This came in because the owner said one of the input jack sockets has fallen inside the unit, and one channel not working as expected, so wanted that fixed and a general service.
The plastic retaining screw was missing/broken and led to the connector being unsecured:
Noticed a non-original pot fitted too, and a couple of other issues, one being the Depth knob was hanging on by a thread (wonky, impact damage). The remains of the shaft came off with the knob!
Had a spare replacement of the correct era so fitted that
Then found the Distortion pot with switch was fractured, a replacement was not available so was disassembled and did best to glue back together (will be fine in normal use)
The vibrato speed pot was non-original, was wired loosely and of an incorrect value (should be 100K log according to the service info for that revision) – the fitted pot was too ‘fast’ and was more a warble/flutter than vibrato:
This was also replaced with the proper PCB mount version, and the earlier found pot was replaced with the correct diameter shaft (the one in there had been taped up to try to hold on to the knob! – last photo before replacement):
Found CH1 was disabled by a small shorting wire on ch. output, which took a while to spot! Lifted it off and was then working – not sure why this was done.
Also found the Bright switch was solder-bridge shorted to be always on, the switch had very tarnished contacts so perhaps was being a bit noisy and instead of fixing, the previous person just disabled it!
Then saw the reverb tank housing was missing the proper screw and rubber bushing, and had been ‘secured’ with gaffer tape, used a couple of rubber grommets to provide support at both ends – a bit of a hack but was effective – unfortunately the proper screw would no longer fit so re-used the old one as it was a tight fit.
Insides a lot better now!
The chorus and bit bucket delay output was checked and adjusted as appropriate per service data.
Knobs wanted a good clean so went in for the ultrasonic treatment (photo prior)…
Brass nuts fitted to the front jack connectors and freshly cleaned knobs refitted, all tested ok, nice sounding unit, very powerful!
The cabinet base castors were missing but apparently were needed to be off to fit in the vehicle the customer uses for transportation, so didn’t fit new ones – pity as it’s a heavy beast!