[Peter Fabian]

Thanks. I’ve ascertained the same in the meantime. The wire was being rotated, but there was so much resistance that it just popped out from the groove it would sit in.

 

Once I figured that it’s the idler that should be moving, I was able, with some considerable force, able to make it jump up in its track. There was a decent amount of old, hardened grease. After a bit of cleaning with IPA and some WD40 lubricant to get it moving, it now jumps along fairly happily. Just need to fit the belt (on the way from you as we speak) and it should be good for a while.

[Peter Fabian]

I have a similar issue since recapping my unit. Before recapping, I did not have right channel (in either of speaker 1, 2 or headphones) but otherwise it worked fine.

Now, when I recapped it, I did, at first, blow one of the power supply filter caps (I misread the markings and connected negative to ground on both sides, oops) so there’s a chance I blew something downstream then… it doesn’t seem like the power side gets any voltage? But the control side does.

 

So what is happening now is – when I turn on the machine, it goes into standby. When I touch a program button, it does come out of standby, but no program lamp goes on. (The volume and tone/balance control lamps do all come on). I’ve replaced the blown cap with another one correctly.

The machine is not reacting to Standby switch, unless held. If held, the relay keeps switching off and on. The program lamps work fine when voltage is sent through them when disconnected from the amp.

 

Can I test these transistors in situ without desoldering them? And if needed, how do I check the IC9, other than visual damage?

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