Sunday, February 2, 2020

Ratshack Receivers, Contact Cleaner, and the Fine Art of Indolence

Welcome back. It's tax time! I'd normally ditch doing my taxes on my day off by building a new module (I have PCBs now to finish the Reverselandfill's "Noise" Lunetta circuit mods, but I am waiting for parts to arrive.....).

I also have a gig in about 3 weeks I need to get ready for, as well as an album I said I'd have done and delivered year end.

But instead of working on any of that, I wasted a wonderful amount time this weekend repairing some old receivers and other audio crap I found on the sidewalk near where I live.

DIY?  Not entirely, but there are lessons to learn from this. Read on!!

The Onkyo Receiver and Technics turntable both worked flawlessly and required almost no cosmetic work. The Onkyo was sitting outside a neighbors house w a sign "Free"; the turntable was a castoff from a DJ I did a recording project with--he said I could have it if I could fix it, and even when I told him "N.P.F." he still told me to keep it.

But is it communism?
 I see discarded goodies left on the street in my neighborhood all the time: clothes, shoes, toys, record albums, and every now and then, of interest to one's DIY audio jones: discarded electronics. Not sure it's like that where you live? Perhaps you have relatives or friends who have old stereo dookie they want to get rid of; if you can get your hands on old gear, and need to procrastinate big time, you can try your hand at bench repair/getting them back up to working condition, or gut 'em for parts.

I recommend taking a break from whatever you do over and over and try this....it beats the hell out of death and taxes.

No "before" pictures for any of these...but this Lafayette LA324 was filthy beyond belief, and to my surprise cleaned up very well after disassembling. After a top to bottom scrubbing, some solder joint touch up, pot and switch cleansing, and a few wire replacements, it works as if brand new. Nevertheless, I almost gutted it for the knobs and pots (which are nice for an otherwise cheap stereo) but I dunno, when I was a youngster I loved reading the Lafayette catalog, so I had to keep it around.

To date, I have found three receivers on the street, was given a dead Technics turntable that in reality worked perfectly, and was gifted a really nice pair of Klipsch bookshelf speakers.



To my surprise, every one of these antiques was so easy to fix that it didn't end up in the junk box, landfill, or cannibalized for parts.

Another fully disgusting  bug infested receiver--complete with spider webs and insects living inside--was this Realistic STA65 a neighbor left on the side of the road. After a few hours cleaning: good as new. The knobs are great, and have a cool 70's vibe, but the receiver worked so well after reassembly I ended up giving it to the husband of the lady who gave me the Klipsch speakers below; he is a self-proclaimed Radioshack/Realistic audio fetishist and was thrilled to add this to his island of misfit toys.

The wife of radioshack guy got a pair of nice Klipsch speakers in her divorce settlement from her first husband back in the 80s.  #1 ex hubby apparently loved these speakers more than his penis. She hates this ex so much she never wanted to see him, or these speakers, again, so she gave the Klipsch's to me. After cleaning the wire posts, which were a bit corroded: they work perfectly and sound really good. Not sure her ex was as easily put right, right?



What you get when something can't be repaired: Slide pcb mount switches from an old discarded US made security system. They appear to be of very high quality. I used a Hakko FR300 to de-solder them.
The star of the show is contact cleaner. Turns out Deox-it is somewhat legendary with electronics repair folks; after trying it, this stuff really works!! By following the directions on the label, it seemed to me even the most filthy pot or switch could be brought back from the dead. I had to disassemble a lot of the gear before applying generous shots of contact cleaner, but once this was done, the pot exercised, the process repeated, and the component left to dry overnight, everything started working again.

Another star is my FR300 Hakko Rework tool.  It was expensive but if you are salvaging hardware from junked gear, a good desoldering station is an excellent investment--it will pay for itself eventually by allowing easy extraction of PCB hardware from junked boards.






So what does any of this have to do with synthesizers you ask? A slight connection. I bought this Euro STGS Sea Devil filter used, and it had a scratchy Frequency pot.  Normally I would have thought it was a leaky cap or cold solder joint or some other damn thing, and would have gone crazy trying to fix it at the PCB level, but after having brought back a few receivers that had similarly scratchy tone controls I figured why not hit it with contact cleaner. That did it--it was just a dirty pot-- Fixed!

OK enough, now on to taxes.  A tech colleague of mine has a saying: "Indolence pays".  Maybe, or maybe not, but killing time on the bench cleaning up discarded audio foolishness can be way fun. My parting advice: waste time and don't breathe the fumes!

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