Yamaha CR-840 Advice

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Hello. Sorry if this is the wrong forum for this.

I have an old Yamaha CR-840 receiver that is pretty dusty on the inside but powers up and has audio out of both A and B channels. It's scratchy/cuts in and out on certain/most dials (loudness, volume mainly but others too.) I have read that you can service the dials internally. Inside the case I see some of them have little metal cylinders with spinning ends that turn to change setting. If I were to dust these out, where exactly should I aim the cleaner (de-oxidizer? I read that radioshack sells specific cleaner)? I don' want to get the cleaner on anything I shouldn't. I read the term "pots" and assume the little cylinders are the pots but I don't want to go squirting cleaner without asking the professionals.

Also, I read that a receiver that goes bad can damage the speakers attached to it. I just found a pair of Klipsch Heresy speakers at Goodwill for cheap and don't wanna blow them up : )

Is it even worth trying to clean/tune up this amp or should I just look for another one. This amp has been in the family and I know it was never "abused" but it's also been in storage and just plain sitting for a long time. I read that the capacitors/transistors/resistors could be replaces for not too much but I'm only vaguely familiar with soldering ( I understand how but my fine tuning isn't that great). There just appears to be a lot oft his things in there, some are kinda leaning over a bit but honestly I don't know what I'm looking for as far as looking for failing components outside of the obvious blown fuse or burn marks. Any advice would be appreciated. I like the vintage sound/look of the amp. The thing weighs a ton and I just doubt anything I could afford would really rival the build quality or sound. Thanks again for you time.


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A CR-840 is not a bad little receiver, and it does feature protection circuitry. Looks like you should hit this one with the canned air though - outside. (Compressors may spit out a bit too much oil, but if you know one that has pretty clean output, it could also be used.) More extreme measures may be needed if the unit used to belong to a smoker, but you better know what you're doing when giving it a good wash...

Restoring vintage audio equipment is not rocket science per se, but there is a fair amount of knowledge involved, and it really helps if you are able to tell a pot from a pan to begin with (learning curve number 2). I recommend not trying to reinvent the wheel, you're certainly not the first one to do something like this - go to places like AudioKarma and read up on what others have done and what's advisable.

Should you find you're a total klutz when it comes to things electronic (which happens), find someone who isn't.
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