Motorola Radio Mcs2000 Vol 1 68p81083c20 A Manual

							 
Disassembly & Reassembly and Replacement Procedures 5-5 
3. Carefully remove the transceiver board by rotating it out of the chassis. 
Slowly lift the board on the front edge while pushing up on the board 
through the accessory connector opening. Pull the board forward out of 
the chassis.  
M 
ID 
 P 
OWER 
 M 
ODELS 
1. Remove the Accessory Connector by sliding a Þnger into the recess on 
the chassis and pushing up on the connector tab to loosen the 
connection. Lift the connector out of the recess.
2. Remove the power and antenna connector retaining clips by inserting a 
small ßat-blade screwdriver or like instrument between the clip and the 
top of the cavity wall per area shown inFigure 5-6. Gently prying 
upwards.
3. Remove the PCB Clip and the Audio PA clip by inserting a ßat-blace 
screwdriver or like instrument between the clip and the side wall. Prying 
the clip upward to disengage with the tabs on the wall.
4. Remove the four recessed Power AmpliÞer Device screws using a T-8 Torx 
Driver (see Figure 5-7).
5. Remove the remaining screws with a T-10 Torx Driver.
6. Carefully remove the transceiver board by rotating it out of the chassis. 
Slowly lift the board on the front edge while pushing up on the board 
through the accessory connector opening. Pull the board forward out of 
the chassis.
Thermal Grease can act as an adhesive and cause the leads 
of the power ampliÞer devices to be over stressed if the 
board is lifted too quickly. 
Figure 5-7   Removing the Transceiver Board - Mid Power Models 
(except 800 MHz and 900 MHz)
Note
PCB Mount Clip Power Connector
Clip
Antenna Connector
ClipFour Recessed Power
AmpliÞer Screws
Audio PA Clip 
						

							 
5-6 Disassembly & Reassembly and Replacement Procedures 
Remove the 
Transceiver Board 
800 MH 
Z 
  
AND 
 900 MH 
Z 
 
M 
ODELS 
 O 
NLY 
1. Remove the Accessory Connector by sliding a Þnger into the recess on 
the chassis and pushing up on the connector tab to loosen the 
connection. Lift the connector out of the recess.
2. Remove all screws using a T-10 TORX driver.
3. Remove the power and antenna connector retaining clips by inserting a 
small ßat blade screwdriver between the clip and the top of the cavity 
wall and gently prying the clip upwards. 
On Mid Power models 
: Remove the PCB clip and the Audio PA clip by 
inserting a ßat-blace screwdriver or like instrument between the clip and 
the side wall. Prying the clip upward to disengage with the tabs on the 
wall.
4. Press on the 25 pin connector through the bottom of the chassis until 
the board is released from the chassis.
5. Carefully remove the transceiver board by rotating it out of the chassis. 
Slowly lift the board on the front edge while pushing up on the board 
through the accessory connector opening (see Figure 5-8). 
Figure 5-8   Removing the Transceiver Board (800 MHz and 900 MHz only)
Board Holding Screw
(To be removed last)
PA Holding Screws (2)
Antenna Connector
Retaining ClipPower Connector
Retaining Clip Front 
						

							 
Disassembly & Reassembly and Replacement Procedures 5-7 
Disassembly to Transceiver Board Level
High Power Models 
DO NOT attempt to disassemble the radio without Þrst referring to the 
CMOS Precautions paragraph on page 2-2 in the Maintenance section. 
Remove the 
Bottom Cover 
1. Disconnect the Remote Mount Cable by squeezing the top and bottom 
of the connector together, disengaging the bottom snap then the top, 
and pulling straight out.
2. Flip the unit over so that the Bottom Cover is facing up. 
Figure 5-9    Direction Conventions 
3. Remove the Accessory Connector by sliding a Þnger into the recess on 
the bottom cover and pushing up on the connector tab to loosen the 
connection. Lift the connector out of the recess. See Figure 5-10. 
Figure 5-10    Removing the Accessory Connector
!
C a u t i o n
To p
FrontBottomBack
Accessory Connector Bottom Cover
1) Slide Þnger 
    under tab2) Pull connector
     straight out 
						

							 
5-8 Disassembly & Reassembly and Replacement Procedures 
4. Insert a wide ßat-blade screwdriver or like instrument in the recess area 
on the side of the radio near the antenna and power connector ends (see 
Figure 5-11).
5. Pry the bottom cover off the chassis by pushing the handle of a 
screwdriver up and toward the radio. This will disengage the snap 
between the bottom cover and the chassis.
6. Repeat Step 4. and Step 5. for the other side of the radio.
7. Rotate the bottom cover out and away from the chassis until it is 
completely free of the chassis taking care not to damage the 18 position 
connector in the process. 
Figure 5-11    Removing the Bottom Cover 
8. Remove the cover gasket from the chassis. 
Remove the RF 
Shield 
1. Pull straight up on the RF shield using the supplied handle. 
Figure 5-12   Removing the RF Shield
Disengage Snap here
and on other side
18 Position Connector Rotate Cover
in this Direction Out and Away 
RF Shield
Handle 
						

							 
Disassembly & Reassembly and Replacement Procedures 5-9 
Remove the PA 
Shield 
1. Pull straight up on the PA shield using the supplied handle. 
Figure 5-13    Removing the PA Shield 
Remove the PA 
Board 
1. Unscrew the 6 recessed, PA device screws using a T-8 Torx driver. 
Unscrew the remaining screws (9 for VHF, 11 for UHF) using a T-10 Torx 
driver.
2. Remove the power and antenna connector retaining clips by inserting a 
small ßat-blade screwdriver between the clip and the underlying cavity 
wall and by gently prying the clip upwards.
3. Gently disconnect the 2 and 12 position connectors from the RF board 
by rotating the PA Board toward the chassis Þns.
4. Once the connectors are disengaged, remove the PA Board from the 
chassis by pulling edge of board up and away from Þn (back) side of 
radio. 
Figure 5-14    Removing the PA Board
PA Shield
Handle
Pry Clip off here Pry Clip off here
Disconnect PA board
from these two RF 
connectors 
						

							 
5-10 Disassembly & Reassembly and Replacement Procedures 
Remove the RF 
Board 
1. Remove the 18 position connector by pulling it straight out from the 
chassis taking care not the bend the leads.
2. Remove the Audio PA Clip by inserting a ßat-blade screwdriver under the 
clip«s extended tab, pivoting off the top of the underlying wall, and 
gently prying the clip upward.
3. Unscrew the 7 screws that hold the RF board in place using a T-10 Torx 
driver.
4. Carefully remove the RF board from the chassis by pulling straight up on 
the 25 D connector. 
Figure 5-15    Removing the RF Board
Pry off Audio PA clip here
18 Position Connector 25 D Connector
Pull Connector 
straight outPull Board 
straight up 
						

							 
Disassembly & Reassembly and Replacement Procedures 5-11 
Disassembly of the Control Head 
Remote Mount 
Versions 
1. Disconnect the Remote Mount Cable by squeezing the top and bottom 
of the connector together, disengaging the bottom snap then the top, 
and pulling straight out.
2. Remove the back housing by inserting a small ßat-blade screwdriver or 
like instrument into the recess on the short side of the control head 
exterior, taking care not to mar the surface. Rotate the screwdriver so 
that the tab deßects out and disengages from the control head housing.
3. Repeat the operation in Step 2. for the opposite side. 
Model I 
1. Remove the internal spacer by inserting a small ßat-blade screwdriver or 
like instrument into one of the eight recesses around the perimeter of 
the spacer. Rotate the screwdriver so that the spacer deßects in and the 
tab disengages from the control head housing.
2. Repeat Step 1. for the remaining seven recesses. 
3. Pull the control head board straight out from the control head housing, 
removing the control head board, the speaker, and the keypad together.
4. Remove the keypad from the PCB by pulling up on the keypad. Care is 
required in removing the keypad from around the volume 
potentiometer and the microphone connector to keep from 
overstressing the leads. Care should be taken not to touch or get other 
contaminants on the conductive pads on the underside of the keypad.
5. To remove the LCD gasket, Þrst remove the elastomeric connector, the 
LCD frame, the colour sheet and the LCD itself from the housing.
6. Disconnect the speaker lead from the connector on the control head 
board. 
Models II & III 
S 
TANDARD 
 K 
EYPAD 
1. Pull the back housing straight off.
2. 
On Model II 
, also remove the rotary knob on the right side of the unit 
by pulling away from the control head.
3. Remove the control head board by prying back on the four visible light 
pipe snaps. Carefully remove the board from the housing. Gently pull 
the board straight up so not to damage the volume potentiometer and 
the microphone connector leads.
4. The light pipe can be removed by prying back on its plastic snaps from 
the recesses in the control head housing. This step is only required to 
gain access to the keypad.
5. With the light pipe removed, the keypad can be pulled from the 
housing. Care should be taken not to touch or get other contaminants 
on the conductive pads on the under side of the keypad. 
Models II & III 
K 
EYPAD 
  
WITH 
 
R 
EPLACEABLE 
 P 
USH 
 
B 
UTTONS 
1. Remove the back housing by inserting a small ßat-blade screwdriver or 
like instrument into the recess on the short side of the control head 
exterior, taking care not to mar the surface. Rotate the screwdriver so 
that the tab deßects out and disengages from the control head housing.
2. Repeat the operation in Step 1. for the opposite side.
3. Pull the back housing straight off. 
						

							 
5-12 Disassembly & Reassembly and Replacement Procedures 
4. 
On Model II 
, also remove the rotary knob on the right side of the unit 
by pulling straight up.
5. Remove the control head board by prying back on the four visible light 
pipe snaps. Carefully remove the board from the housing. Gently pull 
the board straight up so not to damage the volume potentiometer and 
the microphone connector leads.
6. The light pipe can be removed by prying back on its plastic snaps from 
the recesses in the control head housing. This step is only required to 
gain access to the keypad.
Care should be taken when removing the light pipe from control heads 
equipped with replaceable pushbuttons as the buttons are loose in the housing 
under the keypad.
7. With the light pipe removed, the keypad can be pulled from the 
housing. Care should be taken not to touch or get other contaminants 
on the conductive pads on the underside of the keypad.
Note 
						

							 
Disassembly & Reassembly and Replacement Procedures 5-13 
Reassembly
 of the Control Head 
Model I1. Place the LCD, colour sheet, LCD frame, and elastomeric connector into 
the housing. Make sure that the LCD aligns with the gasket in the 
housing.
2. Place the keypad into the board assembly, making sure that the keypad is 
ßush with the board.
3. Make sure that both the volume knob and potentiometer are both fully 
in the counter clockwise position before assembling the board into the 
housing.
4. Also make sure that the speaker is aligned with the speaker gasket and 
connected to the board assembly.
5. During the installation of the internal speaker be sure that all eight snaps 
are engaged. Be sure not to crimp the speaker wire.
Models II and III1. Place the keypad into the control head housing.
2. Snap the light pipe into the housing. Alternate engaging snaps on each 
side for best result.
3. Make sure that both the volume knob and potentiometer are both fully 
in the counter clockwise position before assembling the board into the 
housing.
4. Snap the board assembly into the housing.
5. For model ÒIIÓ only, attach the large rotary knob. 
						

							5-14 Disassembly & Reassembly and Replacement Procedures
Transceiver Reassembly
Low and Mid Power Models
Transceiver Reassembly
¥ Replace all gaskets at each servicing to ensure proper sealing of unit.
¥ Be careful to use only very little thermal grease as an excessive quantity 
will deteriorate the conductivity.
1. Inspect and reapply thermal grease as needed to the areas shown in 
Figure 5-16.
Figure 5-16    Reassembly
2. Insert the diode spring. 
3. Install a new gasket to the 25 pin connector, Antenna connector and 
Power connector gaskets located on the board.
4.On 800/900 MHz Models only: Insert board slot shield.
5. Replace the thermal pad attached to the large heatsink (designator 
B6501) on the bottom side of the board in the PA section.
6. Insert the main board carefully at an appropriate angle (approximately 
30°) into the chassis.
7. Install the antenna and power connector retaining clips.
8.On Low Power Models Only: Install all screws (except the three screws 
that retain the PA shield) with 12 in lbs of torque using a T-10 Torx 
driver.
On Mid Power 800/900 MHz Models: Install all screws (except the 
three screws that retain the PA shield) with 12 in lbs of torque using a T-
10 Torx driver.
On Mid Power Models (Excluding 800/900 MHz): Install the four 
screws in the recessed PA devices with 12 in lbs of torque using a T-8 Torx Notes
Audio PA and Regulator Pedestals
Board Slot Shield
Diode Spring
Chassis PA Pedestal
Apply Thermal Grease
to this raised surface Apply Thermal Grease
to these raised surfaces