The DSP exciter has two functions; it produces on-frequency RF and has a microprocessor to handle input from the PA and transmitter controller. Checkout involves verifying that RF is produced and unkeying occurs during a fault condition. 8.2 TROUBLESHOOTING The recommended troubleshooting level for the exciter is at the unit level. That is, if the exciter fails to provide the transmitter system with a usable, modulated RF-drive signal and all the exciter’s power, control, and signal inputs are normal, you should replace the exciter with a spare. ISC Technologies Document Number: 9110.00172 DSP Exciter Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 2-1
DSP Exciter ISC Technologies Document Number: 9110.00172 CHECKOUT AND TROUBLESHOOTING Issue 1, Rev. N: 09/25/11 Page: 8-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
Issue 1, Rev. N: 09/25/11 REMOVAL AND REINSTALLATION 9 REMOVAL AND REINSTALLATION Remove all input power from transmitter cabinet before performing these procedures. 9.1 Exciter/PA Control Chassis Refer to Figure 9-1, DSP Exciter Chassis Removal and Reinstallation , for a detailed drawing. Note Memory PROMs in the replacement exciter should be the same as in the original exciter unless the maintenance technician intends to modify exciter characteristics. Also, parameters, such as channel frequencies, may be stored in nonvolatile RAM. Ensure that the replacement exciter is programmed correctly. 9.1.1 Removal Procedure 1. Support exciter while removing the four screws from the front panel that secure it to the cabinet. Save screws for installation procedure. 2. Remove exciter from cabinet far enough to access back panel. 3. Disconnect connector J3 from connector P3 that is pigtailed off terminal board TB 1 (dc power input). 4. If a controller interface I/O panel is mounted on exciter back panel, remove I/O panel; leave all wires connected to I/O panel. 5. Tag all connectors attached to the exciter back panel. 6. Remove all connectors attached to the exciter back panel. Leave P3 connector/wiring assembly connected to terminal board TB1 for now. 7. Remove exciter. 8. Tag wires connected to terminal board TB1 on P3 connector/wiring assembly. 9. Disconnect tagged wires from terminal board TB1. Save P3 connector/wiring assem-bly for installation procedure. Procedure is complete. 9.1.2 Reinstallation Procedure Note A wideband DSP exciter that is installed in a GL-T8500 or GL-T8600 transmitter must have one rack unit of space between it and the power amplifier chassis. ISC Technologies Document Number: 9110.00172 DSP Exciter Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 9-1
1. Before installing exciter, connect wires on P3 connector/wiring assembly to terminal board TB 1 on exciter back panel. P3 connector/wiring assembly is saved from removal procedure. 2. Connect connectors on transmitter to exciter back panel. 3. If controller requires interface I/O panel, install external interface I/O board on exciter back panel (see Paragraph 9. 4). 4. Connect connector J3 to connector P3 that is pigtailed off of terminal board TB 1. 5. Locate connector P3 that is pigtailed off of terminal board TB 1. Disconnect connector P3 from connector J3. 6. Slide exciter into cabinet and secure with four screws saved from removal procedure. Procedure is complete. Perform setup, adjustment, or calibration procedures as required. 9.2 Exciter Cover These procedures must be performed with the exciter removed from the transmitter cabinet. Refer to Figure 9-2, DSP Exciter Cover Removal and Reinstallation throughout these procedures. 9.2.1 Removal Procedure 1. Remove two sem screws from sides of exciter cover. Save sem screws for installation procedure. 2. Raise front of cover and extract back of cover from channel in back panel extrusion. 3. Remove exciter cover. Procedure is complete. 9.2.2 Reinstallation Procedure 1. Insert exciter cover into channel on exciter back panel extrusion. 2. Lower cover so that fingerstock is behind exciter front panel. 3. While pressing down slightly on exciter cover: install two sem screws saved from re-moval procedure through sides of exciter cover. Procedure is complete. DSP Exciter ISC Technologies Document Number: 9110.00172 REMOVAL AND REINSTALLATION Issue 1, Rev. N: 09/25/11 Page: 9-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
Issue 1, Rev. N: 09/25/11 REMOVAL AND REINSTALLATION ISC Technologies Document Number: 9110.00172 DSP Exciter Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 9-2
v 0 1 7 1 . hg l Figure 9-2 DSP Exciter Cover Removal and Reinstallation DSP Exciter ISC Technologies Document Number: 9110.00172 REMOVAL AND REINSTALLATION Issue 1, Rev. N: 09/25/11 Page: 9-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
Issue 1, Rev. N: 09/25/11 REMOVAL AND REINSTALLATION 9.3 Exciter/Control Board These procedures must be performed with the exciter removed from the transmitter cabinet, and the exciter cover removed. Refer to Figure 9-3, DSP Exciter Control Board Removal and Reinstallation, throughout these procedures. 9.3.1 Removal Procedure Note Save all hardware for installation procedure. 1. Remove controller interface board (see Table Paragraph 9.4 ). 2. Remove VCO/RF amplifier board (see Table Paragraph 9.5 ). 3. Remove three kep nuts and three screws from regulators U1, U2, and U58. 4. Remove shoulder washer from regulator U58. 5. Remove two jam nuts and two lock washers from connectors J7 and J8. 6. Remove two jack socket screws attached to connector J6 through back panel. 7. Remove four sem screws from back panel and remove back panel from exciter chas- sis. Some exciters use three sem screws and one standoff. 8. Remove insulator between back panel and regulator U58. 9. Remove two jack socket screws attached to connector J3 through front panel. 10. Remove two studded standoffs through exciter/control board. 11. Remove nine sem screws that attach exciter/control board to exciter chassis, and re- move exciter/control board. Procedure is complete. 9.3.2 Reinstallation Procedure Note Use hardware saved from installation procedure. 1. Position exciter/control board onto exciter chassis and secure with nine sem screws. 2. Install two studded standoffs through exciter/control board. 3. Apply Vibra Tite or similar nonpermanent self-locking liquid adhesive to threads of the two jack socket screws to be used for connector J3. Apply only to top 1/4 inch of thread on each jack socket screw. 4. Install two jack socket screws into connector J3 through front panel. 5. Apply thermal compound as follows: between regulator U1 and back panel, between regulator U2 and back panel, between regulator U58 and insulator, and between insulator and back panel. ISC Technologies Document Number: 9110.00172 DSP Exciter Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 9-2
6. Install insulator between regulator U58 and back panel.
7. Position back panel on exciter chassis and secure with four sem screws. Some excit-ers use three sem screws and one standoff in the bottom right corner. 8. Apply Vibra Tite or similar nonpermanent self-locking liquid adhesive to threads of the two jack socket screws to be used for connector J6. Apply only to top 1/4 inch of thread on each jack socket screw. 9. Install two jack socket screws into connector J6 through back panel. 10. Install two lock washers and two jam nuts over connectors J7 and J8. 11. Install shoulder washer into regulator U58. 12. Install three kep nuts and three screws through regulators U1, U2, and U58. 13. Install VCO/RF amplifier board (see Table Paragraph 9.5 ). 14. Install controller interface board (see Table Paragraph 9.4 ). Procedure is complete. After exciter is installed in transmitter cabinet: perform setup procedure if necessary (refer to the system and menu manuals). DSP Exciter ISC Technologies Document Number: 9110.00172 REMOVAL AND REINSTALLATION Issue 1, Rev. N: 09/25/11 Page: 9-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
Issue 1, Rev. N: 09/25/11 REMOVAL AND REINSTALLATION v 0 1 7 0 . hg l Figure 9-3 DSP Exciter Control Board Removal and Reinstallation ISC Technologies Document Number: 9110.00172 DSP Exciter Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 9-2
9.4 Interface Board These procedures must be performed with the exciter removed from the transmitter cabinet (see Paragraph 9.1), and the exciter cover removed (see Paragraph 9.2). Refer to Figure 9- 4, DSP Exciter External Interface I/O Board Removal and Reinstallation, throughout the following procedures. 9.4.1 Removal Procedure 1. Remove jack socket screws (2 or 6) securing connector J4 (J1 and J2 not always used) to the rear panel of the exciter. Save jack socket screws for installation procedure. 2. Remove two sem screws securing interface board to standoffs. Save sem screws for installation procedure. 3. Grasp interface board at the center of connector P 1. Pull up on board with a firm ver-tical motion to disengage connector P1 from connector J1 on the exciter/control board. 4. Remove interface board. Procedure is complete. 9.4.2 Reinstallation Procedure 1. Position interface board into place by inserting connector J4 (and J1 and J2 if used) through openings in exciter rear panel. 2. Carefully align connector P1 on interface board with connector J1 on exciter/control board and engage. 3. Secure interface board to standoffs with two sem screws saved from removal proce-dure. 4. Apply Vibra Tite or similar nonpermanent self-locking liquid adhesive to threads of the six jack socket screws saved from removal procedure. Apply only to top 1/4 inch of thread on each jack socket screw. 5. Screw the six jack socket screws through holes on exciter rear panel at either sides of connectors J1, J4, and J2. Procedure is complete. After exciter is installed into transmitter cabinet, perform audio input adjustment procedure (see Section 7). 9.5 VCO/RF Amplifier Board These procedures must be performed with the exciter removed from the transmitter cabinet (see Paragraph 9.1), and the exciter cover removed (see Paragraph 9.2). Refer to Figure 9- 5, DSP Exciter Interface Board Removal and Reinstallation, throughout these procedures. DSP Exciter ISC Technologies Document Number: 9110.00172 REMOVAL AND REINSTALLATION Issue 1, Rev. N: 09/25/11 Page: 9-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
Issue 1, Rev. N: 09/25/11 REMOVAL AND REINSTALLATION 9.5.1 Removal Procedure 1. Remove jam nut and lock washer from connector J3 on rear of exciter. Save jam nut and lock washer for installation procedure. 2. Remove five sem screws securing VCO/RF amplifier board to standoffs on exciter. Save sem screws for installation procedure. 3. Grasp VCO/RF amplifier board near connector P4. Pull up on board with a short ver-tical motion to disengage connectors P4/P9/P10 from connectors J4/J9/J10 on exciter/ control board. 4. Remove VCO/RF amplifier board. Procedure is complete. 9.5.2 Reinstallation Procedure 1. Before installing VCO/RF amplifier board, verify that RF band includes desired transmitter operating frequencies (refer to Section 10). 2. Position VCO/RF amplifier board into place by inserting connector J3 through hole in rear of exciter. 3. Carefully align connectors P4/P9/P10 on VCO/RF amplifier board with connectors J4/J9/J10 on exciter/control board and engage. 4. Secure VCO/RF amplifier board to standoffs on exciter using five sem screws saved from removal procedure. 5. Install lockwasher and jam nut to connector J3 on rear of exciter using lockwasher and jam nut saved from removal procedure. Procedure is complete. After exciter is installed into transmitter cabinet, perform VCO2 adjustment procedure in Section 7. ISC Technologies Document Number: 9110.00172 DSP Exciter Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 9-9
v 0 3 4 1 . hg l Figure 9-4 DSP Exciter External Interface I/O Board Removal and Reinstallation DSP Exciter ISC Technologies Document Number: 9110.00172 REMOVAL AND REINSTALLATION Issue 1, Rev. N: 09/25/11 Page: 9-10 Copyright © 2011 ISC Technologies Print Date: 09/25/11
Issue 1, Rev. N: 09/25/11 REMOVAL AND REINSTALLATION v 0 3 4 2 . hg l Figure 9-5 DSP Exciter Interface Board Removal and Reinstallation ISC Technologies Document Number: 9110.00172 DSP Exciter Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 9-11
DSP Exciter ISC Technologies Document Number: 9110.00172 REMOVAL AND REINSTALLATION Issue 1, Rev. N: 09/25/11 Page: 9-12 Copyright © 2011 ISC Technologies Print Date: 09/25/11
Issue 1, Rev. N: 09/25/11 OPTIONS 10 OPTIONS 10.1 Exciter/PA Control with QT-1000 Interface The controller interface is the portion of exciter circuitry that connects the transmitter controller to the exciter. The controller interface dictates what kind of transmitter controller may operate the transmitter. The transmitter can be operated through one of several control-lers depending on the interface circuitry installed with the exciter. Two boards form this interface, the internal QT-1000 interface board and the external interface I/O board. Control commands from the transmitter controller are connected through the interface circuit. This circuit supplies remote control to the microcontroller unit (MCU) control circuit. The VT-100 VDT supplies local control. The MCU control circuit generates all control signals for the other circuits, and monitors their status. The MCU control circuit reports status back to the VT-100 VDT and the interface circuit, which supplies the status to the transmitter controller. 10.1.1 Reference Source The ten-MHz reference signal is provided by the controller via J8 on the exciter/control board. 10.1.2 Controller Interface Connector Functions Refer to Figure 10-1, Table 10-1, and Table 10-2 for a pin-by-pin description of signal functions. The controller interfaces with the transmitter through connectors J1, J2, and J5 and terminal board TB2 at the exciter back panel. J5 on the external I/O board connects to a standard RL-XX3 receiver, if installed. If a standard receiver is not installed, TB2 on the external I/O board connects to any generic receiver. TB2 also makes connections to optional configurable QT-1000 alarm inputs and switching outputs. J1 on the internal interface board connects directly to TXC connector J1, and interfaces all signals except alarms. Alarm signals, consisting of transmitter alarm, fault, and status signals, are supplied directly to the QT-1000 controller connector J2 though J2 on the internal interface board. 10.1.3 QT-1000 Interface Conversion Functions Many of the signals exchanged between the controller and the exciter originate with a format, voltage, or requirement incompatible with their destination. The QT-1000 interface performs any signal conversions necessary to provide compatibility between the controller and the exciter. The following text describes any signal conversions made by the controller interface. ISC Technologies Document Number: 9110.00172 DSP Exciter Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 10-1
ISC Technologies Document Number: 9110.00172 Issue 1, Rev. N: 09/25/11 10.1.3.1 Analog-Mode A/D Conversion The exciter DSP modulator circuit reads synchronized serial data for its analog mode input signal, but the QT-1000 controller provides an analog signal. The controller interface converts the analog to the appropriate data form for the DSP. The analog (FLAT AUDIO+,-) terminates across a balanced input circuit that also provides a level adjustment. The adjustment, when properly set by the AUDIO INPUT ADJUST pot through the exciter cover, provides analog to an A/D converter at the optimum zero-dBm level. The A/D converts the analog into serial data, which is applied to the DSP through a synchronous data link. A synchronous data link is characterized by an exchange of pulse streams for timing purposes. The A/D converter is clocked by a pulse generator circuit driven by the ten-MHz reference circuit. 10.1.3.2 FSK-Data-Bit Strapping The exciter DSP modulator circuit can read up to four bits for its digital FSK mode input signal, but the controller provides two active bits 1 and 2 (DATA1, DATA2). This allows transmitter operation in the two-level or four-level mode. 10.1.3.3 Channel-Select-Bit Strapping The exciter MCU control circuit reads three bits to determine the remotely selected channel, but the QT-1000 controller provides only bits 1 and 2 (CH SEL 1,2). As a result, the QT-1000 controller can command only four channels. The controller interface keeps bit 3 open (high). Table 10-2 defines the transmitter operating channel resulting from the channel select inputs. 10.1.3.4 Mode-Select-Bit Strapping The exciter MCU control circuit reads two bits to determine the remotely selected mode, but the QT-1000 controller provides only bit 1 (MODE CONTROL). As a result, the QT-1000 controller can command only two modes. The controller interface straps bit 2 to ground (low). Table 10-3 defines the transmitter operating mode resulting from the model select input. 10.1.3.5 Power Sample D/A Conversion The QT-1000 controller reads two 0-to-2.5-volt voltages for its forward and reflected power sample inputs, but these power values are stored as data in the exciter MCU control circuit. The controller interface converts the data to voltages of the appropriate range for the QT-1000 controller. Data from the MCU representing the forward and reflected powers is written into a dual D/A converter. The D/A converts the data into two proportional dc voltages ranging from 0 volt to 2.5 volts (FWD PWR SAMPLE, REF PWR SAMPLE), which are applied to the QT-1000 controller. Control logic gates ensure that data is written to the proper half of the D/A converter. DSP Exciter OPTIONS Page: 10-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
Issue 1, Rev. N: 09/25/11 OPTIONS Table 10-1 Interface Board Connector J4 (QT-1000) J4-X signal/description J4-X signal/description 1 FWD PWR SAMPLE, input from PA 14 AUDIO INPUT +, input from re- ceiver or tx controller 2 AUDIO INPUT -, common 15 REF PWR SAMPLE, input from PA 3 TX GND 16 TONE DECODER OUTPUT, logic output to tx controller 4 KEY IN, input from tx controller 17 DATA 1, digital data input from tx controller 5 DATA 2, digital data input from tx controller 18 DATA 3, digital data input from tx controller 6 CH SELECT 3, digital command input from tx controller 19 MODE SELECT 1, digital com- mand input from tx controller 7 MODE SELECT 2, digital com- mand input from tx controller 20 LOW POWER MODE, logic input from PA 8 FAULT ALARM, digital output to tx controller 21 VSWR ALARM, logic output to tx controller 9 DATA4/CLK, input from tx con- troller 22 CH SELECT 1, logic input from tx controller 10 CH SELECT 2, logic input from tx controller 23 MOD IND, logic output to tx con- troller 11 LOW POWER ALARM, output to tx controller 24 TEMP ALARM, logic output to tx controller 12 SHUTDOWN ALARM, output to tx controller 25 RF INPUT ALARM, logic output to tx controller 13 not used -- -- ISC Technologies Document Number: 9110.00172 DSP Exciter Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 10-2
ISC Technologies Document Number: 9110.00172 Issue 1, Rev. N: 09/25/11 Table 10-2 Receiver Connector J5 Pin Functions (QT-1000 with external I/O board) J5-X function J5-X function 1 no connection 9 no connection 2 standard receiver audio input for interface, 2 Vp-p, nominal 10 no connection 3 no connection 11 return for standard receiver audio 4 no connection 12 standard receiver RSSI input for interface, 0.5-6.0 Vdc 5 no connection 13 no connection 6 standard receiver ground for inter- face 14 standard receiver-fault alarm input for interface, LO=OK 7 no connection 15 no connection 8 standard receiver squelch output for interface, HI=unsquelched Table 10-3 Remote Select Input vs. Channel (QT-1000) ch sel 1 J1-5 ch sel 2 J1-24 ch sel 3 selecte d channel command open (HI) command open (HI) open (HI) 1 command ground (LO) command open (HI) open (HI) 2 command open (HI) command ground (LO) open (HI) 3 command ground (LO) command ground (LO) open (HI) 4 DSP Exciter OPTIONS Page: 10-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
Table 10-4 Remote Select Input vs. Mode (QT-1000) mode sel 1 mode sel 2 J1-25 J2-1 selected mode command ground (LO) ground (LO) analog command open (HI) ground (LO) 2-level command open (HI) command open (HI) 4-level Note Not all transmitters can do all the modes. 10.2 Exciter/PA Control with Standard Interface The following major paragraphs describe the operation of the major items within the standard interface. Detailed figures are referenced, as required. The controller interface is the portion of exciter circuitry that connects the transmitter controller to the exciter. The controller interface dictates what kind of transmitter controller may operate the transmitter. The transmitter can be operated through one of several control-lers depending on the interface circuitry installed at the exciter. The remainder of section 10.2 describes standard controller interface circuitry. Two boards form this interface, the internal standard interface board and the external exciter standard interface I/O board. Control commands from the transmitter controller are connected through the interface circuit. This circuit supplies remote control to the microcontroller unit (MCU) control circuit. The VT-100 VDT supplies local control. The MCU control circuit generates all control signals for the other circuits, and monitors their status. The MCU control circuit reports status back to the VT-100 VDT and the interface circuit, which supplies the status to the transmitter controller. 10.2.1 Reference Source The ten-MHz reference signal is provided by the controller via J8 on the exciter/control board. All other inputs and outputs, except for RF output, are routed through the standard interface board. ISC Technologies Document Number: 9110.00172 DSP Exciter Issue 1, Rev. N: 09/25/11 OPTIONS Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 10-2
ISC Technologies Document Number: 9110.00172 Issue 1, Rev. N: 09/25/11 10.2.2 Controller Interface Connector Functions Refer to Table 10-1, Interface Board Connector J4 (QT-1000) for a pin-by-pin description of signal functions. The controller interfaces with the transmitter through connector J4 and terminal board TB2 at the exciter back panel. TB2 also makes connections to optional configurable alarm inputs and switching outputs. 10.2.3 Standard Interface Conversion Functions Many of the signals exchanged between the controller and the exciter originate with a format, voltage, or requirement incompatible with their destination. The standard interface performs any signal conversions necessary to provide compatibility between the controller and the exciter. The following text describes any signal conversions made by the controller interface. 10.2.3.1 Analog-Mode A/D Conversion (No Analog for 138.0-174.0 MHZ & 406.0-470.0 MHz) The exciter DSP modulator circuit reads synchronized serial data for its analog mode input signal, but the transmitter controller provides an analog signal. The controller interface converts the analog to the appropriate data form for the DSP. The analog (FLAT AUDIO +,-) terminates across a balanced input circuit that also provides a level adjustment. The adjustment, when properly set by the AUDIO INPUT ADJUST pot through the exciter cover, provides analog to an A/D converter at the optimum zero-dBm level. The A/D converts the analog into serial data, which is applied to the DSP through a synchronous data link. A synchronous data link is characterized by an exchange of pulse streams for timing purposes. The A/D converter is clocked by a pulse generator circuit driven by the exciter’s ten-MHz reference circuit. 10.2.3.2 FSK-Data-Bit Strapping The exciter DSP modulator circuit can read up to four bits for its digital FSK mode input signal, but the controller provides two active bits 1 and 2 (DATA1, DATA2). This allows transmitter operation in the two-level or four-level mode. 10.2.3.3 Channel-Select-Bit Strapping The exciter MCU control circuit reads three bits to determine the remotely selected channel, and the transmitter controller provides bits 1, 2, and 3 (CH SEL 1,2,3). As a result, the transmitter controller can command all eight of the possible channels. Table 10-3, Remote Select Input vs. Channel (QT-1000), defines the transmitter operating channel resulting from the channel select inputs. 10.2.3.4 Mode-Select-Bit Strapping The exciter MCU control circuit reads two bits to determine the remotely selected mode, but the transmitter controller provides only bit 1 (MODE CONTROL). As a result, the transmitter controller can command three of the transmitter’s four possible modes. Table 10-4, Remote Select Input vs. Mode (QT-1000), defines the transmitter operating mode DSP Exciter OPTIONS Page: 10-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
resulting from the model select input.
10.2.3.5 Power Sample D/A Conversion The transmitter controller reads two 0-to-2.5-volt voltages for its forward and reflected power sample inputs, but these power values are stored as data within the exciter’s MCU control circuit. The controller interface converts the data to voltages of the appropriate range for the transmitter controller. Data from the MCU representing the forward and reflected powers is written into a dual D/A converter. The D/A converts the data into two proportional dc voltages ranging from 0 volt to 2.5 volts (FWD PWR SAMPLE, REF PWR SAMPLE), which are applied to the transmitter controller. Control logic gates ensure that data is written to the proper half of the D/A converter. Table 10-5 Interface Board Connector J4 (Standard) J4-X signal/description J4-X signal/description 1 FWD PWR SAMPLE, input from PA 14 AUDIO INPUT -, input from re- ceiver or tx controller (No Analog for 138.0-174.0 MHZ & 406.0-470.0 MHz) 2 AUDIO INPUT +, common (No Analog for 138.0-174.0 MHZ & 406.0-470.0 MHz) 15 REF PWR SAMPLE, input from PA 3 TX GND 16 TONE DECODER OUTPUT, logic output to tx controller 4 KEY IN, input from tx controller 17 DATA 1, digital data input from tx controller 5 DATA 2, digital data input from tx controller 18 DATA 3, digital data input from tx controller 6 CH SELECT 3, digital command input from tx controller 19 MODE SELECT 1, digital com- mand input from tx controller 7 MODE SELECT 2, digital com- mand input from tx controller 20 LOW POWER MODE, logic input from PA 8 FAULT ALARM, digital output to tx controller 21 VSWR ALARM, logic output to tx controller 9 DATA4/CLK, input from tx con- troller 22 CH SELECT 1, logic input from tx controller 10 CH SELECT 2, logic input from tx controller 23 MOD IND, logic output to tx controller 11 LOW POWER ALARM, output to tx controller 24 TEMP ALARM, logic output to tx controller 12 SHUTDOWN ALARM, output to tx controller 25 RF INPUT ALARM, logic out- put to tx controller 13 not used -- -- ISC Technologies Document Number: 9110.00172 DSP Exciter Issue 1, Rev. N: 09/25/11 OPTIONS Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 10-2
ISC Technologies Document Number: 9110.00172 Issue 1, Rev. N: 09/25/11 Table 10-6 Remote Select Input vs. Channel (standard) ch sel 1 ch sel 2 ch sel 3 J4-22 J4-10 J4-6 selected channel command open (HI) command open (HI) open (HI) 1 command ground (LO) command open (HI) open (HI) 2 command open (HI) command ground (LO) open (HI) 3 command ground (LO) command ground (LO) open (HI) 4 command open (HI) command open (HI) command ground (LO) 5 command ground (LO) command open (HI) command ground (LO) 6 command open (HI) command ground (LO) command ground (LO) 7 command ground (LO) command ground (LO) command ground (LO) 8 Table 10-7 Remote Select Input vs. Mode (standard) mode sel 1 mode sel 2 J4-19 J4-7 selected mode command ground (LO) ground (LO) analog command open (HI) ground (LO) 2-level command open (HI) command open (HI) 4-level Note DSP Exciter OPTIONS Page: 10-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
Not all transmitters can do all the modes.
10.3 Exciter/PA Control with I20 Interface The following major paragraphs describe the operation of the major items within the I20 interface. Detailed figures are referenced, as required. The controller interface is the portion of exciter circuitry that connects the transmitter controller to the exciter. The controller interface dictates what kind of transmitter controller may operate the transmitter. The transmitter can be operated through one of several control-lers depending on the interface circuitry installed at the exciter. The remainder of section 10.3 describes I20 controller interface circuitry. Two boards form this interface, the internal I20 interface board and the external I20 interface I/O board. Control commands from the transmitter controller are connected through the interface circuit. This circuit supplies remote control to the microcontroller unit (MCU) control circuit. The VT-100 VDT supplies local control. The MCU control circuit generates all control signals for the other circuits, and monitors their status. The MCU control circuit reports status back to the VT-100 VDT and the interface circuit, which supplies the status to the transmitter controller. 10.3.1 Reference Source The ten-MHz reference signal is provided by the controller via J8 on the exciter/control board. 10.3.2 Controller Interface Connector Functions Refer to Table 10-8 and Table 10-9 for a pin-by-pin description of signal functions. The exciter interfaces with the transmitter through connector J2 and the controller through J1. 10.3.3 I20 Interface Conversion Functions Many of the signals exchanged between the controller and the exciter originate with a format, voltage, or requirement incompatible with their destination. The I20 interface performs any signal conversions necessary to provide compatibility between the controller and the exciter. The following text describes any signal conversions made by the controller interface. 10.3.3.1 Analog-Mode A/D Conversion The exciter DSP modulator circuit reads synchronized serial data for its analog mode input signal, but the transmitter controller provides an analog signal. The controller interface converts the analog to the appropriate data form for the DSP. The analog (FLAT AUDIO +,-) terminates across a balanced input circuit that also provides a level adjustment. The adjustment, when properly set by the AUDIO INPUT ADJUST pot through the exciter cover, provides analog to an A/D converter at the optimum zero-dBm level. The A/D converts the analog into serial data, which is applied to the DSP through a synchronous data ISC Technologies Document Number: 9110.00172 DSP Exciter Issue 1, Rev. N: 09/25/11 OPTIONS Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 10-2
ISC Technologies Document Number: 9110.00172 Issue 1, Rev. N: 09/25/11 link. A synchronous data link is characterized by an exchange of pulse streams for timing purposes. The A/D converter is clocked by a pulse generator circuit driven by the ten-MHz reference circuit. 10.3.3.2 FSK-Data-Bit Strapping The exciter DSP modulator circuit can read up to four bits for its digital FSK mode input signal, but the controller provides two active bits 1 and 2 (DATA1, DATA2). This allows transmitter operation in the two-level or four-level mode. 10.3.3.3 Channel-Select-Bit Strapping The exciter MCU control circuit reads three bits to determine the remotely selected channel, and the transmitter controller provides bits 1, 2, and 3 (CH SEL 1,2,3). As a result, the transmitter controller can command all eight of the possible channels. Table 10-3 defines the transmitter operating channel resulting from the channel select inputs. 10.3.3.4 Mode-Select-Bit Strapping The exciter MCU control circuit reads two bits to determine the remotely selected mode, and the transmitter controller provides two bits (MODE SELECT 1, MODE SELECT 2). As a result, the transmitter controller can command three of the transmitter’s four possible modes. Table 10-4 defines the transmitter operating mode resulting from the model select input. 10.3.3.5 Power Sample D/A Conversion The transmitter controller reads two 0-to-2.5-volt voltages for its forward and reflected power sample inputs, but these power values are stored as data within the exciter’s MCU control circuit. The controller interface converts the data to voltages of the appropriate range for the transmitter controller. Data from the MCU representing the forward and reflected powers is written into a dual D/A converter. The D/A converts the data into two proportional dc voltages ranging from 0 volt to 2.5 volts (FWD PWR SAMPLE, REF PWR SAMPLE), which are applied to the transmitter controller. Control logic gates ensure that data is written to the proper half of the D/A converter. Table 10-8 Interface Board Connector J1 J1-X signal/description J1-X signal/description 1 CHASSIS 20 CLOCK- 2 CLOCK+ 21 DATA0- 3 DATA0+ 22 DATA1- 4 DATA1+ 23 DATA2- 5 DATA2+ 24 DATA3- DSP Exciter OPTIONS Page: 10-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
Table 10-8 Interface Board Connector J1 (continued) J1-X signal/description J1-X signal/description 6 DATA3+ 25 GND 7 FREQ0 26 FREQ1 8 FREQ2 27 MODE 0 9 MODE 1 28 MODE/AUX 10 ANALOG+ 29 ANALOG- 11 GND 30 GND 12 RxD- 31 RxD+ 13 TxD- 32 TxD+ 14 KEY- 33 KEY+ 15 DIG OUT 6 34 DIG OUT 7 16 DIG OUT 4 35 DIG OUT 5 17 DIG OUT 2 36 DIG OUT 3 18 DIG OUT 0 37 DIG OUT 1 19 _RESET Table 10-9 Interface Board Connector J2 J2-X signal/description J2-X signal/description 1 not used 8 GND 2 TxD+ 9 TxD- 3 KEY+ 10 KEY- 4 RxD+ 11 RxD- 5 DATA0+ 12 DATA0- 6 CLOCK+ 13 CLOCK- 7 DATA1+ 14 DATA1- ISC Technologies Document Number: 9110.00172 DSP Exciter Issue 1, Rev. N: 09/25/11 OPTIONS Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 10-2
ISC Technologies Document Number: 9110.00172 Issue 1, Rev. N: 09/25/11 Table 10-10 Remote Select Input vs. Channel (I20) ch sel 1 ch sel 2 ch sel 3 ch sel 4 J1-7 J1-26 J1-8 J1-9 selected channel command open (HI) command open (HI) open (HI) open (HI) 1 command ground (LO) command open (HI) open (HI) open (HI) 2 command open (HI) command ground (LO) open (HI) open (HI) 3 command ground (LO) command ground (LO) open (HI) open (HI) 4 command open (HI) command open (HI) command ground (LO) open (HI) 5 command ground (LO) command open (HI) command ground (LO) open (HI) 6 command open (HI) command ground (LO) command ground (LO) open (HI) 7 command ground (LO) command ground (LO) command ground (LO) open (HI) 8 command open (HI) command open (HI) open (HI) command ground (LO) 9 command ground (LO) command open (HI) open (HI) command ground (LO) 10 command open (HI) command ground (LO) open (HI) command ground (LO) 11 command ground (LO) command ground (LO) open (HI) command ground (LO) 12 command open (HI) command open (HI) command ground (LO) command ground (LO) 13 command ground (LO) command open (HI) command ground (LO) command ground (LO) 14 DSP Exciter OPTIONS Page: 10-2 Copyright © 2011 ISC Technologies Print Date: 09/25/11
command open (HI) command ground (LO) command ground (LO) command ground (LO) 15
Issue 1, Rev. N: 09/25/11 OPTIONS Table 10-10 Remote Select Input vs. Channel (I20) (continued) ch sel 1 ch sel 2 ch sel 3 ch sel 4 J1-7 J1-26 J1-8 J1-9 selected channel command ground (LO) command ground (LO) command ground (LO) command ground (LO) 16 Table 10-11 Remote Select Input vs. Mode (I20) mode sel 1 J1-27 selected mode command ground (LO) analog command open (HI) digital ISC Technologies Document Number: 9110.00172 DSP Exciter Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 10-2
Issue 1, Rev. N: 09/25/11 List of Referenced Graphic Files List of Referenced Graphic Files /pics/v0077.hgl 6-13 /pics/v0079.hgl 5-2 /pics/v0081.hgl 6-12 /pics/v0083.hgl 6-6 /pics/v0123.hgl 6-2 /pics/v0151.hgl 9-3 /pics/v0170.hgl 9-7 /pics/v0171.hgl 9-4 /pics/v0341.hgl 9-10 /pics/v0342.hgl 9-11 /pics/v0345l.hgl 6-10 /pics/v0345r. hgl 6-11 /pics/v0854.hgl 7-5 s /pics/v0164.hgl 4-5 /pics/v0250.hgl 1-2 /pics/v0251.hgl 3-5 /pics/v0343.hgl 3-3 /pics/v0344.hgl 3-4 ISC Technologies Document Number: 9110.00172 DSP Exciter c Print Date: 09/25/11 Copyright © 2011 ISC Technologies Page: 1

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