Technics SU-7700 Right Channel Issues

[Hydrogelic]

Its hard to know how to put this , but does anyone know what might be causing the problems with my amp ?

The right channel simply either doesnt work , or works so horribly that its not worth hooking up . Origionally this could be fixed by jimmying the TAPE MON switch on the amp (Probably the problem here , because everything is hardwired) , but now only the left channel seems to work efectively .

Ive opened it up , and had a peek inside ; replaced the fuses and shoveled out the dust (in an electronics safe manner) but i still cant see the root of the problem , which im guessing is a dry soldering in the TAPE MON switch .

Any ideas , suggestions , schematics , manuals , links or hints would be much appreciated .

[bikehorn]

corrosion in the tape monitor switch. you need contact cleaner/lubricant like Deoxit. while you're at it, spray out all your switches and pots.

i own an SA-300 receiver of the same era and it has similar switches and pots. i had to spray the Loudness switch to get it working, and the pots were scratchy until i sprayed them. otherwise, it sounds great. how do you like yours?

[Hydrogelic]

Originally posted by bikehorn
corrosion in the tape monitor switch. you need contact cleaner/lubricant like Deoxit. while you're at it, spray out all your switches and pots.

The switches are enclosed and mounted such that the Mode , Rec tape , And Tape Mon switches are inside the same , hard to get at , component block . Not wanting to be difficult , but Considering the eventuality that i cant get the lubricant in there , then can you suggest any other alternatives ?

[bikehorn]

Originally posted by Hydrogelic


The switches are enclosed and mounted such that the Mode , Rec tape , And Tape Mon switches are inside the same , hard to get at , component block . Not wanting to be difficult , but Considering the eventuality that i cant get the lubricant in there , then can you suggest any other alternatives ?

sure you can't get in there? it was a bit dicey for me, i had to remove the lighting bar for the tuner on my receiver and used the long thin "straw" that came with my can of contact cleaner to get it right in there. still, not impossible. i don't know how your amp is laid out but i'm sure it can't be THAT hard to get in there. the switches are long, thin rectangular thingies on the PCB, right? there's a little hole on top, into which i sprayed the lubricant. seems to have worked.