Glenayre GL-T8541 User manual

Copyright © 1997 Glenayre
GL-T8541 PA 09/10/99
Specifications subject to change without notice
Copyright © 1997 Glenayre
All rights reserved. No part of this work may be reproduced or copied in any form or by
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taping, or information-retrieval system -- without written permission of Glenayre.
GL-T8541 Power Amplifier
USER MANUAL
PN 9110.01002
REV A

GL-T8541 PA Glenayre Document Number: 9110.01002
Document Change Record 09/10/99
Copyright © 1997 Glenayre
Document Change Record
Issue: Revision A
Date: 10/29/97
Changes: none, original

Glenayre Document Number: 9110.01002 GL-T8541 PA
09/10/99 Table of Contents
t8541p1.toc
Copyright © 1997 Glenayre Page: i
Table of Contents
1 GENERAL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
1.1 Manual Scope . . . . . . . . . . . . . . . . . . . . . . . . 1-1
1.2 Applicable Documents. . . . . . . . . . . . . . . . . . . . . 1-1
1.3 About Glenayre . . . . . . . . . . . . . . . . . . . . . . . 1-2
1.3.1 Product Warranty Information . . . . . . . . . . . . . . . . . . .1-2
1.3.2 Service Warranty Information . . . . . . . . . . . . . . . . . . .1-2
2 SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
2.1 General. . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
2.2 GL-T8541 PA Specifications . . . . . . . . . . . . . . . . . . 2-1
3 DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
3.1 General. . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
3.1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1
3.2 Physical Description. . . . . . . . . . . . . . . . . . . . . . 3-1
3.2.1 Electrical Connectors . . . . . . . . . . . . . . . . . . . . . . . .3-1
3.2.2 Chassis Cooling . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1
3.2.3 PA Front. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-2
3.2.4 PA Rear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-2
3.3 Conceptual Description . . . . . . . . . . . . . . . . . . . . 3-2
3.4 PA Module Interconnection. . . . . . . . . . . . . . . . . . . 3-5
3.4.1 PA Module Dc, Signal, and Control Wiring . . . . . . . . . . . .3-5
3.4.1.1 The Metering Board Location. . . . . . . . . . . . . .3-5
3.4.2 Isolator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-6
4 INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
4.1 Installation . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
4.1.1 Precautions and Hazards . . . . . . . . . . . . . . . . . . . . . .4-1
4.1.2 Test Equipment and Tools Required . . . . . . . . . . . . . . . .4-1
4.1.3 Component and Adjustment Locations . . . . . . . . . . . . . . .4-1
4.1.4 Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-2
4.1.5 Power Requirement . . . . . . . . . . . . . . . . . . . . . . . . .4-2
4.1.6 PA Module External Connectors . . . . . . . . . . . . . . . . . .4-2
5 OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
5.1 General. . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
5.2 Controls and Indicators . . . . . . . . . . . . . . . . . . . . 5-1
5.3 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
5.3.1 PA On and Off Control . . . . . . . . . . . . . . . . . . . . . . .5-1

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5.3.2 Turn Fan On and Off . . . . . . . . . . . . . . . . . . . . . . . . 5-1
5.3.3 Key and Unkey PA . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
6 THEORY OF OPERATION. . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
6.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
6.1.1 Adding The Optional Isolator . . . . . . . . . . . . . . . . . . . 6-2
6.2 Driver Board . . . . . . . . . . . . . . . . . . . . . . . . 6-2
6.2.1 Q1 Bias and Idle Current Adjustment . . . . . . . . . . . . . . . 6-3
6.2.2 Q2 Bias and Idle Current Adjustment . . . . . . . . . . . . . . . 6-3
6.3 The 1 to 3 Splitter Board . . . . . . . . . . . . . . . . . . . 6-4
6.4 PA Board . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
6.4.1 PA Bias and Idle Current Adjustment . . . . . . . . . . . . . . . 6-5
6.5 3 to 1 Combiner Board . . . . . . . . . . . . . . . . . . . . 6-6
6.5.1 The 3 to 1 Combiner . . . . . . . . . . . . . . . . . . . . . . . . 6-6
6.5.2 Low-Pass Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
6.5.3 Directional Coupler. . . . . . . . . . . . . . . . . . . . . . . . . 6-6
6.6 PA Module Overall RF Flow . . . . . . . . . . . . . . . . . . 6-8
6.7 Metering Board . . . . . . . . . . . . . . . . . . . . . . . 6-9
6.7.1 Temperature Monitoring Circuit . . . . . . . . . . . . . . . . . . 6-9
6.7.2 Metering Board to Combiner Board to Amplifier Board Interface6-10
6.7.3 Fan Power. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-11
6.7.4 Metering Board Fuses . . . . . . . . . . . . . . . . . . . . . . 6-11
6.7.5 Metering Board Regulators and Test Points . . . . . . . . . . . 6-12
6.7.6 The Analog Signal Multiplexers . . . . . . . . . . . . . . . . . 6-13
6.7.7 PA Current Monitoring Circuit . . . . . . . . . . . . . . . . . . 6-16
6.7.8 AGC Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-17
7 CHECKOUT AND MAINTENANCE . . . . . . . . . . . . . . . . . . . . . 7-1
7.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
7.1.1 Test Equipment and Tools Required . . . . . . . . . . . . . . . . 7-1
7.2 Maintenance For Cooling Fans . . . . . . . . . . . . . . . . . 7-1
7.3 Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . 7-2
7.4 Mechanical Integrity . . . . . . . . . . . . . . . . . . . . . 7-2
7.5 Input Voltage Check . . . . . . . . . . . . . . . . . . . . . 7-2
7.5.1 Metering Board Regulators. . . . . . . . . . . . . . . . . . . . . 7-2
7.6 Operational Tests . . . . . . . . . . . . . . . . . . . . . . 7-2
7.6.1 PA Fan and Air Flow Check . . . . . . . . . . . . . . . . . . . . 7-3
7.6.2 PA RF Output Test . . . . . . . . . . . . . . . . . . . . . . . . . 7-3

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7.6.3 Calibrating The RF Output of the PA. . . . . . . . . . . . . . . .7-4
7.6.4 Testing the Antenna and its RF Feedline . . . . . . . . . . . . . .7-5
7.6.5 Checking Isolator Loss . . . . . . . . . . . . . . . . . . . . . . .7-6
7.6.5.1 Checking Isolation of Isolator. . . . . . . . . . . . . .7-7
7.7 Setting PA Module Bias and Idle Current . . . . . . . . . . . . . 7-8
7.7.1 Checking Bias Settings . . . . . . . . . . . . . . . . . . . . . . .7-8
7.7.2 Checking Driver Q1 Bias Setting . . . . . . . . . . . . . . . . . .7-8
7.7.3 Setting PA Board RF Transistor Bias. . . . . . . . . . . . . . . .7-9
7.7.4 Setting Driver Board RF Transistor Bias . . . . . . . . . . . . . .7-9
7.8 Resume Paging Operation . . . . . . . . . . . . . . . . . . .7-12
7.9 Maintenance Log . . . . . . . . . . . . . . . . . . . . . . .7-12
7.10 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . .7-12
7.10.1 Troubleshooting Chart . . . . . . . . . . . . . . . . . . . . . . 7-12
7.11 Advanced Troubleshooting . . . . . . . . . . . . . . . . . . .7-15
7.11.1 Checking PA Module Supply Voltage . . . . . . . . . . . . . . 7-15
7.11.1.1 Open Transistor or Blown Fuse. . . . . . . . . . . . 7-15
7.11.1.2 Measuring PA Module Voltages . . . . . . . . . . . 7-15
7.11.2 Driver Board Troubleshooting . . . . . . . . . . . . . . . . . . 7-16
7.11.2.1 Checking the Exciter Output . . . . . . . . . . . . . 7-16
7.11.2.2 Checking Driver Board Q1 . . . . . . . . . . . . . . 7-17
7.11.2.3 Driver Board Output Test. . . . . . . . . . . . . . . 7-19
7.11.3 PA Board Troubleshooting . . . . . . . . . . . . . . . . . . . . 7-21
7.11.3.1 Finding Bad PA board . . . . . . . . . . . . . . . . 7-21
8 REMOVAL AND REINSTALLATION. . . . . . . . . . . . . . . . . . . . . 8-1
8.1 Fan Removal . . . . . . . . . . . . . . . . . . . . . . . . 8-1
8.2 Transmitter Chassis Removal . . . . . . . . . . . . . . . . . . 8-1
8.3 Top Cover Removal. . . . . . . . . . . . . . . . . . . . . . 8-2
8.4 Driver Board. . . . . . . . . . . . . . . . . . . . . . . . . 8-2
8.4.1 Removal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-2
8.4.2 Reinstallation . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-2
8.5 Splitter Board . . . . . . . . . . . . . . . . . . . . . . . . 8-3
8.5.1 Removal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-3
8.5.2 Reinstallation . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-3
8.6 PA Board . . . . . . . . . . . . . . . . . . . . . . . . . . 8-4
8.6.1 Removal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-4
8.6.2 Reinstallation . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-4

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8.7 Combiner Board . . . . . . . . . . . . . . . . . . . . . . . 8-5
8.7.1 Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5
8.7.2 Reinstallation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5
8.8 Metering Board . . . . . . . . . . . . . . . . . . . . . . . 8-6
8.8.1 Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-6
8.8.2 Reinstallation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-6

Glenayre Document Number: 9110.01002 GL-T8541 PA
09/10/99 List of Figures
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Copyright © 1997 Glenayre Page: v
List of Figures
Figure 3-1 GL-T8541 PA with DSP Exciter . . . . . . . . . . . . . . . . . . . . . 3-3
Figure 3-2 GL-T8541 PA Module Front and Top View (no cover) . . . . . . . . . 3-4
Figure 3-3 PA Module Circuit Board Connecting Copper Jumper Straps . . . . . . 3-6
Figure 4-1 PA Cabling (external). . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
Figure 5-1 GL-T8541 Front View with DSP Exciter. . . . . . . . . . . . . . . . . 5-2
Figure 6-1 GL-T8541 PA Module RF Flow Block Diagram. . . . . . . . . . . . . 6-1
Figure 6-2 Block Diagram Driver and 1 to 3 Splitter Boards . . . . . . . . . . . . 6-3
Figure 6-3 PA Board Block Diagram. . . . . . . . . . . . . . . . . . . . . . . . . 6-5
Figure 6-4 The 3 to 1 Combiner Board Block Diagram . . . . . . . . . . . . . . . 6-7
Figure 6-5 PA Module Overall RF Flow . . . . . . . . . . . . . . . . . . . . . . . 6-8
Figure 6-6 Metering Board Block Diagram . . . . . . . . . . . . . . . . . . . . .6-14
Figure 6-7 Metering Board Fuses, Test Points, and Jumpers (2000.00601) . . . . .6-15
Figure 6-8 Metering Board Simplified Current Monitoring Circuits. . . . . . . . .6-16
Figure 6-9 Metering Board Simplified AGC Circuit . . . . . . . . . . . . . . . . .6-17
Figure 6-10 Metering Board Schematic, page 1 or 2 (2000.00601) . . . . . . . . . .6-18
Figure 6-11 Metering Board Schematic, page 2 of 2 (2000.00601) . . . . . . . . . .6-19
Figure 6-12 Driver Board Assembly, Top View (2000.00050) . . . . . . . . . . . .6-20
Figure 6-13 Driver Board Schematic (2000.00050) . . . . . . . . . . . . . . . . . .6-21
Figure 6-14 3 to 1 Splitter Assembly, Top View (2000.00145) . . . . . . . . . . . .6-22
Figure 6-15 3 to 1 Splitter Schematic (2000.00145). . . . . . . . . . . . . . . . . .6-23
Figure 6-16 120 Watt PA Board Assembly, Top View (2000.00027). . . . . . . . .6-24
Figure 6-17 120 Watt PA Board Schematic (2000.00027) . . . . . . . . . . . . . .6-25
Figure 6-18 3 to 1 Combiner Assembly, Top View (2000.00106) . . . . . . . . . .6-26
Figure 6-19 3 to 1 Combiner Schematic (2000.00106) . . . . . . . . . . . . . . . .6-27
Figure 7-1 Chassis Back View . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-4
Figure 7-2 Power Amplifier RF Output Power Calibration Setup . . . . . . . . . . 7-4
Figure 7-3 Antenna System Test Setup. . . . . . . . . . . . . . . . . . . . . . . . 7-5
Figure 7-4 Isolator loss Test Setup . . . . . . . . . . . . . . . . . . . . . . . . . . 7-6
Figure 7-5 Test Setup to Measure Isolation of the Isolator. . . . . . . . . . . . . . 7-7
Figure 7-6 Driver Board (left) and PA BOARD (right) Layouts. . . . . . . . . . .7-11
Figure 7-7 Exciter Output Test Setup. . . . . . . . . . . . . . . . . . . . . . . . .7-16
Figure 7-8 Driver Board Q1 Test Setup Block Diagram . . . . . . . . . . . . . . .7-17
Figure 7-9 Driver Board Q1 Test Setup . . . . . . . . . . . . . . . . . . . . . . .7-18
Figure 7-10 Driver Board Output Test Setup Block Diagram . . . . . . . . . . . . .7-19
Figure 7-11 Driver Board RF Output Test Setup . . . . . . . . . . . . . . . . . . .7-20

GL-T8541 PA Glenayre Document Number: 9110.01002
List of Figures 09/10/99
Page: vi Copyright © 1997 Glenayre
Figure 7-12 120 Watt PA Board Showing RF Transistor Gate and Drain Pads. . . . 7-22
Figure 8-1 Fan Panel Assembly (exploded) . . . . . . . . . . . . . . . . . . . . . 8-7
Figure 8-2 Top Cover Details . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-8
Figure 8-3 Driver Board Mounting Diagram. . . . . . . . . . . . . . . . . . . . . 8-9
Figure 8-4 3 to 1 Splitter Board Mounting Diagram. . . . . . . . . . . . . . . . . 8-10
Figure 8-5 PA Board Mounting Diagram . . . . . . . . . . . . . . . . . . . . . . 8-11
Figure 8-6 3 to 1 Combiner Board Mounting Diagram . . . . . . . . . . . . . . . 8-12
Figure 8-7 Metering Board Mounting Diagram . . . . . . . . . . . . . . . . . . . 8-13

Glenayre Document Number: 9110.01002 GL-T8541 PA
09/10/99 List of Tables
t8541p1.lot
Copyright © 1997 Glenayre Page: vii
List of Tables
Table 1-1 Applicable Documents . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Table 1-2 Schematic Numbers. . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Table 2-1 PA Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Table 3-1 Power Amplifier Assemblies . . . . . . . . . . . . . . . . . . . . . . . 3-2
Table 3-2 Metering Board (J1) to Combiner Board (J8) Connector Pinout . . . . . 3-5
Table 6-1 GL-T8541 PA Optional Isolator RF Power Output. . . . . . . . . . . . 6-2
Table 6-2 Metering Board to Combiner Board Interface . . . . . . . . . . . . . .6-10
Table 6-3 Power Amplifier Metering Board Fuses . . . . . . . . . . . . . . . . .6-11
Table 6-4 Metering Board Test Points. . . . . . . . . . . . . . . . . . . . . . . .6-12
Table 6-5 Metering Board Multiplex Chip Inputs . . . . . . . . . . . . . . . . . .6-13
Table 7-1 Relationship of VSWR to Fwd and Ref Power. . . . . . . . . . . . . . 7-5
Table 7-2 GL-T8541 PA Optional Isolator RF Power Output. . . . . . . . . . . . 7-6
Table 7-3 PA Module Faults. . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-13

GL-T8541 PA Glenayre Document Number: 9110.01002
List of Tables 09/10/99
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