Fig. 15
1. Disconnect the wiring to thë right channel circuit board and fold it back onto the transformer. Loosen the
clamp holding the electrolytic capacitor next to the output terminals, and lift Á capacitor out of the way.
2, Disconnect Á leads to the output sockets, place the clamp board over the output connectors and re-solder.
It is advisable to tin the output connector tags before positioning Á clamp board. This makes soldering easier.
Replace the capacitor and reconnect the tags to thé right channel amplifier board.
CLAMP CIRCUIT ALTERNATIVES
T1 - 2N4992 or BS08A-03
T2 - Sc141B or TIC226B or RCA T2800
1. Disconnect the wiring to thë right channel circuit board and fold it back onto the transformer. Loosen the
clamp holding the electrolytic capacitor next to the output terminals, and lift Á capacitor out of the way.
2, Disconnect Á leads to the output sockets, place the clamp board over the output connectors and re-solder.
It is advisable to tin the output connector tags before positioning Á clamp board. This makes soldering easier.
Replace the capacitor and reconnect the tags to thé right channel amplifier board.
CLAMP CIRCUIT ALTERNATIVES
T1 - 2N4992 or BS08A-03
T2 - Sc141B or TIC226B or RCA T2800
Fig. 15
VOLTAGE SELECTOR
SOLDER BOARD & WIRES
TO OUTPUT SOCKETS
OUTPUT SOCKETS
INPUT SOCKET
9
CLAMP CIRCUIT
Introduced co-incident with amplifier PCB M12368 iss. 9 ¤ serial number 9001. All 405s with serial numbers 9000
¶ under being returned for service, should be fitted with å clamp board as shown below.
At serial number 59001 Á clamp circuit was fitted as an integral part of the amplifier board M12565 iss. 3.
Û function of this circuit is to monitor t˙ê d.c. component of the output. In the event of å component failure
which causes excessive d.c. voltage, thé circuit will short circuit the amplifer output ¶ thus protect the speakers.
REPLACING THE CLAMP BOARD
If it is necessary to replace å clamp board the following instructions should be followed:
To Next Page
Loading...