Motorola Professional CDM1550 LS+ Operating and maintenance manual

CDM1550•LS+™
200 MHz
700 MHz
Professional Series
Two-Way Radio Detailed Service Manual

Product Software License Agreement
THIS LICENSE AGREEMENT BETWEEN YOU, THE USER, AND MOTOROLA, APPLIES TO THE SOFT-
WARE EMBEDDED IN OR DELIVERED WITH THE ACCOMPANYING MOTOROLA PRODUCT ("SOFT-
WARE"), AND IS APPLICABLE UNLESS A SIGNED LICENSE AGREEMENT COVERING ITS SUBJECT
MATIER HAS BEEN EXECUTED BETWEEN YOU AND MOTOROLA. BY USING THE PRODUCT, YOU
ACKNOWLEDGE THAT THJS AGREEMENT HAS BEEN READ AND UNDERSTOOD AND THAT YOU
AGREE TO BE BOUND BY ITS TERMS AND CONDillONS . IF YOU DO NOT AGREE, YOU ARE NOT
LICENSED TO USE THE PRODUCT , AND IF YOU ARE THE PURCHASER OF THE PRODUCT, YOU
SHOULD IMMEDIATELY RETURN THE PRODUCT IN ITS ENTIRETY TO ITS PLACE OF PURCHASE FOR
A REFUND.
Motorola grants to You a non- exclusive license to use the SOFTWARE in the manner described in the docu-
mt!ntntion assod;. 1t ed with the produ t. Motorola retai ns ownership of the SO fT WARE including ilU pat · •nt ,
·opy,rights, a nd o lh '!' in te ll ect ual pr pt'r ty ri ght s. You may transfer this licens ~ to u se the SOFT\ t\IA RE as lo ng
as th e tran sferee agrees to be bound by th e t -e n ns of this Agreement.
You agree not to reverse engineer or create derivative works of the SOFTWARE; not to transmit the SOFT-
WARE electronically; not to modify, configure, or use the SOFTWARE in any manner not authorized by
MOTOROLA; and, except as an integral part of the product, not to rent, lease, or convey the SOFIWARE.
MOTOROLA SHALL
NOT BE LIABLE FOR INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
FROM THE USE OF THIS SOFTWARE.
With r sp t t , th· U.S . ovetmm en l, if acqu ir• d under PAR policy (52.-27-19), the SO FT WA RE is pr JVided
with Restricted Right ond i( ncquircd und er DFARS pol i'cy (227.7202), then the SOFI 'WA RE is prov ide Ionly
with th ·omrn . rd 1 rl ~ h ls of this A p, r' 'C menl.
This license is effective until terminated. It will terminate immediately and automatically if You fail to comply
with any term of this Agreement.
You agree that this is the complete and exclusive statement of the agreement between You and Motorola and
that any modification of these terms shall be made only by mutual agreement and evidenced by written
amendment signed by both parties . This Agreement shall be governed and interpreted by the laws of the
State of Illinois, United States of America.
Computer Software Copyrights
This manual may not be reproduced, in whole or in part, in any fmm whatsoever, without the express written per-
mission ofMotorola, Inc.
The Motorola products described in this manual contain one or more computer programs . n1ese computer
programs are protected by copyright law and international treaties. Unauthorized reproduction or distribu-
tion of these programs, or any part thereof, may result in severe civil and criminal penalties, and will be pros-
ecuted to the maximum extent possible under the law . U. S. and international patents pending .
This product Is covered by one or more Issued U.S. Patents. Other Patent applications pending.

Table of Contents
Product Safety and RF Exposure Compliance .. .. ................ . .. vii
Chapter 1 Introduction
1.1 ScopeofManual......................................................................................... .. .... . .. 1-1
1.2 Warranty and Service Support................................................................ .. .. ......... 1-1
1.2.1 Warranty Period ..................................... .... ... .. . .... . .... ... . .. ................... .. .. 1-1
1.2.2 Return Instructions...................................... .. .. .. ................................... .. 1-1
1.2.3 After Warranty Period ..................................... .. ........... .. ...... .. ..... .. ..... .. .. 1-1
1.3 Related Documents .................................. .. ................... ... .. .... ... ...... .. ......... ..... ... .1-2
1.4 Technical Support...................................................... .. ... .................................. ... 1-2
1.5 Warranty and Repairs................................................ ... ... .. ...................... .... .. .. . .. .1-2
1.6 Radio Model Chart and Specifications...................... ........ ... ................................ 1-3
1.7 Radio Modellnformation.............................................
.. .. ................................ .. ... 1-3
Chapter 2 Theory of Operation
2.1 Overview.............................................................................................................. 2-1
2.2 Controller ........................................................ .. .. ........ .. .. ........... .. ............. .... ... .... 2-1
2.2.1 Radio Power Distribution .. ... .... ..... .. .............................. .. .............. .. .. . .. .. 2-2
2.2.2 Automatic On/Off ..........................................
.. .......................................2-3
2.2.3 Emergency.........................................................
.. ........ .. .. . ... ..... .. .... ... .... 2-4
2.2.4 Mechanical On/Off............................................................................
... ..2-4
2.2.5 Ignition .
.. . .. ... ... ........................................................................ ..... . ..... . ... 2-4
2.2.6 Microprocessor Clock Synthesizer.......
.. ..... .. ............... .. ...... .. ....... .. .. ... .. 2-5
2.2.7 Serial Peripheral Interface (SPI) ................
.... ........... .... ................. .. .. .... 2-5
2.2.8 SBEP Serial Interface .........................................
... ................................ 2-6
2.2.9 General Purpose lnpuUOutput
.. .......... .. ...................... ... ...... .. ...... ... ....... 2-6
2.2.1 0 Normal Microprocessor Operation ...................
.. ....... ... ............ .... .. .. ...... 2-7
2.2.11 Static Random Access Memory (SRAM) ......
.. ....... .. .. . .. .........................2-8
2.3 Controller Board Audio and Signalling Circuits
.... ............................. .... ........... .. .. 2-8
2.3.1 Audio Signalling Filter
IC with Compander (ASFIC CMP) ..................... 2-8
2.3.2 Transmit Audio Circuits......................................................
.... .. ............ .. 2-9
2.3.3 Microphone Input Path ............................................
.. . .... ........ .. .... ........ .. 2-9
2.3.3.1 PTT Sensing and TX Audio Processing .
.... .. ....... .. .. ................ 2-10
2.3.3.2 TX Secure Audio (optional) ............................ .. .... . .... .. ............ 2-10
2.3.3.3 Option Board Transmit Audio ........................... .. ........ ........ ..... 2-10
2.3.4 Transmit Signalling Circuits .......................................................... .. ... .. 2-11
2.3.4.1 Sub-Audible Data (PL/DPL) .................................................... 2-11
2.3.4.2 High Speed Data ....................................... ... .. . .. ............. .. ....... 2-12

ii
2.3.4.3 Dual Tone Multiple Frequency (DTMF) Data ........................ ... 2-12
2.3.5 Receive Audio Circuits .........................................................................2-13
2.3.5.1 Squelch Detect.........................................................................2-13
2.3.5.2 Audio Processing and Digital Volume Control .........................2-13
2.3.5.3 Audio Amplification Speaker(+) Speaker(-) ...........................2-14
2.3.5.4 Handset Audio .........................................................................2-14
2.3.5.5 Filtered Audio and Flat Audio...................................................2-15
2.3.5.6 RX Secure Audio Option..........................................................2-15
2.3.5.7 Option Board Receive Audio....................................................2-15
2.3.6 Receive Signalling Circuits...................................................................2-16
2.3.6.1 Sub-Audible Data (PLIDPL) and High Speed Data Decoder
... 2-16
2.3.6.2 Alert Tone Circuits ...................................................................2-16
2.3.6.3 Voice Storage Option...............................................................2-17
2.4 200 MHz Receiver Front-End.............................................................................2-18
2.4.1 Receiver Front End ..............................................................................2-18
2.4.2 Receiver Back End...............................................................................2-19
2.5 Transmitter Power Amplifier (PA)
25 W .............................................................2-19
2.5.1 Power Controlled Stage ......................................
.. ...... .. .......................2-20
2.5.2 Pre-Driver Stage...................................................................................2-20
2.5.3 Final Stage ....................................................................... .. ... ...............2-20
2.5.4 Directional Coupler .. .............................................. .. .... ... ......................2-20
2.5.5 Antenna Switch ....................................................................................2-20
2.5.6 Harmonic Filter .....................................................................................2-21
2.5.7 Power Control.......................................................................................2-21
2.6 Frequency Synthesis..........................................................................................2-21
2.6.1 Reference Oscillator..................................................
.. .........................2-21
2.6.2 Fractionai-N Synthesizer..............................,.......................................2-22
2.6.3 Voltage Controlled Oscillator
(VC0) .....................................................2-23
2.6.4 Synthesizer Operation ..........................................................................2-24
2.7 700 MHz Receiver Front-End.............................................................................2-25
2.7.1 Receiver Front-End .........................
.. ...................................................2-25
2.7.2 Receiver Back-End.............................
... ........................................ ... .... 2-25
2.8 Transmitter Power Amplifier (PA)
15 W .............................................................2-26
2.8.1 Power Controlled Stage ..................................................
.... .................2-26
2.8.2 Driver Stage .........................................................................................2-27
2.8.3 Final Stage .................................. .. .............. ... ................................... .. .2-27
2.8.4 Antenna Switch ....................................................................................2-27
2.8.5 Harmonic Filter
... ........ ... .............. ... ................................... .. .................2-27
2.8.6 Bi-Directional Coupler ..........................................................................2-27
2.8.7 Power Control.......................................................................................2-27
2.9 Frequency Synthesis..........................................................................................2-28
2.9.1 Reference Oscillator.............................................................................2-28
2.9.2 Fractionai-N Synthesizer......................................................................2-28
2.9.3 Voltage Controlled Oscillator
(VC0) .....................................................2-29
2.9.4 Synthesizer Operation..........................................................................2-31
.)

iii
2.10 Control Head (COM1550•LS+) .......................................................................... 2-31
2.1 0.1 Power Supplies ..................................................................... .. ..... ........ 2-31
2.10.2 Power On I Off............................................................................... ... . .. 2-32
2.1 0.3 Microprocessor Circuit ................................. .. .................. .. .................. 2-32
2.10.4 SBEP Seriallnterface................................................... .... ...... ... .......... 2-32
2.1 0.5 Keypad Keys.......................................... ... ........................... .. . ... .. .. ...... 2-33
2.10.6 Status LED
and Back Light Circuit................ .. ...................... .. .. ... ........ 2-33
2.1 0. 7 Liquid Crystal Display (LCD)................................................................ 2-33
2.1 0.8 Microphone Connector Signals........................................................ .. .. 2-34
2.1 0.9 Speaker................................................................................ .. .. ............ 2-35
2.1 0.1 0 Electrostatic Transient Protection .. ....... .. .................... ..... ............ .... .. .. 2-35
2.11 PassPort Trunking Controller Board (PTCB) .. .. . .. ........ .................................... .. 2-35
Chapter 3 Maintenance
3.1 Introduction ...................................................................... .. .................................. 3-1
3.2 Preventive Maintenance .. ... .... ........................ .. ............. ... .. ... ... ........................... 3-1
3.2.1 Inspection................................ ... ............................ .. . .. ........................... 3-1
3.2.2 Cleaning........... .. ................ ... ........... .. ... .. ....... .. ......... .. ......................... .. 3-1
3.3 Safe Handling of CMOS and LDMOS................................ .. .... . .. .. ............. .. ..... .. .3-2
3.4 General Repair Procedures and Techniques ........................ .... ..... .... .. .. .... . .... .. .. 3-2
3.5 Recommended Test Tools.......
.. . ... .......................................................... ... .. .... ... 3-5
3.6 Receiver Troubleshooting Chart (200 MHz) ..............................................
.. .... .... 3-6
3.7 Receiver Troubleshooting Chart (700 MHz) ............ .. .......... .... ........ .. ..... .. .. .. .. ..... 3-8
3.8 Transmitter Troubleshooting Chart (200 MHz) ............................
.. .................. .. 3-10
3.9 Transmitter Troubleshooting Chart (700 MHz) .................................................. 3-11
3.10 Synthesizer Troubleshooting Chart (200 MHz)............ .. ... .. ............................... 3-12
3.11 Synthesizer Troubleshooting Chart (700 MHz)............. .. .. .............. ... ....... .. .. ... .. 3-13
3.12 VCO Troubleshooting Chart (200 MHz)............................................................. 3-15
3.13 VCO Troubleshooting Chart (700 MHz)...................................... .... ..... .. ............ 3-16
Chapter 4 Schematic Diagrams, Overlays,
and Parts Lists
4.1 Introduction....................................... .. ............................................................... .. 4-1
4.1.1 Notes For All Schematics and Circuit Boards........................................ 4-1
Figure 4-1. CDM1550•LS+ Control Head Top Overlay ..................................... .. ... 4-3
Figure 4-2. CDM1550•LS+ Control Head Bottom Overlay ................................. .. .. 4-4
Figure 4-3. CDM1550•LS+ Control Head Schematic Diagram .......
.. ............... .. ..... 4-5
Figure 4-4. CDM1550•LS+ Control Head Keypad Schematic ................................4-6
Figure 4-5. CDM1550•LS+ Control Head Backlight Schematic ... .. ............... .. ........ 4-7
Figure 4-6. CDM1550•LS+ Control Head Display Schematic .....
.. .........................4-8
CDM1550•LS+ Control Head Parts List.......................................................................4-9
Figure 4-7. 200 MHz Main Board Top Side PCB ............................... ... .. .. ............4-11
Figure 4-8.
200 MHz Main Board Bottom Side PCB ................................... .... .. .. .4-12
Figure 4-9. 200 MHz Receiver Front
End Schematic Diagram .............. .. .. .. ........ 4-13

iv
Figure 4-10. 200 MHz Receiver IF Schematic Diagram .............................. .. .... .. ... 4- 14
Figure 4-11. 200 MHz Transmitter Power Amplifier Schematic Diagram ..............4-15
Figure 4-12. 200 MHz Fractionai-N Synthesizer Schematic Diagram ..
.. ......... ... .. .. 4-16
Figure 4-13. 200 MHz Voltage Controlled Oscillator Schematic Diagram ...........
.. .4-17
Figure 4-14. 200 MHz Overall Controller Schematic Diagram ................... .. .... .. .....4-18
Figure 4-15. 200 MHz Microprocessor Schematic Diagram ............
.. .....................4-19
Figure 4-16. 200 MHz Audio Schematic Diagram
.. ........... .... .................... ........ .. .. ..4-20
Figure 4-17. 200 MHz Interface
and Connectors Schematic Diagram .. .. . ... .. ......... 4-21
Figure 4-18. 200 MHz Power Supply Schematic Diagram .. .............................. ...... 4-22
200 MHz Radio Parts List........................... .... ...... .. .... ... ...... .. .... ...... ..... .... .......... ... ... .A-23
Figure 4-19. 700 MHz Main Board Top Side PCB ........ ... ...... .... ........ .. ....... .. ..........4-27
Figure 4-20. 700 MHz Main Board Bottom Side
PCB ............... ... ..... .. ....... .... .........4-28
Figure 4-21. 700 MHz Receiver Front
End Schematic Diagram .. ..... .... ..... .... ..... .. ..4-29
Figure 4-22. 700 MHz Receiver
IF Schematic Diagram ................................ .. . ... ...4-30
Figure 4-23. 700 MHz Transmitter Power Amplifier Schematic Diagram ..........
.... .4-31
Figure 4-24. 700 MHz Fractionai-N Synthesizer Schematic Diagram .. .............. .. .. 4-32
Figure 4-25. 700 MHz Voltage Controlled Oscillator Schematic Diagram
.. ... .. . .. . .. .4-33
Figure 4-26. 700 MHz Overall Controller Schematic Diagram
... ...................... .. ... .. 4-34
Figure 4-27. 700 MHz Microprocessor Schematic Diagram ........
.. ....................... .. 4-35
Figure 4-28. 700 MHz Audio Schematic Diagram .................
... ...................... .. .......4-36
Figure 4-29. 700 MHz Interface
and Connectors Schematic Diagram ...... .. ... ........4-37
Figure 4-30. 700 MHz Power Supply Schematic Diagram
.. ..................... .... .. ...... .. .4-38
700 MHz Radio Parts List.................................................... .... ....... .. ..........................4-39
Figure 4-31. PassPort Trunking Controller Board Side 1 &2
... .... ..........................4-45
Figure 4-32. PassPort Trunking Controller Board Schematic Diagram ..................4-46
_)

v
List of Figures
Figure 2-1.
Figure 2-2.
Figure 2-3.
Figure 2-4.
Figure 2-5.
Figure 2-6.
Figure 2-7.
Figure 2-8.
Figure 2-9.
Figure 2-10.
Figure 2-11.
Figure 2-12.
Figure 2-13.
Figure 2-14.
Figure 4-1.
Figure 4-2.
Figure 4-3.
Figure 4-4.
Figure 4-5.
Figure 4-6.
Figure 4-7.
Figure 4-8.
Figure 4-9.
Figure 4-10.
Figure 4-11.
Figure 4-12.
Figure 4-13.
Figure 4-14.
Figure 4-15.
Figure 4-16.
Figure 4-17.
Figure 4-18.
Figure 4-19.
Figure 4-20.
Figure 4-21.
Figure 4-22.
Figure 4-23.
Figure 4-24.
Figure 4-25.
Figure 4-26.
Figure 4-27.
Figure 4-28.
Figure 4-29.
Figure 4-30.
Figure 4-31.
Figure 4-32.
Controller Block Diagram.................... .. .. .................... .. ........................... 2-1
DC Power Distribution Block Diagram .......... ... ......... .. ....... .. ... ................. 2-3
Transmit Audio Paths .................................
.. ...... ... .. ................................ 2-9
Transmit Signalling Paths...........................
.. ......................................... 2-11
Receive Audio Paths .......................................
.. ................... ... .............. 2-13
Receive Signalling Paths....................
.... .. ........... ... ............................... 2-16
200 MHz Receiver Block Diagram..... .. .... .............................................. 2-18
200 MHz Transmitter Block Diagram..................................................... 2-19
200 MHz Synthesizer Block Diagram .................................................... 2-22
200 MHz VCO Block Diagram ............................................................... 2-23
700 MHz Receiver Block Diagram.............................................. .. ......... 2-25
700 MHz Transmitter Block Diagram..................................................... 2-26
700 MHz Synthesizer Block Diagram .................................................... 2-29
700 MHz VCO Block Diagram ............................................................... 2-30
CDM1550•LS+ Control Head Top Overlay.............................................. 4-3
COM1550•LS+ Control Head Bottom Overlay......................................... 4-4
CDM1550•LS+ Control Head Schematic Diagram ........... .. ........ .... ....... .. 4-5
COM1550•LS+ Control Head Keypad Schematic
.. ..... .. .. .... ... .... .. ......... .. 4-6
CDM1550•LS+ Control Head Backlight Schematic ... ............. ... .............. 4-7
CDM1550•LS+ Control Head Display Schematic.................................... 4-8
200 MHz Main Board Top Side PCB ...................... .. ............................. 4-11
200 MHz Main Board Bottom Side PCB............................. .. .............. ... 4-12
200 MHz Receiver Front End Schematic Diagram ...... .. .. ......... .. ........... 4-13
200 MHz Receiver IF Schematic Diagram ............................................ 4-14
200 MHz Transmitter Power Amplifier Schematic Diagram .. .. ............. 4-15
200 MHz Fractionai-N Synthesizer Schematic Diagram .... .. ............. .. .. 4-16
200 MHz Voltage Controlled Oscillator Schematic Diagram .... ... .... .. .... 4-17
200 MHz Overall Controller Schematic Diagram ............... .. .. .. . ... .......... 4-18
200 MHz Microprocessor Schematic Diagram ..................... .. . ... ...... .. ... 4-19
200 MHz Audio Schematic Diagram................................. ... .................. 4-20
200 MHz Interface and Connectors Schematic Diagram .
... .... .. ............ 4-21
200 MHz Power Supply Schematic Diagram .. ................................. .. .. .. 4-22
700 MHz Main Board Top Side PCB .......................... .. ........... .. ...... ... ... 4-27
700 MHz Main Board Bottom Side PCB ................................................ 4-28
700 MHz Receiver Front End Schematic Diagram .................... .. ... .. .. ... 4-29
700 MHz Receiver IF Schematic Diagram .......................................... .. 4-30
700 MHz Transmitter Power Amplifier Schematic Diagram ......
.. ........ .. 4-31
700 MHz Fractionai-N Synthesizer Schematic Diagram ...... .. ......... .. .. .. 4-32
700 MHz Voltage Controlled Oscillator Schematic Diagram ................. 4-33
700 MHz Overall Controller Schematic Diagram ............ .. ..................... 4-34
700 MHz Microprocessor Schematic Diagram .. .............. .. ...... .. ............ 4-35
700 MHz Audio Schematic Diagram................... .. ............................... .. 4-36
700 MHz Interface and Connectors Schematic Diagram .. .... ... .... .. ... .... 4-37
700 MHz Power Supply Schematic Diagram ... ...................................... 4-38
PassPort Trunking Controller Board Side 1 &2 ...............
.. ....... ... .. ....... 4-45
PassPort Trunking Controller Board Schematic Diagram ..................... 4-46

vi
List of Tables
Table 1-1.
Table 1-2.
Table 3-1.
Related Documents.................................................................................. 1-2
Radio Model Number............................................................................... 1-3
Recommended Test Tools...
.. ......... .. . .. ...... .. .. ... ... ..... .. . .. ... .. ....... .. ......... .. . 3-5
)

Safety-vii
PRODUCT SAFETY AND RF EXPOSURE COMPLIANCE
Caution
Before using this product, read the operating instructions for safe usage contained in the
Product Safety and RF Exposure booklet enclosed with your radio.
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
68P81095C99) 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.·

Safety-viii
This page intentionally left blank