Nova PR400 Operating and maintenance manual

MOTOROLA and The Stylized M logo are trademarks of Motorola, Inc.
All other product or service names are the property of their respective owners.
© 2005 Motorola, Inc. All rights reserved. Printed in U.S.A.
*6881096C25*
6881096C25-B
PR400™
Commercial Series
Portable Radio
Detailed Service Manual

PR400 Portable Radio
Detailed Service Manual
VHF 136-162 MHz
VHF 146-174 MHz
UHF 403-440 MHz
UHF 438-470 MHz
UHF 465-495 MHz
Motorola, Inc.
1301 E. Algonquin Road
Schaumburg, IL 60196 6881096C25-B

ii
Foreword
This manual is intended for use by service technicians familiar with portable two-way radios. It contains
service information required for the equipment described and is current as of the printing date. Changes which
occur after the printing date may be incorporated by a complete Manual revision or alternatively as additions
Product Safety and RF Exposure Compliance
ATTENTION!
This radio is restricted to occupational use only to satisfy FCC RF energy exposure requirements.
Before using this product, read the RF energy awareness information and operating instructions in the
Product Safety and RF Exposure booklet enclosed with your radio (Motorola Publication part number
68P81095C98) to ensure compliance with RF energy exposure limits.
For a list of Motorola-approved antennas, batteries, and other accessories, visit the following web site which
lists approved accessories: http://www.motorola.com/cgiss/index.shtml.
Computer Software Copyrights
The Motorola products described in this manual may include copyrighted Motorola computer programs stored
in semiconductor memories or other media. Laws in the United States and other countries preserve for
Motorola certain exclusive rights for copyrighted computer programs, including, but not limited to, the
exclusive right to copy or reproduce in any form the copyrighted computer program. Accordingly, any
copyrighted Motorola computer programs contained in the Motorola products described in this manual may
not be copied, reproduced, modified, reverse-engineered, or distributed in any manner without the express
written permission of Motorola. Furthermore, the purchase of Motorola products shall not be deemed to grant
either directly or by implication, estoppel, or otherwise, any license under the copyrights, patents or patent
applications of Motorola, except for the normal non-exclusive license to use that arises by operation of law in
the sale of a product.
Document Copyrights
No duplication or distribution of this document or any portion thereof shall take place without the express
written permission of Motorola. No part of this manual may be reproduced, distributed, or transmitted in any
form or by any means, electronic or mechanical, for any purpose without the express written permission of
Motorola.
Disclaimer
The information in this document is carefully examined, and is believed to be entirely reliable. However, no
responsibility is assumed for inaccuracies. Furthermore, Motorola reserves the right to make changes to any
products herein to improve readability, function, or design. Motorola does not assume any liability arising out
of the applications or use of any product or circuit described herein; nor does it cover any license under its
patent rights nor the rights of others.
MOTOROLA and The Stylized M logo are trademarks of Motorola, Inc.
All other product or service names are the property of their respective owners.
© 2005 Motorola, Inc. All rights reserved. Printed in U.S.A.
Note:
Before using this product, read the operating instructions for safe usage contained in the
Product Safety and RF Exposure booklet enclosed with your radio.
!
C a u t i o n

Table of Contents iii
6881096C25-B June, 2005
Table of Contents
Foreword .....................................................................................................................................................ii
Computer Software Copyrights ...................................................................................................................ii
Document Copyrights..................................................................................................................................ii
Disclaimer....................................................................................................................................................ii
List of Figures ................................................................................................x
List of Tables ................................................................................................xii
Related Publications...................................................................................xiii
Chapter 1 Test Equipment, Service Aids, and Service Tools.......... 1-1
1.1 Test Equipment..............................................................................................................................1-1
1.2 Service Aids...................................................................................................................................1-2
Chapter 2 DC Power Distribution........................................................ 2-1
2.1 DC Regulation and Distribution .....................................................................................................2-1
Chapter 3 Controller Theory of Operation.......................................... 3-1
3.1 Controller.......................................................................................................................................3-1
3.1.1 Microprocessor Circuitry...................................................................................................3-1
3.1.1.1 Memory Usage ........................................................................................................3-2
3.1.1.2 Control and Indicator Interface ................................................................................3-2
3.1.1.3 Serial Bus Control of Circuit Blocks.........................................................................3-2
3.1.1.4 Interface to RSS Programming................................................................................3-3
3.1.1.5 Storage of Customer-Specific Information...............................................................3-3
3.1.1.6 Sensing of Externally-Connected Accessories........................................................3-3
3.1.1.7 Microprocessor Power-Up, Power-Down and Reset Routine..................................3-3
3.1.1.8 Boot Mode Control................................................................................................... 3-4
3.1.1.9 Microprocessor 7.3975 MHz Clock.......................................................................... 3-4
3.1.1.10 Battery Gauge..........................................................................................................3-4
3.1.2 Audio Circuitry ..................................................................................................................3-4
3.1.2.1 Transmit and Receive Low-Level Audio Circuitry....................................................3-4
3.1.2.2 Audio Power Amplifier .............................................................................................3-5
3.1.2.3 Internal Microphone Audio Voice Path ....................................................................3-5
3.1.2.4 PTT Circuits.............................................................................................................3-5
3.1.2.5 VOX Operation ........................................................................................................3-6
3.1.2.6 Battery Charging Through Microphone Jack...........................................................3-6
3.1.2.7 Programming and Flashing Through Microphone Jack...........................................3-6

iv Table of Contents
June, 2005 6881096C25-B
Module 1: VHF 136-162, 146-174 MHz
Chapter 4 136-162 MHz VHF Theory Of Operation ............................ 4-1
4.1 Introduction....................................................................................................................................4-1
4.2 VHF Receiver.................................................................................................................................4-1
4.2.1 Receiver Front-End...........................................................................................................4-1
4.2.2 Receiver Back-End ...........................................................................................................4-2
4.3 VHF Transmitter.............................................................................................................................4-3
4.3.1 Transmit Power Amplifier..................................................................................................4-3
4.3.2 Antenna Switch.................................................................................................................4-3
4.3.3 Harmonic Filter..................................................................................................................4-3
4.3.4 Antenna Matching Network...............................................................................................4-4
4.3.5 Power Control...................................................................................................................4-4
4.4 VHF Frequency Generation Circuitry.............................................................................................4-4
4.4.1 Fractional-N Synthesizer...................................................................................................4-5
4.4.2 Voltage Controlled Oscillator (VCO) .................................................................................4-6
4.5 Keypad...........................................................................................................................................4-7
Chapter 5 146-174 MHz VHF Theory Of Operation ............................ 5-1
5.1 Introduction....................................................................................................................................5-1
5.2 VHF Receiver.................................................................................................................................5-1
5.2.1 Receiver Front-End...........................................................................................................5-1
5.2.2 Receiver Back-End ...........................................................................................................5-2
5.3 VHF Transmitter.............................................................................................................................5-3
5.3.1 Transmit Power Amplifier..................................................................................................5-3
5.3.2 Antenna Switch.................................................................................................................5-3
5.3.3 Harmonic Filter..................................................................................................................5-3
5.3.4 Antenna Matching Network...............................................................................................5-4
5.3.5 Power Control...................................................................................................................5-4
5.4 VHF Frequency Generation Circuitry.............................................................................................5-4
5.4.1 Fractional-N Synthesizer...................................................................................................5-5
5.4.2 Voltage Controlled Oscillator (VCO) .................................................................................5-6
5.5 Keypad...........................................................................................................................................5-7
Chapter 6 VHF Troubleshooting Tables............................................. 6-1
6.1 Troubleshooting Table for Receiver...............................................................................................6-1
6.2 Troubleshooting Table for Synthesizer..........................................................................................6-3
6.3 Troubleshooting Table for Transmitter...........................................................................................6-4
6.4 Troubleshooting Table for Board and IC Signals...........................................................................6-7
Chapter 7 VHF Schematic Diagrams, Overlays, and Parts Lists...... 7-1
7.1 Introduction....................................................................................................................................7-1
7.1.1 Notes For All Schematics and Circuit Boards...................................................................7-1
7.1.2 Six Layer Circuit Board .....................................................................................................7-3
7.2 Speaker and Microphone Schematic.............................................................................................7-3
7.2.1 Speaker and Microphone Parts List..................................................................................7-3

Table of Contents v
6881096C25-B June, 2005
Chapter 7 VHF 136-162 MHz (8486769Z02-A) Schematic Diagrams,
Overlays, and Parts Lists................................................... 7-5
Figure 7-3. VHF (136-162 MHz) Radio Circuit Block Interconnect Diagram (8486769Z02-A)...........7-5
Figure 7-4. VHF (136-162 MHz) Receiver Front End Schematic Diagram (8486769Z02-A)..............7-6
Figure 7-5. VHF (136-162 MHz) Receiver Back End Schematic Diagram (8486769Z02-A)..............7-7
Figure 7-6. VHF (136-162 MHz) Synthesizer Schematic Diagram (8486769Z02-A)..........................7-8
Figure 7-7. VHF (136-162 MHz) Voltage Controlled Oscillator Schematic
Diagram (8486769Z02-A).................................................................................................7-9
Figure 7-8. VHF (136-162 MHz) Transmitter and Power Control Schematic
Diagram (8486769Z02-A)...............................................................................................7-10
Figure 7-9. VHF (136-162 MHz) Controller Interconnect Schematic Diagram (8486769Z02-A)......7-11
Figure 7-10. VHF (136-162 MHz) Microprocessor Circuitry Schematic Diagram (8486769Z02-A)...7-12
Figure 7-11. VHF (136-162 MHz) Audio Circuitry Schematic Diagram (8486769Z02-A) ...................7-13
Figure 7-12. VHF (136-162 MHz) DC Regulation Schematic Diagram (8486769Z02-A)...................7-14
Figure 7-13. VHF (136-162 MHz) Keypad Board Schematic Diagram (8466565A03-A)....................7-15
Figure 7-14. VHF (136-162 MHz) Board Top Side View (8486769Z02-A) .........................................7-16
Figure 7-15. VHF (136-162 MHz) Board Bottom Side View (8486769Z02-A)....................................7-17
Figure 7-16. VHF (136-162 MHz) Keypad Board (8466565A03-B)....................................................7-18
VHF (136-162 MHz) Radio Parts List (8486769Z02-A).........................................................................7-19
VHF (136-162 MHz) Keypad Board Parts List (8466565A03-B)..........................................................7-22
Chapter 7 VHF 136-162 MHz Schematic Diagrams, Overlays,
and Parts Lists (8486769Z04-C)....................................... 7-23
Figure 7-17. VHF (136-162 MHz) Radio Circuit Block Interconnect Diagram (8486769Z04-C).........7-23
Figure 7-18. VHF (136-162 MHz) Receiver Front End Schematic Diagram (8486769Z04-C) ...........7-24
Figure 7-19. VHF (136-162 MHz) Receiver Back End Schematic Diagram (8486769Z04-C)............7-25
Figure 7-20. VHF (136-162 MHz) Synthesizer Schematic Diagram (8486769Z04-C)........................7-26
Figure 7-21. VHF (136-162 MHz) Voltage Controlled Oscillator Schematic
Diagram (8486769Z04-C) ..............................................................................................7-27
Figure 7-22. VHF (136-162 MHz) Transmitter and Power Control Schematic
Diagram (8486769Z04-C) ..............................................................................................7-28
Figure 7-23. VHF (136-162 MHz) Controller Interconnect Schematic Diagram (8486769Z04-C)......7-29
Figure 7-24. VHF (136-162 MHz) Microprocessor Circuitry Schematic Diagram (8486769Z04-C)...7-30
Figure 7-25. VHF (136-162 MHz) Audio Circuitry Schematic Diagram (8486769Z04-C)...................7-31
Figure 7-26. VHF (136-162 MHz) DC Regulation Schematic Diagram (8486769Z04-C)...................7-32
Figure 7-27. VHF (136-162 MHz) Keypad Board Schematic Diagram (8466565A03-B)....................7-33
Figure 7-28. VHF (136-162 MHz) Board Component Side View (8486769Z04-C).............................7-34
Figure 7-29. VHF (136-162 MHz) Board Solder Side View (8486769Z04-C).....................................7-35
Figure 7-30. VHF (136-162 MHz) Keypad Board (8466565A03-B)....................................................7-36
VHF (136-162 MHz) Radio Parts List (8486769Z04-C).........................................................................7-37
VHF (136-162 MHz) Keypad Board Parts List (8466565A03-B)...........................................................7-40
Chapter 7 VHF 146-174 MHz (8486342Z13-C) Schematic Diagrams,
Overlays, and Parts Lists................................................. 7-41
Figure 7-31. VHF (146-174 MHz) Radio Circuit Block Interconnect Diagram (8486342Z13-C).........7-41
Figure 7-32. VHF (146-174 MHz) Receiver Front End Schematic Diagram (8486342Z13-C) ...........7-42
Figure 7-33. VHF (146-174 MHz) Receiver Back End Schematic Diagram (8486342Z13-C)............7-43
Figure 7-34. VHF (146-174 MHz) Synthesizer Schematic Diagram (8486342Z13-C)........................7-44

vi Table of Contents
June, 2005 6881096C25-B
Figure 7-35. VHF (146-174 MHz) Voltage Controlled Oscillator Schematic
Diagram (8486342Z13-C)...............................................................................................7-45
Figure 7-36. VHF (146-174 MHz) Transmitter and Power Control Schematic
Diagram (8486342Z13-C)...............................................................................................7-46
Figure 7-37. VHF (146-174 MHz) Controller Interconnect Schematic Diagram (8486342Z13-C)......7-47
Figure 7-38. VHF (146-174 MHz) Microprocessor Circuitry Schematic Diagram (8486342Z13-C)...7-48
Figure 7-39. VHF (146-174 MHz) Audio Circuitry Schematic Diagram (8486342Z13-C)...................7-49
Figure 7-40. VHF (146-174 MHz) DC Regulation Schematic Diagram (8486342Z13-C)...................7-50
Figure 7-41. VHF (146-174 MHz) Keypad Board Schematic Diagram (8466565A03-B)....................7-51
Figure 7-42. VHF (146-174 MHz) Board, Top Side (8486342Z13-C).................................................7-52
Figure 7-43. VHF (146-174 MHz) Board, Bottom Side (8486342Z13-C)............................................7-53
Figure 7-44. VHF (146-174 MHz) Keypad Board (8466565A03-B)....................................................7-54
VHF (146-174 MHz) Radio Parts List (8486342Z13-C) ........................................................................7-55
VHF (146-174 MHz) Keypad Board Parts List (8466565A03-B) ...........................................................7-58
Chapter 7 VHF 146-174 MHz Schematic Diagrams, Overlays,
and Parts Lists (8486769Z04-C)....................................... 7-59
Figure 7-45. VHF (146-174 MHz) Radio Circuit Block Interconnect Diagram (8486769Z04-C) .........7-59
Figure 7-46. VHF (146-174 MHz) Receiver Front End Schematic Diagram (8486769Z04-C)............7-60
Figure 7-47. VHF (146-174 MHz) Receiver Back End Schematic Diagram (8486769Z04-C)............7-61
Figure 7-48. VHF (146-174 MHz) Synthesizer Schematic Diagram (8486769Z04-C)........................7-62
Figure 7-49. VHF (146-174 MHz) Voltage Controlled Oscillator Schematic
Diagram 8486769Z04-C)................................................................................................7-63
Figure 7-50. VHF (146-174 MHz) Transmitter and Power Control Schematic
Diagram (8486769Z04-C)...............................................................................................7-64
Figure 7-51. VHF (146-174 MHz) Controller Interconnect Schematic Diagram (8486769Z04-C)......7-65
Figure 7-52. VHF (146-174 MHz) Microprocessor Circuitry Schematic Diagram (8486769Z04-C)...7-66
Figure 7-53. VHF (146-174 MHz) Audio Circuitry Schematic Diagram (8486769Z04-C)...................7-67
Figure 7-54. VHF (146-174 MHz) DC Regulation Schematic Diagram (8486769Z04-C)...................7-68
Figure 7-55. VHF (146-174 MHz) Keypad Board Schematic Diagram (8466565A03-B)....................7-69
Figure 7-56. VHF (146-174 MHz) Board Component Side View (8486769Z04-C).............................7-70
Figure 7-57. VHF (146-174 MHz) Board Solder Side View (8486769Z04-C).....................................7-71
Figure 7-58. VHF (146-174 MHz) Keypad Board (8466565A03-B)....................................................7-72
VHF (146-174 MHz) Radio Parts List (8486769Z04-C).........................................................................7-73
VHF (146-174 MHz) Keypad Board Parts List (8466565A03-B) ...........................................................7-76
Module 2: UHF 403-440, 438-470, 465-495 MHz
Chapter 8 403-440 MHz UHF Theory Of Operation............................ 8-1
8.1 Introduction....................................................................................................................................8-1
8.2 UHF Receiver ................................................................................................................................8-1
8.2.1 Receiver Front End...........................................................................................................8-1
8.2.2 Receiver Back End ...........................................................................................................8-2
8.3 UHF Transmitter ............................................................................................................................8-3
8.3.1 Transmitter Power Amplifier..............................................................................................8-3
8.3.2 Antenna Switch.................................................................................................................8-3
8.3.3 Harmonic Filter..................................................................................................................8-3
8.3.4 Antenna Matching Network...............................................................................................8-4
8.3.5 Power Control...................................................................................................................8-4

Table of Contents vii
6881096C25-B June, 2005
8.4 UHF Frequency Generation Circuitry ............................................................................................8-4
8.4.1 Fractional-N Synthesizer ..................................................................................................8-5
8.4.2 Voltage Controlled Oscillator (VCO).................................................................................8-6
8.5 Keypad...........................................................................................................................................8-7
Chapter 9 438-470 MHz UHF Theory Of Operation............................ 9-1
9.1 Introduction....................................................................................................................................9-1
9.2 UHF Receiver ................................................................................................................................9-1
9.2.1 Receiver Front End...........................................................................................................9-1
9.2.2 Receiver Back End ...........................................................................................................9-2
9.3 UHF Transmitter............................................................................................................................9-3
9.3.1 Transmitter Power Amplifier .............................................................................................9-3
9.3.2 Antenna Switch.................................................................................................................9-3
9.3.3 Harmonic Filter .................................................................................................................9-3
9.3.4 Antenna Matching Network...............................................................................................9-4
9.3.5 Power Control...................................................................................................................9-4
9.4 UHF Frequency Generation Circuitry ............................................................................................9-4
9.4.1 Fractional-N Synthesizer ..................................................................................................9-5
9.4.2 Voltage Controlled Oscillator (VCO).................................................................................9-6
9.5 Keypad...........................................................................................................................................9-7
Chapter 10 465-495 MHz UHF Theory Of Operation.......................... 10-1
10.1 Introduction..................................................................................................................................10-1
10.2 UHF Receiver..............................................................................................................................10-1
10.2.1 Receiver Front End.........................................................................................................10-1
10.2.2 Receiver Back End .........................................................................................................10-2
10.3 UHF Transmitter..........................................................................................................................10-3
10.3.1 Transmitter Power Amplifier ...........................................................................................10-3
10.3.2 Antenna Switch...............................................................................................................10-3
10.3.3 Harmonic Filter ...............................................................................................................10-3
10.3.4 Antenna Matching Network.............................................................................................10-4
10.3.5 Power Control.................................................................................................................10-4
10.4 UHF Frequency Generation Circuitry ..........................................................................................10-4
10.4.1 Fractional-N Synthesizer ................................................................................................10-5
10.4.2 Voltage Controlled Oscillator (VCO)...............................................................................10-6
10.5 Keypad.........................................................................................................................................10-7
Chapter 11 UHF Troubleshooting Tables........................................... 11-1
11.1 Troubleshooting Table for Receiver.............................................................................................11-1
11.2 Troubleshooting Table for Synthesizer........................................................................................11-3
11.3 Troubleshooting Table for Transmitter.........................................................................................11-4
11.4 Troubleshooting Table for Board and IC Signals.........................................................................11-6
Chapter 12 UHF Schematic Diagrams, Overlays, and Parts Lists ... 12-1
12.1 Introduction..................................................................................................................................12-1
12.1.1 Notes For All Schematics and Circuit Boards.................................................................12-1
12.1.2 Six Layer Circuit Board...................................................................................................12-3
12.2 Speaker and Microphone Schematic...........................................................................................12-3
12.2.1 Speaker and Microphone Parts List................................................................................12-3

viii Table of Contents
June, 2005 6881096C25-B
Chapter 12 UHF 403-440 MHz (8486635Z03-O) Schematic Diagrams,
Overlays, and Parts Lists................................................. 12-5
Figure 12-3. UHF (403-440 MHz) Radio Circuit Block Diagram (8486635Z03-O)..............................12-5
Figure 12-4. UHF (403-440 MHz) Receiver Front End Schematic Diagram (8486635Z03-O) ...........12-6
Figure 12-5. UHF (403-440 MHz) Receiver Back End Schematic Diagram (8486635Z03-O)............12-7
Figure 12-6. UHF (403-440 MHz) Synthesizer Schematic Diagram (8486635Z03-O) .......................12-8
Figure 12-7. UHF (403-440 MHz) Voltage Controlled Oscillator Schematic
Diagram (8486635Z03-O) ..............................................................................................12-9
Figure 12-8. UHF (403-440 MHz) Transmitter and Power Control Schematic
Diagram (8486635Z03-O) ............................................................................................12-10
Figure 12-9. UHF (403-440 MHz) Controller Interconnect Schematic Diagram (8486635Z03-O)....12-11
Figure 12-10. UHF (403-440 MHz) Microprocessor Circuitry Schematic Diagram (8486635Z03-O) 12-12
Figure 12-11. UHF (403-440MHz) Audio Circuitry Schematic Diagram (8486635Z03-O)..................12-13
Figure 12-12. UHF (403-440 MHz) DC Regulation Schematic Diagram (8486635Z03-O).................12-14
Figure 12-13. UHF (403-440 MHz) Keypad Board Schematic Diagram (8466565A03-B)..................12-15
Figure 12-14. UHF (403-440 MHz) Board Top Side View (8486635Z03-O).......................................12-16
Figure 12-15. UHF (403-440 MHz) Board Bottom Side View (8486635Z03-O)..................................12-17
Figure 12-16. UHF (403-440 MHz) Keypad Board (8466565A03-B)..................................................12-18
UHF (403-440 MHz) Radio Parts List (8486635Z03-O) ......................................................................12-19
UHF (403-440 MHz) Keypad Board Parts List (8466565A03-B)........................................................12-22
Chapter 12 UHF 438-470 MHz (8486348Z13-C) Schematic Diagrams,
Overlays, and Parts Lists............................................... 12-23
Figure 12-17. UHF (438-470 MHz) Radio Circuit Block Diagram (8486348Z13-C)............................12-23
Figure 12-18. UHF (438-470 MHz) Receiver Front End Schematic Diagram (8486348Z13-C) .........12-24
Figure 12-19. UHF (438-470 MHz) Receiver Back End Schematic Diagram (8486348Z13-C)..........12-25
Figure 12-20. UHF (438-470 MHz) Synthesizer Schematic Diagram (8486348Z13-C)......................12-26
Figure 12-21. UHF (438-470 MHz) Voltage Controlled Oscillator Schematic
Diagram (8486348Z13-C).............................................................................................12-27
Figure 12-22. UHF (438-470 MHz) Transmitter and Power Control Schematic
Diagram (8486348Z13-C).............................................................................................12-28
Figure 12-23. UHF (438-470 MHz) Controller Interconnect Schematic Diagram (8486348Z13-C)....12-29
Figure 12-24. UHF (438-470 MHz) Microprocessor Circuitry Schematic Diagram (8486348Z13-C).12-30
Figure 12-25. UHF (438-470 MHz) Audio Circuitry Schematic Diagram (8486348Z13-C).................12-31
Figure 12-26. UHF (438-470 MHz) DC Regulation Schematic Diagram (8486348Z13-C).................12-32
Figure 12-27. UHF (438-470 MHz) Keypad Option Schematic Diagram (8466565A03-B).................12-33
Figure 12-28. UHF (438-470 MHz) Board Top Side View (8486348Z13-C).......................................12-34
Figure 12-29. UHF (438-470 MHz) Board Bottom Side View (8486348Z13-C)..................................12-35
Figure 12-30. UHF (438-470 MHz) Keypad Board (8466565A03-B)..................................................12-36
UHF (438-470 MHz) Radio Parts List (8486348Z13-C).......................................................................12-37
UHF (438-470 MHz) Keypad Board Parts List (8466565A03-B)........................................................12-40
Chapter 12 UHF 465-495 MHz (8486634Z02-O) Schematic Diagrams,
Overlays, and Parts Lists............................................... 12-41
Figure 12-31. UHF (465-495 MHz) Radio Circuit Block Diagram (8486634Z02-O)............................12-41
Figure 12-32. UHF (465-495 MHz) Receiver Front End Schematic Diagram (8486634Z02-O) .........12-42
Figure 12-33. UHF (465-495 MHz) Receiver Back End Schematic Diagram (8486634Z02-O)..........12-43
Figure 12-34. UHF (465-495 MHz) Synthesizer Schematic Diagram (8486634Z02-O) .....................12-44

Table of Contents ix
6881096C25-B June, 2005
Figure 12-35. UHF (465-495 MHz) Voltage Controlled Oscillator Schematic
Diagram (8486634Z02-O)............................................................................................12-45
Figure 12-36. UHF (465-495 MHz) Transmitter and Power Control Schematic
Diagram (8486634Z02-O)............................................................................................12-46
Figure 12-37. UHF (465-495 MHz) Controller Interconnect Schematic Diagram (8486634Z02-O)....12-47
Figure 12-38. UHF (465-495 MHz) Microprocessor Circuitry Schematic Diagram (8486634Z02-O) 12-48
Figure 12-39. UHF (465-495 MHz) Audio Circuitry Schematic Diagram (8486634Z02-O).................12-49
Figure 12-40. UHF (465-495 MHz) DC Regulation Schematic Diagram (8486634Z02-O).................12-50
Figure 12-41. UHF (465-495 MHz) Keypad Board Schematic Diagram (8466565A03-B) .................12-51
Figure 12-42. UHF (465-495 MHz) Board Top Side View (8486634Z02-O).......................................12-52
Figure 12-43. UHF (465-495 MHz) Board Bottom Side View (8486634Z02-O) .................................12-53
Figure 12-44. UHF (465-495 MHz) Keypad Board (8466565A03-B)..................................................12-54
UHF (465-495 MHz) Radio Parts List (8486634Z02-O)......................................................................12-55
UHF (465-495 MHz) Keypad Board Parts List (8466565A03-B)........................................................12-58
INDEX................................................................................... 1-1

xTable of Contents
June, 2005 6881096C25-B
List of Figures
Figure 1-1. Programming/Test Cable..................................................................................................1-4
Figure 1-2. Wiring of the Connectors..................................................................................................1-4
Figure 2-1. DC Power Distribution Block Diagram..............................................................................2-1
Figure 4-1. VHF Receiver Block Diagram...........................................................................................4-1
Figure 4-2. VHF Transmitter Block Diagram.......................................................................................4-3
Figure 4-3. VHF Frequency Generation Unit Block Diagram..............................................................4-5
Figure 4-4. VHF Synthesizer Block Diagram......................................................................................4-6
Figure 4-5. VHF VCO Block Diagram.................................................................................................4-7
Figure 4-6. Keypad Block Diagram.....................................................................................................4-7
Figure 5-1. VHF Receiver Block Diagram...........................................................................................5-1
Figure 5-2. VHF Transmitter Block Diagram.......................................................................................5-3
Figure 5-3. VHF Frequency Generation Unit Block Diagram..............................................................5-5
Figure 5-4. VHF Synthesizer Block Diagram......................................................................................5-6
Figure 5-5. VHF VCO Block Diagram.................................................................................................5-7
Figure 5-6. Keypad Block Diagram.....................................................................................................5-7
Figure 7-1. Six-Layer Circuit Board: Copper Steps in Layer Sequence..............................................7-3
Figure 7-2. Speaker and Microphone Schematic................................................................................7-3
Figure 7-3. VHF (136-162 MHz) Radio Circuit Block Interconnect Diagram (8486769Z02-A) ...........7-5
Figure 7-4. VHF (136-162 MHz) Receiver Front End Schematic Diagram (8486769Z02-A)..............7-6
Figure 7-5. VHF (136-162 MHz) Receiver Back End Schematic Diagram (8486769Z02-A)..............7-7
Figure 7-6. VHF (136-162 MHz) Synthesizer Schematic Diagram (8486769Z02-A)..........................7-8
Figure 7-7. VHF (136-162 MHz) Voltage Controlled Oscillator Schematic
Diagram (8486769Z02-A).................................................................................................7-9
Figure 7-8. VHF (136-162 MHz) Transmitter and Power Control Schematic
Diagram (8486769Z02-A)...............................................................................................7-10
Figure 7-9. VHF (136-162 MHz) Controller Interconnect Schematic Diagram (8486769Z02-A) ......7-11
Figure 7-10. VHF (136-162 MHz) Microprocessor Circuitry Schematic Diagram (8486769Z02-A)...7-12
Figure 7-11. VHF (136-162 MHz) Audio Circuitry Schematic Diagram (8486769Z02-A) ...................7-13
Figure 7-12. VHF (136-162 MHz) DC Regulation Schematic Diagram (8486769Z02-A) ...................7-14
Figure 7-13. VHF (136-162 MHz) Keypad Board Schematic Diagram (8466565A03-A)....................7-15
Figure 7-14. VHF (136-162 MHz) Board Top Side View (8486769Z02-A) .........................................7-16
Figure 7-15. VHF (136-162 MHz) Board Bottom Side View (8486769Z02-A)....................................7-17
Figure 7-16. VHF (136-162 MHz) Keypad Board (8466565A03-B)....................................................7-18
Figure 7-17. VHF (136-162 MHz) Radio Circuit Block Interconnect Diagram (8486769Z04-C) .........7-23
Figure 7-18. VHF (136-162 MHz) Receiver Front End Schematic Diagram (8486769Z04-C)............7-24
Figure 7-19. VHF (136-162 MHz) Receiver Back End Schematic Diagram (8486769Z04-C)............7-25
Figure 7-20. VHF (136-162 MHz) Synthesizer Schematic Diagram (8486769Z04-C)........................7-26
Figure 7-21. VHF (136-162 MHz) Voltage Controlled Oscillator Schematic
Diagram (8486769Z04-C)...............................................................................................7-27
Figure 7-22. VHF (136-162 MHz) Transmitter and Power Control Schematic
Diagram (8486769Z04-C)...............................................................................................7-28
Figure 7-23. VHF (136-162 MHz) Controller Interconnect Schematic Diagram (8486769Z04-C)......7-29
Figure 7-24. VHF (136-162 MHz) Microprocessor Circuitry Schematic Diagram (8486769Z04-C)...7-30
Figure 7-25. VHF (136-162 MHz) Audio Circuitry Schematic Diagram (8486769Z04-C)...................7-31
Figure 7-26. VHF (136-162 MHz) DC Regulation Schematic Diagram (8486769Z04-C)...................7-32
Figure 7-27. VHF (136-162 MHz) Keypad Board Schematic Diagram (8466565A03-B)....................7-33
Figure 7-28. VHF (136-162 MHz) Board Component Side View (8486769Z04-C).............................7-34
Figure 7-29. VHF (136-162 MHz) Board Solder Side View (8486769Z04-C).....................................7-35
Figure 7-30. VHF (136-162 MHz) Keypad Board (8466565A03-B)....................................................7-36
Figure 7-31. VHF (146-174 MHz) Radio Circuit Block Interconnect Diagram (8486342Z13-C) .........7-41

Table of Contents xi
6881096C25-B June, 2005
Figure 7-32. VHF (146-174 MHz) Receiver Front End Schematic Diagram (8486342Z13-C) ...........7-42
Figure 7-33. VHF (146-174 MHz) Receiver Back End Schematic Diagram (8486342Z13-C)............7-43
Figure 7-34. VHF (146-174 MHz) Synthesizer Schematic Diagram (8486342Z13-C)........................7-44
Figure 7-35. VHF (146-174 MHz) Voltage Controlled Oscillator Schematic
Diagram (8486342Z13-C) ..............................................................................................7-45
Figure 7-36. VHF (146-174 MHz) Transmitter and Power Control Schematic
Diagram (8486342Z13-C) ..............................................................................................7-46
Figure 7-37. VHF (146-174 MHz) Controller Interconnect Schematic Diagram (8486342Z13-C)......7-47
Figure 7-38. VHF (146-174 MHz) Microprocessor Circuitry Schematic Diagram (8486342Z13-C)...7-48
Figure 7-39. VHF (146-174 MHz) Audio Circuitry Schematic Diagram (8486342Z13-C)...................7-49
Figure 7-40. VHF (146-174 MHz) DC Regulation Schematic Diagram (8486342Z13-C)...................7-50
Figure 7-41. VHF (146-174 MHz) Keypad Board Schematic Diagram (8466565A03-B)....................7-51
Figure 7-42. VHF (146-174 MHz) Board, Top Side (8486342Z13-C).................................................7-52
Figure 7-43. VHF (146-174 MHz) Board, Bottom Side (8486342Z13-C)............................................7-53
Figure 7-44. VHF (146-174 MHz) Keypad Board (8466565A03-B)....................................................7-54
Figure 7-45. VHF (146-174 MHz) Radio Circuit Block Interconnect Diagram (8486769Z04-C).........7-59
Figure 7-46. VHF (146-174 MHz) Receiver Front End Schematic Diagram (8486769Z04-C) ...........7-60
Figure 7-47. VHF (146-174 MHz) Receiver Back End Schematic Diagram (8486769Z04-C)............7-61
Figure 7-48. VHF (146-174 MHz) Synthesizer Schematic Diagram (8486769Z04-C)........................7-62
Figure 7-49. VHF (146-174 MHz) Voltage Controlled Oscillator Schematic
Diagram (8486769Z04-C) ..............................................................................................7-63
Figure 7-50. VHF (146-174 MHz) Transmitter and Power Control Schematic
Diagram (8486769Z04-C) ..............................................................................................7-64
Figure 7-51. VHF (146-174 MHz) Controller Interconnect Schematic Diagram (8486769Z04-C)......7-65
Figure 7-52. VHF (146-174 MHz) Microprocessor Circuitry Schematic Diagram (8486769Z04-C)...7-66
Figure 7-53. VHF (146-174 MHz) Audio Circuitry Schematic Diagram (8486769Z04-C)...................7-67
Figure 7-54. VHF (146-174 MHz) DC Regulation Schematic Diagram (8486769Z04-C)...................7-68
Figure 7-55. VHF (146-174 MHz) Keypad Board Schematic Diagram (8466565A03-B)....................7-69
Figure 7-56. VHF (146-174 MHz) Board Component Side View (8486769Z04-C).............................7-70
Figure 7-57. VHF (146-174 MHz) Board Solder Side View (8486769Z04-C).....................................7-71
Figure 7-58. VHF (146-174 MHz) Keypad Board (8466565A03-B)....................................................7-72
Figure 8-1. UHF Receiver Block Diagram ..........................................................................................8-1
Figure 8-2. UHF Transmitter Block Diagram ......................................................................................8-3
Figure 8-3. UHF Frequency Generation Unit Block Diagram ............................................................. 8-5
Figure 8-4. UHF Synthesizer Block Diagram......................................................................................8-6
Figure 8-5. UHF VCO Block Diagram.................................................................................................8-7
Figure 8-6. Keypad Block Diagram.....................................................................................................8-7
Figure 9-1. UHF Receiver Block Diagram ..........................................................................................9-1
Figure 9-2. UHF Transmitter Block Diagram ......................................................................................9-3
Figure 9-3. UHF Frequency Generation Unit Block Diagram ............................................................. 9-5
Figure 9-4. UHF Synthesizer Block Diagram......................................................................................9-6
Figure 9-5. UHF VCO Block Diagram.................................................................................................9-7
Figure 9-6. Keypad Block Diagram.....................................................................................................9-7
Figure 10-1. UHF Receiver Block Diagram ........................................................................................10-1
Figure 10-2. UHF Transmitter Block Diagram ....................................................................................10-3
Figure 10-3. UHF Frequency Generation Unit Block Diagram ...........................................................10-5
Figure 10-4. UHF Synthesizer Block Diagram....................................................................................10-6
Figure 10-5. UHF VCO Block Diagram...............................................................................................10-7
Figure 10-6. Keypad Block Diagram...................................................................................................10-7
Figure 12-1. Six-Layer Circuit Board: Copper Steps in Layer Sequence ...........................................12-3
Figure 12-2. Speaker and Microphone Schematic .............................................................................12-3
Figure 12-3. UHF (403-440 MHz) Radio Circuit Block Diagram (8486635Z03-O) .............................12-5
Figure 12-4. UHF (403-440 MHz) Receiver Front End Schematic Diagram (8486635Z03-O)...........12-6
Figure 12-5. UHF (403-440 MHz) Receiver Back End Schematic Diagram (8486635Z03-O) ...........12-7

xii Table of Contents
June, 2005 6881096C25-B
Figure 12-6. UHF (403-440 MHz) Synthesizer Schematic Diagram (8486635Z03-O) .......................12-8
Figure 12-7. UHF (403-440 MHz) Voltage Controlled Oscillator Schematic
Diagram (8486635Z03-O) ..............................................................................................12-9
Figure 12-8. UHF (403-440 MHz) Transmitter and Power Control Schematic
Diagram (8486635Z03-O) ............................................................................................12-10
Figure 12-9. UHF (403-440 MHz) Controller Interconnect Schematic Diagram (8486635Z03-O)....12-11
Figure 12-10. UHF (403-440 MHz) Microprocessor Circuitry Schematic Diagram (8486635Z03-O) 12-12
Figure 12-11. UHF (403-440MHz) Audio Circuitry Schematic Diagram (8486635Z03-O)..................12-13
Figure 12-12. UHF (403-440 MHz) DC Regulation Schematic Diagram (8486635Z03-O).................12-14
Figure 12-13. UHF (403-440 MHz) Keypad Board Schematic Diagram (8466565A03-B)..................12-15
Figure 12-14. UHF (403-440 MHz) Board Top Side View (8486635Z03-O).......................................12-16
Figure 12-15. UHF (403-440 MHz) Board Bottom Side View (8486635Z03-O)..................................12-17
Figure 12-16. UHF (403-440 MHz) Keypad Board (8466565A03-B)..................................................12-18
Figure 12-17. UHF (438-470 MHz) Radio Circuit Block Diagram (8486348Z13-C)............................12-23
Figure 12-18. UHF (438-470 MHz) Receiver Front End Schematic Diagram (8486348Z13-C) .........12-24
Figure 12-19. UHF (438-470 MHz) Receiver Back End Schematic Diagram (8486348Z13-C)..........12-25
Figure 12-20. UHF (438-470 MHz) Synthesizer Schematic Diagram (8486348Z13-C)......................12-26
Figure 12-21. UHF (438-470 MHz) Voltage Controlled Oscillator Schematic
Diagram (8486348Z13-C).............................................................................................12-27
Figure 12-22. UHF (438-470 MHz) Transmitter and Power Control Schematic
Diagram (8486348Z13-C).............................................................................................12-28
Figure 12-23. UHF (438-470 MHz) Controller Interconnect Schematic Diagram (8486348Z13-C)....12-29
Figure 12-24. UHF (438-470 MHz) Microprocessor Circuitry Schematic Diagram (8486348Z13-C).12-30
Figure 12-25. UHF (438-470 MHz) Audio Circuitry Schematic Diagram (8486348Z13-C).................12-31
Figure 12-26. UHF (438-470 MHz) DC Regulation Schematic Diagram (8486348Z13-C).................12-32
Figure 12-27. UHF (438-470 MHz) Keypad Option Schematic Diagram (8466565A03-B).................12-33
Figure 12-28. UHF (438-470 MHz) Board Top Side View (8486348Z13-C).......................................12-34
Figure 12-29. UHF (438-470 MHz) Board Bottom Side View (8486348Z13-C)..................................12-35
Figure 12-30. UHF (438-470 MHz) Keypad Board (8466565A03-B)..................................................12-36
Figure 12-31. UHF (465-495 MHz) Radio Circuit Block Diagram (8486634Z02-O)............................12-41
Figure 12-32. UHF (465-495 MHz) Receiver Front End Schematic Diagram (8486634Z02-O) .........12-42
Figure 12-33. UHF (465-495 MHz) Receiver Back End Schematic Diagram (8486634Z02-O)..........12-43
Figure 12-34. UHF (465-495 MHz) Synthesizer Schematic Diagram (8486634Z02-O) .....................12-44
Figure 12-35. UHF (465-495 MHz) Voltage Controlled Oscillator Schematic
Diagram (8486634Z02-O) ............................................................................................12-45
Figure 12-36. UHF (465-495 MHz) Transmitter and Power Control Schematic
Diagram (8486634Z02-O) ............................................................................................12-46
Figure 12-37. UHF (465-495 MHz) Controller Interconnect Schematic Diagram (8486634Z02-O)....12-47
Figure 12-38. UHF (465-495 MHz) Microprocessor Circuitry Schematic Diagram (8486634Z02-O) 12-48
Figure 12-39. UHF (465-495 MHz) Audio Circuitry Schematic Diagram (8486634Z02-O).................12-49
Figure 12-40. UHF (465-495 MHz) DC Regulation Schematic Diagram (8486634Z02-O).................12-50
Figure 12-41. UHF (465-495 MHz) Keypad Board Schematic Diagram (8466565A03-B)..................12-51
Figure 12-42. UHF (465-495 MHz) Board Top Side View (8486634Z02-O).......................................12-52
Figure 12-43. UHF (465-495 MHz) Board Bottom Side View (8486634Z02-O)..................................12-53
Figure 12-44. UHF (465-495 MHz) Keypad Board (8466565A03-B)..................................................12-54

Table of Contents xiii
6881096C25-B June 6, 2005
List of Tables
Table 1-1. Recommended Test Equipment....................................................................................... 1-1
Table 1-2. Service Aids .....................................................................................................................1-2
Table 1-3. Recommended Service Tools..........................................................................................1-2
Table 2-1. Voltage Regulators...........................................................................................................2-2
Table 3-1. Radio Memory Requirements...........................................................................................3-1
Table 3-2. SPI Bus Signal Definitions................................................................................................3-2
Table 6-1. Troubleshooting Table for Receiver.................................................................................6-1
Table 6-2. Troubleshooting Table for Synthesizer.............................................................................6-3
Table 6-3. Troubleshooting Table for Transmitter.............................................................................6-4
Table 6-4. Troubleshooting Table for Board and IC Signals .............................................................6-7
Table 11-1. Troubleshooting Table for Receiver...............................................................................11-1
Table 11-2. Troubleshooting Table for Synthesizer...........................................................................11-3
Table 11-3. Troubleshooting Table for Transmitter...........................................................................11-4
Table 11-4. Troubleshooting Table for Board and IC Signals ...........................................................11-6
Related Publications
PR400 Basic Service Manual .........................................................................................................6881096C24
PR400 Non-Display User Guide.....................................................................................................6881096C27
PR400 Half-Keypad User Guide.....................................................................................................6881096C26
PR400 Full-Keypad User Guide......................................................................................................6881096C23
Product Safety and RF Exposure Compliance ...............................................................................6881095C98
PR400 User Guide CDROM..............................................................................................................HKLN4219

xiv Table of Contents
June, 2005 6881096C25-B

Chapter 1 Test Equipment, Service Aids, and
Service Tools
1.1 Test Equipment
Table 1-1 lists test equipment required to service the PR400 Radios.
Table 1-1. Recommended Test Equipment
Motorola Part No. Description Characteristics Application
R2600 series System analyzer This item will substitute for
items with an asterisk (*)
Frequency/deviation meter and
signal generator for wide-range
troubleshooting and alignment
*R1074A Fluke 87 digital multi-
meter
True RMS metering,
200 kHz frequency
counter, 32-segment bar
graph with backlit display
Digital voltmeter is recom-
mended for AC/DC voltage and
current measurements
Fluke 85 RF probe 500 MHz, 30 VAC max Use with Fluke 87 digital multi-
meter for RF voltage measure-
ments.
*R1377A AC voltmeter 1 mV to 300 mV, 10 mega-
ohm input impedance
Audio voltage measurements
R1611A Dual channel
100 MHz oscillo-
scope (Agillent)
Two-channel, 100 MHz
bandwidth, 200 M sample
rate/sec, 2 MB memory/
channel
Waveform measurements
S1339A RF millivolt meter 100 µV to 3V RF, 10 kHz to
1 GHz frequency range
RF level measurements
*R1013B or
*R1370A
SINAD meter or
SINAD meter with
RMS
Without RMS audio voltme-
ter or
With RMS audio voltmeter
Receiver sensitivity measure-
ments

June, 2005 6881096C24-B
1-2 Test Equipment, Service Aids, and Service Tools: Service Aids
1.2 Service Aids
Ta b le 1 - 2 lists service aids recommended for working on the PR400 Radios. While all of these items
are available from Motorola, most are standard shop equipment items, and any equivalent item
capable of the same performance may be substituted for the item listed.
Table 1-2. Service Aids
Motorola Part
No. Description Application
RLN4460 Portable Test Set Enables connection to the audio/accessory jack.
Allows switching for radio testing.
RLN4510 Battery Interface Regulates DC current and voltage between radio and
power supply.
RVN4191 Customer Programming Soft-
ware and Global Tuner Software
on CD Rom
Program customer option and channel data.
AAPMKN4004 Programming Test Cable Connects radio to RIB (PLN4008).
AAPMKN4003 Radio-to-Radio Cloning Cable Allows a radio to be duplicated from a master radio by
transferring programmed data from the master radio to
the other.
RLN4008 Radio Interface Box Enables communications between the radio and the
computer’s serial communications adapter.
5886564Z01 RF Adaptor Adapts radio’s antenna port to BNC cabling of test
equipment.
0180305K08 Shop Battery Eliminator Interconnects radio to power supply.
HSN9412 Wall-Mounted Power Supply Used to supply power to the RIB (120 VAC).
3080369B71 or
3080369B72
Computer Interface Cable Use B72 for the IBM PC AT or newer (9-pin serial
port). Use B71 for older models (25-pin serial port).
Connects the computer’s serial communications
adapter to the RIB (PLN4008).
6686533Z01 Knob Remover/Chassis Opener Used to remove the front cover assembly.
HKN9216 IBM Computer Interface Cable Connection from computer to RIB.
8180384N65 Housing Eliminator Allows testing of the radio outside of the housing.
Table 1-3. Recommended Service Tools
Motorola Part
No. Description Application
RSX4043A TORX screwdriver Tighten and remove chassis screws
6680387A70 T6 TORX bit Removable TORX screwdriver bit
R1453A Digital readout solder station Digitally controlled soldering iron
RLN4062A Hot air workstation, 120 V Tool for hot air soldering/desoldering of surface
mounted integrated circuits

6881096C24-B June 6, 2005
Test Equipment, Service Aids, and Service Tools: Service Aids 1-3
0180386A78 Illuminated magnifying glass with
lens attachment Illumination and magnification of components
0180302E51 Master lens system
0180386A82 Anti-static grounding kit Used during all radio assembly and disassembly pro-
cedures
6684253C72 Straight prober
6680384A98 Brush
1010041A86 Solder (RMA type), 63/67,
0.5mm diameter, 1 lb. spool
0180303E45 SMD tool kit (included with
R1319A)
R1319A ChipMaster (110 V) Surface mount removal and assembly of surface
mounted integrated circuits and/or rework station
shields. Includes 5 nozzles.
R1321A ChipMaster (220 V)
ChipMaster Nozzles:
6680332E83 PLCC-28* nozzle
Soldering and Un-soldering IC’s
6680332E82 PLCC-44* nozzle
6680332E94 PLCC-52 nozzle
6680332E96 PLCC-84 nozzle
6680334E67 QFP-160 nozzle
6680333E46 SOL-18 nozzle
6680332E84 SOIC-20 nozzle
6680332E87 SOL-20J nozzle
6680333E45 SOL-24 nozzle
6680333E55 TSOP-64 nozzle
* Included with ChipMaster packages
Table 1-3. Recommended Service Tools (Continued)
Motorola Part
No. Description Application

June, 2005 6881096C24-B
1-4 Test Equipment, Service Aids, and Service Tools: Service Aids
Programming/Test Cable
Figure 1-1. Programming/Test Cable
Figure 1-2. Wiring of the Connectors
25 POSITION
FEMALE CONNECTOR
25 POSITION
MALE CONNECTOR
36.0”
CABLE
36.0”
CABLE
P1
P2 P3
P2
25 pin Male D Connector
Components molded inside
1
5
24
7
20
8
15
16
9
47
ohm
33K
+
1UF,16V 5%
Orange
Blue
White
Spiral
Yellow
P1
2.5mm stereo and
3.5mm
1
2
5
3
4
3.5mm Tip
(Speaker +)
3.5mm
Sleeve
2.5mm Tip
(Microphone)
2.5mm
2.5mm
Center
P3
25 pin Female
D Connector
1
15
4
11
1
2
3
4
5
3.5mm mono
2.5mm stereo
To Test Box
To Test Box