Receiver Not Making Sound: Realistic STA-820

[cmnparlance]

The short version: I have a Realistic STA-820 that powers on but makes no sound. Anyone have any basic troubleshooting ideas?

Some more details and background:

I bought it used earlier this year and everything seemed fine, but after some time I noticed that one channel was quieter than the other. I had a local guy look at it and he was able to get it working great by (I think) simply cleaning out the tape monitor button.

Everything was fine for a month or two, until all of a sudden one day the thing stopped making sound. The lights come on, everything looks right visually, but no audio. I've tried all the functions and settings, with speakers and with headphones, to no avail. Unfortunately, the guy who did the work on it has since moved out of town. I was able to reach him via text and he suggested working all the buttons and dials to see if that made a difference, but so far that hasn't helped.

Does anybody have any basic troubleshooting tips for this kind of problem? I could of course clean everything out with DeOxit, but I already did that a few months ago, before having the guy look at it--and I'm pretty sure he did it as well when he worked on it. But if that may make a difference, I would certainly do it again. I can open it up and see if anything looks out of place (if someone tells me what to look for) but unfortunately my knowledge of electronics is pretty limited. I did check the main fuse in the back and that looked OK. A schematic of the receiver can be found at hifiengine, on the last page of the manual (but it doesn't mean much to me!).

My next move may be to find someone else to repair it, but these guys are getting harder and harder to find and are often quite expensive, so I thought I'd see if there are any easy things I can try first.

Thanks for any ideas.i

 

[century tek]

I guess the easiest thing to do would be to wiggle/push the tape monitor a couple of times. Aside from that, you might need to go deeper inside.

I am not familiar with this unit. Did it used to make a click sound a few seconds after you turned it on?

 

[cmnparlance]

Thanks for the reply. I did work the tape monitor button a bunch of times, but no dice. I could try actually cleaning it, but those buttons are hard to access, and I'm hesitant to start unscrewing things and removing panels since I don't really know what I'm doing.

I don't remember a sound I'd describe as a click, but it did (and still does) make a bit of a "pop" in the speakers when turned on--not loud enough to be alarming, so I never paid it much mind. Seems like the kind of thing that could be minimized by just keeping the volume turned down or disengaging the speaker selector button. Like I said, it still does make that sound when the power button is pushed.

 

[century tek]

A relay inside would sound like a distinctive click or snap from under the chassis. Even if the speakers were turned off, if it had a relay, you would still hear it click.

I looked at the schematic at hifi engine and it has no speaker protection relay.

Aside from vigorously moving the buttons and switches to see if it is a dirty problem, it might have some internal fuses inside but since you say you don't know what you are doing, I'll juts leave it at that.