1-8 (No.MB269)
3.8
Removing the power amplifier board
(See Fig.10)
• Prior to performing the following procedures, remove the top
cover.
(1) From the top side of the main body, remove the tie bands
fixing the wires.
(2) Remove the tie band and wire protection board fixing the
card wire.
(3) Remove the solders from the soldered section
b
on the
speaker terminal board attaching the parallel wires.
(4) Disconnect the relay board from the connectors (
CN291
,
CN491
) on the main board and front board.
(5) Disconnect the parallel wire from the connector
CN241
on
the main board.
(6) Disconnect the wire from the connector
CN251
on the pow-
er transformer board 1.
(7) Disconnect the wires from the connectors (
CN471
,
CN472
,
CN473
) on the front board.
(8) Remove the screw
J
, two screws
K
and four screws
L
at-
taching the power amplifier board.
(9) Take out the power amplifier board from the main body.
Fig.10
3.9
Removing the heat sink
(See Figs.11 and 12)
• Prior to performing the following procedures, remove the top
cover and power amplifier board.
(1) Remove the three screws
M
attaching the heat sink. (See
Fig.11)
(2) From the reverse side of the power amplifier board, remove
the two screws
N
attaching the heat sink. (See Fig.12)
3.10 Removing the power ICs
(See Figs.12)
• Prior to performing the following procedures, remove the top
cover, power amplifier board and heat sink.
(1) From the reverse side of the power amplifier board, remove
the solders from the soldered sections
c
on the power am-
plifier board.
(2) Remove the power ICs from the forward side of the power
amplifier board.
Fig.11
Fig.12
Soldered section
b
CN471
CN472
CN491
Front
board
CN473
Card
wire
K
L
Tie
band
Wire
protection
board
L
Tie bands
Power amplifier board
Relay board
L
CN241 Main board
CN251
Tie band
CN291
Power
transformer
board 1
J
Parallel
wires
Speaker
terminal
board
Heat sink
Power amplifier board
M
Power IC
Heat sink
N
N
Power amplifier board
Soldered section
c
