Motorola Cdm Series Basic 6881091c62 D Manual

CDM Series™
Professional Series
Two-Way Mobile Radio
Basic Service Manual 

 CDM Series™
Professional Series
Two-Way Mobile Radio
Basic Service Manual
Motorola, Inc.
8000 West Sunrise Boulevard
Fort Lauderdale, Florida 33322
6881091C62-D 

ii
Foreword
This manual provides sufficient information to enable qualified service technicians to troubleshoot and repair 
CDM Series mobile radios to the component level.
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 (Motorola Publication part number...

iii
Table of Contents
Foreword .........................................................................................................ii
Product Safety and RF Exposure Compliance ............................................................... ii
Computer Software Copyrights....................................................................................... ii
Document Copyrights ..................................................................................................... ii
Disclaimer...

iv
2.6.5 CDM1250, CDM1550, CDM1550•LS, and CDM1550•LS+ Control Head 
Disassembly ..............................................................................................2-9
2.7 Radio Assembly ................................................................................................ 2-10
2.7.1 CDM750 Control Head ............................................................................2-10
2.7.2 CDM1250, CDM1550, CDM1550•LS, and CDM1550•LS+ 
Control Heads...

v
4.4.5 Power Amplifier (PA) Voltage Limit Tuning (VHF 1-25W and UHF 1-25W 
LDMOS radios only).................................................................................. 4-7
4.4.6 Modulation Balance Attenuation ............................................................... 4-8
4.4.7 VCO Attenuation ....................................................................................... 4-9
4.4.8 VCO Attenuation (25 kHz) ........................................................................ 4-9...

vi
Chapter 7
Model Chart and Test Specifications ....................................................... 7-1
7.1 UHF 403-470 MHz (Conventional) ...................................................................... 7-1
7.2 UHF 450-512 MHz (Conventional) ...................................................................... 7-2
7.3 UHF 403-470 MHz (Conventional, LTR) ............................................................. 7-3
7.4 UHF 450-512 MHz (Conventional, LTR)...

1-1
Chapter 1
Introduction
1.1 Scope of Manual
This manual is intended for use by service technicians familiar with similar types of equipment. It 
contains service information required for the equipment described in this document and is current as 
of the printing date. Changes which occur after the printing date will be incorporated in a complete 
Manual Revision or alternatively as additions.
1.2 Warranty and Service Support
Motorola offers support which includes: full exchange and/or repair of the...

1-2Introduction
1.2.3 Piece Parts Availability
Some replacement parts, spare parts, and/or product information can be ordered directly.
Motorola Online:
Motorola Online users can access our online catalog at
https://www.motorola.com/businessonline
To register for online access, please call 800-814-0601.
Mail Orders:
Send written orders to the following addresses:
Telephone Orders
Customer Care and Services Division*
7:00 AM to 7:00 PM (Central Standard Time)
Monday through Friday (Chicago, U.S.A.)...