Motorola Cm Radio Basic Manual

							Warranty and Service Support1-3
2.5 Technical Support
Motorola Product Services is available to assist the dealer/distributors in resolving any malfunctions 
which may be encountered.
UK/Ireland - Richard Russell
Telephone:  +44 (0) 1256 488 082
Fax:  +44 01256 488 080
Email:  [email protected]
Central/East Europe- Siggy Punzenberger
Telephone:  +49 (0) 6128 70 2342
Fax:  +49 (0) 6128 95 1096
Email:  [email protected]
Scandinavia
Telephone:  +46 8 735 9282
Fax:  +46 8 735 9280
Email: [email protected]
Germany -Customer Connect Team
Telephone:  +49 (0) 6128 70 2248
Fax:  +49 (0) 6128 95 1082
Email:  [email protected]
France - Lionel Lhermitte
Telephone:  +33 1 6929 5722
Fax:  +33 1 6929 5904
Email:  [email protected]
Italy - Ugo Gentile
Telephone:  +39 0 2822 0325
Fax:  +39 0 2822 0334
Email:  [email protected]
Africa & Middle East -Armand Roy
Telephone: +33 1 6929 5715
Fax: +33 1 6929 5778
Email: [email protected] 
						

							1-4INTRODUCTION
3.0 Radio Model Information
The model number and serial number are located on a label attached to the back of your radio. You 
can determine the RF output power, frequency band, protocols, and physical packages. The 
example below shows one mobile radio model number and its specific characteristics.
Ta b l e 1 - 1Radio Model Number (Example: MDM50FNC9AN2_N)
Type of
UnitModel
SeriesFreq.
BandPower
LevelPhysical
PackagesChannel
SpacingProtocolFeature
LevelModel
RevisionModel
Package
MD M 50 F
Midband
(66-
88MHz)
J
VHF
(136-
162MHz)
K
VHF
(142-
174MHz)N
1-25WC
CM140
CM3409
Program-
mableAA
Conven-
tional
MDC1
RF 
Connector : 
Mini-UHF AN
Q
UHF1
(403-
430MHz)P
25-40WF
CM160
CM360AN
5 Tone2
RF 
Connector : 
BNC 
R
UHF2
(438-
470MHz)Q
25-45W
S
UHF3
(465-
495MHz)
 MD = Motorola Internal Use
M = Mobile 
						

							Chapter 2
MAINTENANCE
1.0 Introduction
This chapter provides details about the following:
❑Preventive maintenance (inspection and cleaning).
❑Safe handling of CMOS and LDMOS devices.
❑Disassembly and reassembly of the radio.
❑Repair procedures and techniques.
❑Installation of Option Boards.
2.0 Preventive Maintenance
The radios do not require a scheduled preventive maintenance program; however, periodic visual 
inspection and cleaning is recommended.
2.1 Inspection
Check that the external surfaces of the radio are clean, and that all external controls and switches 
are functional. It is not recommended to inspect the interior electronic circuitry.
2.2 Cleaning Procedures
The following procedures describe the recommended cleaning agents and the methods to be used 
when cleaning the external and internal surfaces of the radio. External surfaces include the front 
cover and housing assembly. These surfaces should be cleaned whenever a periodic visual 
inspection reveals the presence of smudges, grease, and/or grime. 
The only recommended agent for cleaning the external radio surfaces is a 0.5% solution of a mild 
dishwashing detergent in water. The only factory recommended liquid for cleaning the printed circuit 
boards and their components is isopropyl alcohol (70% by volume).
Cleaning External Plastic Surfaces
Apply the 0.5% detergent-water solution sparingly with a stiff, non-metallic, short-bristled brush to 
work all loose dirt away from the radio. Use a soft, absorbent, lintless cloth or tissue to remove the 
solution and dry the radio. Make sure that no water remains entrapped near the connectors, cracks, 
or crevices.
NOTEInternal surfaces should be cleaned only when the radio is disassembled for service or
repair.
CAUTION: The effects of certain chemicals and their vapors can have harmful results on
certain plastics. Avoid using aerosol sprays, tuner cleaners, and other chemicals.
! 
						

							2-2MAINTENANCE
Cleaning Internal Circuit Boards and Components
Isopropyl alcohol (100%) may be applied with a stiff, non-metallic, short-bristled brush to dislodge 
embedded or caked materials located in hard-to-reach areas. The brush stroke should direct the 
dislodged material out and away from the inside of the radio. Make sure that controls are not soaked 
with alcohol. Do not use high-pressure air to hasten the drying process since this could cause the 
liquid to collect in unwanted places. After completing of the cleaning process, use a soft, absorbent, 
lintless cloth to dry the area. Do not brush or apply any isopropyl alcohol to the frame, front cover, or 
top cover.
3.0 Safe Handling of CMOS and LDMOS Devices
Complementary metal-oxide semiconductor (CMOS) devices are used in this family of radios, and 
are susceptible to damage by electrostatic or high voltage charges. Damage can be latent, resulting 
in failures occurring weeks or months later. Therefore, special precautions must be taken to prevent 
device damage during disassembly, troubleshooting, and repair. 
Handling precautions are mandatory for CMOS circuits and are especially important in low humidity 
conditions. DO NOT attempt to disassemble the radio without first referring to the following 
CAUTION statement.
NOTEAlways use a fresh supply of alcohol and a clean container to prevent contamination by 
dissolved material (from previous usage).
CAUTION: This radio contains static-sensitive devices. Do not open the radio unless you are
properly grounded. Take the following precautions when working on this unit:
❑Store and transport all CMOS devices in conductive material so that all exposed 
leads are shorted together. Do not insert CMOS devices into conventional plastic 
“snow” trays used for storage and transportation of other semiconductor devices.
❑Ground the working surface of the service bench to protect the CMOS device. We 
recommend using the Motorola Static Protection Assembly (part number 
0180386A82), which includes a wrist strap, two ground cords, a table mat, and a 
floor mat.
❑Wear a conductive wrist strap in series with a 100k resistor to ground. 
(Replacement wrist straps that connect to the bench top covering are Motorola part 
number 4280385A59)
❑Do not wear nylon clothing while handling CMOS devices.
❑Do not insert or remove CMOS devices with power applied. Check all power 
supplies used for testing CMOS devices to be certain that there are no voltage 
transients present.
❑When straightening CMOS pins, provide ground straps for the apparatus used.
❑When soldering, use a grounded soldering iron.
❑If at all possible, handle CMOS devices by the package and not by the leads. Prior to 
touching the unit, touch an electrical ground to remove any static charge that you 
may have accumulated. The package and substrate may be electrically common. If 
so, the reaction of a discharge to the case would cause the same damage as 
touching the leads.
! 
						

							Repair Procedures and Techniques — General 2-3
4.0 Repair Procedures and Techniques — General
Parts Replacement and Substitution
When damaged parts are replaced, identical parts should be used. If the identical replacement part 
is not locally available, check the parts list for the proper Motorola part number and order the part 
from the nearest Motorola Parts centre listed in the “Piece Parts” section in Chapter 1 of this manual.
Rigid Circuit Boards
This family of radios uses bonded, multi-layer, printed circuit boards. Since the inner layers are not 
accessible, some special considerations are required when soldering and unsoldering components. 
The printed-through holes may interconnect multiple layers of the printed circuit. Therefore, exercise 
care to avoid pulling the plated circuit out of the hole.
When soldering near the RF connector, potentiometer, 16-pin and 20-pin connectors:
❑Avoid accidentally getting solder in the connector.
❑Be careful not to form solder bridges between the connector pins.
❑Examine your work closely for shorts due to solder bridges.
5.0 Disassembling and Reassembling the Radio — General
Since these radios may be disassembled and reassembled with the use of only 14 (board to casting) 
screws, it is important to pay particular attention to the snaps and tabs, and how parts align with 
each other.
The following tools are required for disassembling/assembling the radio:
❑Small flat blade screwdriver
❑Phillips small 1# screwdriver
❑TORX™ T9 screwdriver
❑TORX™ T10 screwdriver
❑Torque screwdriver set
❑Torque spanner
If a unit requires more complete testing or service than is customarily performed at the basic level, 
send this unit to a Motorola Authorized Service Centre. (See Chapter 1 for a list of authorized 
service centres.)
The following disassembly procedures should be performed only if necessary: 
						

							2-4MAINTENANCE
6.0 Radio Disassembly - Detailed
The procedure to remove and replace a Control Head, Top Cover or Transceiver Board is similar for 
all models of radio. A typical procedure is therefore shown followed by specific disassembly 
procedures for Control Heads on radio models without a display and radio models fitted with a 
display.
6.1 Control Head Removal
Volume Knob Removal
1. Insert the flat screwdriver between the control head plastic and the volume knob and push the 
volume knob upwards. See Figure 2-1.
Figure 2-1Volume Knob Removal.
2. Insert the flat screw driver (4 mm maximum) into the slot and push the plastic up. 
Do the same with the second slot to free the control head from the chassis assembly. See 
Figure 2-2.
NOTEEnsure that the volume knob is in the OFF position before disassembling the radio. 
						

							Radio Disassembly - Detailed2-5
Figure 2-2Control Head Removal
3. To free the head, disconnect the flat cable from the chassis assembly See Figure 2-3.
Figure 2-3Flat Cable Removal 
						

							2-6MAINTENANCE
6.2 Top Cover Removal
1. Place the radio in a vertical position as shown in Figure 2-4..
Figure 2-4Top Cover Removal (Chassis Vertical).
2. Insert the flat screw driver near the ‘T’ and push the plastic cover up until it pops over the ‘T’ 
mount boss. Perform the same function on the ‘T’ location on the other side of the chassis.
3. Next place the radio in a horizontal position as shown in Figure 2-5 and insert the flat screw 
driver into the slot to release the upper cover.
Figure 2-5Top Cover Removal (Chassis Horizontal) 
						

							Radio Disassembly - Detailed2-7
6.3 Main Shield Removal
1. Insert the screw driver in the gap between the main shield and chassis (speaker cutout area) 
and push the shield up. See Figure 2-6.
2. Lift the cover from the chassis.
Figure 2-6Main Shield Removal
6.4 PA Shield and DC Cable Removal
1. Remove the three screws that attach the PA shield to PCB, and remove the PA shield.
2. Remove the accessory Connector cap.
3. Remove the two screws that attach the DC power cable to the PCB and pull it out from the 
side.
Figure 2-7PA Shield and DC Cable Removal
PA  S h i e l d
Fixing Screws (3)
Accessory 
Connector
CapDC
Cable
DC Cable
Fixing Screws
(2) 
						

							2-8MAINTENANCE
6.5 PAClipandMainPCBRemoval
1. Remove the screw that attaches the PA clip to the chassis. See Figure 2-8.
2. Remove the PA clip.
3. Remove all the screws that fix the PCB to the chassis.
4. Loosen the M1.6 screw (about 3 to 4 turns) on the RF connector.
5. Loosening this screw, enables you to unscrew the RF connector from outside.
6. Carefully remove the main PCB in a diagonal manner.
Figure 2-8PA Clip and Main PCB Removal
NOTEIt is recommended to grip the volume potentiometer and remove the PCB board
M1.6 ScrewPA  C l i p
Main PCB