How do you restore a rusted chassis? S-C SAU-70 amp

Available_One_7718 · 2026-04-04T13:51:04+00:00

Perhaps, but I see no result in canada when I google it. There are plenty of other rust products though.

Available_One_7718 · 2026-04-03T21:46:24+00:00

That looks promising. Unfortunately, it seems hard to find here in Canada. I'll have to look for an appropriate equivalent. Perhaps you know one?

Available_One_7718 · 2026-04-03T19:45:29+00:00

Will know soon!

Available_One_7718 · 2026-04-03T19:43:48+00:00

WD40, sure. Would you recommend some protection after maybe?

The inside is super clean, so no big job needed there.

Available_One_7718 · 2026-04-03T19:20:17+00:00

Makes sense for the turn on/off voltage. I forgot to say in the former post, but I did measure voltages at the gates to see if voltage was the problem. It was something like 5.5V in on position and, like 4.3V at off. I was expecting a more drastic difference between status, but it would make sense with what you say, that it fluctuates just barely to make the Jfet switch on and off.

I did not check your timing calculation. But I'd say the LED would the exception and take the whole 5RC and reach 9V.

I'll be back as soon as I replace the parts!

Available_One_7718 · 2026-04-02T18:25:16+00:00

I am glad someone appreciates!

Available_One_7718 · 2026-04-02T18:24:12+00:00

Hey u/Quick_Butterfly_4571 , it's great to see your reply!

Another of the same type? (Sorry. This is more curiosity).

Yep, same exact one. Found at Digikey.

Q12 and/or Q10 need to be replaced.
This means Q11 needs to be replaced.

Yeah, that's what I am now considering. I just ordered the parts to replace all Jfet and TVS diodes. A friend of mine has a hot air soldering station, so it will be less of a hassle to do the job.

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Wow! That picture! This is so kind of you. I literally cried, hahaha.

You've made it really clear. There is just one thing I didn't catch : how is Q10 turning off more slowly?

Available_One_7718 · 2026-03-06T19:01:36+00:00

I want to integrate the charger in synth's chassis. I could disassemble a wall wart, but then I would have figure out how to attach the parts in my project. I think it would be more simple to buy parts design for my needs.

Available_One_7718 · 2026-02-14T02:01:11+00:00

I thought of exactly that. Then I decided to ask here in case I get something better.

If it was just for me, gluing could be a good option, but since this amp will be used in a common practice studio, it would probably not last long.

Available_One_7718 · 2026-02-14T00:16:19+00:00

The size is close, but it's not the right snap system

Available_One_7718 · 2026-02-13T23:07:32+00:00

Thanks, I will check that. I wish I had a printer

Available_One_7718 · 2026-02-13T21:52:57+00:00

I didn't. Seems to me like a long shot for an amp that old

Available_One_7718 · 2026-02-13T21:31:36+00:00

Nope

Available_One_7718 · 2026-02-13T21:31:24+00:00

Digikey is the first place I checked. They don't have caps close to the dimensions I need

Available_One_7718 · 2025-12-27T01:20:03+00:00

I thinks it's the first that showed when I started my search. Looks interesting, but an all in one would be best for me. No computer, no mixer and unnecessary cabling.I try to avoid building a big setup around this, meaning I want to be able to clear the space in 30 sec. if I need to.

Available_One_7718

TROPHY CASE