Table of Contents
Advertisement
3. Disconnect interconnecting cables between the audio
amplifier board and the system board.
TO REMOVE THE LOGIC BOARD A1
1. Remove the top and bottom covers, Front Cap Assem-
bly, Audio Amplifier Board, and the Audio Board from
the radio. Refer to the disassembly for each, in this
section.
2. Remove interconnect plug P702 from the RF and Logic
Boards on the bottom of the radio.
3. Remove the four M3.5-0.6 x 8 TORX screws (#15 drive)
securing the Logic Board to the radio frame.
4. Gently work the Logic Board out of the radio, being
careful not to damage the plug going to the Front Cap
Assembly.
TO REMOVE THE DUPLEXER
INTERFACE BOARD A4
l.
Remove the top cover of the radio.
2. Disconnect the cables going back to the RF Board.
3. Disconnect the cables from the duplexer or talk-around
board.
4. Remove the four M3.5-0.6 TORX screws (#15 drive)
securing the board to the frame. Carefully work the
board out of the radio, unplugging it from the feed
through assembly Z903.
TO REMOVE THE SYSTEM BOARD A5
1. Remove the bottom cover of the radio.
2. Disconnect the ribbon cable from J902.
3. Disconnect the option cable if used.
4. Remove the three M3.5-0.6 x 8 TORX screws (#15
drive) securing the system board to the frame.
5. Carefully work the board out of the radio, unplugging it
from feed through assembly Z903.
CHIP COMPONENT
REPLACEMENT
The procedure for removing chip components is given
below. Replacement procedures for other unique compo-
nents are found in the related board instruction manual where
the component is used (PA module replacement is located in
the RF Board manual).
Replacement of chip capacitors should always be done
with a temperature controlled soldering iron, operating at
700°F (371°C). However, DO NOT touch black metal film
of the resistors or the ceramic body of capacitors with the
soldering iron. NOTE: The metallized end terminations of
the parts may be touched with the soldering iron without
causing damage.
CAUTION
The CMOS Integrated Circuit devices
used in this equipment can be de-
stroyed by static discharges. Before
handling one of these devices, the
serviceman should discharge himself
by touching the case of a bench instrument that has
a 3-prong power cord connected to an outlet with a
known good earth ground. When soldering or
desoldering a CMOS device, the soldering iron
should also have a 3-prong power cord connected
to an outlet with a known good earth ground. A
battery-operated soldering iron may be used in
place of the regular soldering iron.
TO REMOVE CHIP COMPONENTS
l.
Using two soldering irons simultaneously heat each end
of the chip until solder flows, and then remove and
discard the chip.
2. Remove excess solder with a vacuum solder extractor.
3. Carefully remove the epoxy adhesive and excess flux to
prevent damage to the printed board.
TO REPLACE CHIP COMPONENTS
1. Using as little solder as possible, "tin" one end of the
component and one of the pads on the printed wiring
board.
LBI-38953
5
Advertisement
Table of Contents
