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Technics SA 500 Receiver

I have an Technics SA 500 receiver that I bought new when I was in college (long time ago). The receiver worked great and I loved it as it was the first piece of audio equipment I purchased. As time went on I purchased other receivers and the SA 500 ended up getting past around to different family members (dumb move in hindsight) until it circled back to me recently.

I tried to fire it up the other day and it would not power up. I looked at the fuses and they appear in tack. The unit is in decent shape, not perfect, but not beat up. It's got about 35 years of dust on the inside which is not helping matters.

I would love to get this running again and use it in my basement just for fun. I'll never sell it even if it doesn't work but it would sure be great to see it in operation again. I'm a total novice when it comes to electronics but I would appreciate any thoughts or advice as to how I might go about restoring it.

Thanks



Re: Technics SA 500 Receiver

When I turn my SA-500 receiver on it lights up but other lights such as the fm stereo and power lights do not come on. Also, the signal and tuning needles are not activated. I already changed the two fuses and still have no reception. What shall I do? Thanks for any response.

Re: Technics SA 500 Receiver

Being 40 years old - this receiver will require a thorough restoration if its to be used and expected to be reliable.
And not a half-baked quick fix, either.
Age takes its toll on things.

Re: Technics SA 500 Receiver

Thanks for the perspective.

Re: Technics SA 500 Receiver

There is a small circuit board with three fuses on it; the fuse for the power transformer may be open (note: I have seen many fuses that look good but are open). The power switch may be bad (open all the time). The power transformer has an internal thermal cutout; it's function is to open if the transformer gets too hot. These sometimes fail and the transformer doesn't work; if the transformer has pins coming out it may be possible to bypass this thermal cutout. You should get a tech to do this if you are not electronics savvy.

Re: Technics SA 500 Receiver

Thanks, I appreciate the insights and advice.

Re: Technics SA 500 Receiver

Unit worth repair and should be simple to isolate falt. Do you have a good vom and know ac from dc?

Re: Technics SA 500 Receiver

Thanks

nabeelsayegh's picture

Re: Technics SA 500 Receiver

Agreed...these units do not have a very complex circuitry on them. First I would isolate if this is a power supply issue or something more down stream. There is no relay protection circuit on these, just the speaker fuses in the back and I am pretty sure you already checked them. I have restored many of these; particularly the SA-200's and 300's. One thing I have noted is that 'sometimes', it may appear dead, but all the lamps are blown giving the illusion of death. Any way, I would start with tracing voltage out the transformer into the PS. Full Wave rectifiers could have blown, could have bad caps. If it is really dust contaminated, then first blow it out with compressed air (outside) before you do anything. Dust is actually conductive and it can cause all sorts of issues.

Ultimately, if you are serious about restoring this guy, you are looking at needing to recap it...which basically means replacing all of the electrolytic capacitors. At this age, most if not all no longer have their original values. In some cases, these could even open or short out; either situation could prevent a system from working correctly.

Re: Technics SA 500 Receiver

Thanks