Vintage Audio Repair

[nab]

Busy weekend again.

I completed a full re-cap of the Technics I found last weekend with capacitors onhand. Despite looking pristine, there were some with some visible corrosion on the leads, and several more that revealed corrosion after being pulled. Time really is the enemy for these components. Now, combined with the pristine state of the transistors (which degrade mostly due to use, not time), this thing is practically new. Which allowed me to put it in the living room and take a good look at my Sansui G-5000.

And it's a good thing I did. Cause I'm stuck with the glue here too. On the driver board, four of the resistors are visibly corroded by the glue, showing massive corrosion (arrows in picture). To add insult to injury, several of the caps on this board are swollen and likely not working right. I was close to blowing this amp, and the only saving grace is that I really don't listen to things very loud that often, so it never had to deal with massive ammounts of electricity while I've owned it. I really was playing it on borrowed time, but thankfully, I've got the parts onhand to fix it and Sansui was nice enough to make it a removable board to make it easier to work on.

Time to bring this back to a good working order again. Eventually I'll recap the whole thing, but this looks like the worst of it.

The glue, is the dark brown stain near the bottom of the big capacitors in the photo. It goes corrosive over time and was used by most of the main Japanese companies at the end of the 70s through the mid 80's.

 

[nab]

The background is an ad from 1980 that came with the paperwork for the Technics SA-200, just for fun.

I think I'm gonna frame it and hang it up in my work area.

[nab]

Success.

All of the small black capacitors were dead open. They weren't working as capacitors any more. Half of the resistors replaced were also shorted. The large black caps tested marginal.

I was really a loud listening session from blowing this amp. Fixed for now though.

[nab]

Well, this thing is starting to take wings.

Traded the pristine Technics, with a full re-cap I completed a couple of weeks ago (along with 3 turntable repair orders I have out), for this beauty recently acquired by the local record store.

And I'm fucking pumped.

Marantz 2270

You'll all be hearing a lot of talking to myself about this in this thread.

[Buffalo Budd]

[kellerb]

Time to start building and modding guitar pedals as a side-side hustle

[rowjimmy]

Time to start building and modding guitar pedals as a side-side hustle

Do it

[mbw]

Well, this thing is starting to take wings.

Traded the pristine Technics, with a full re-cap I completed a couple of weeks ago (along with 3 turntable repair orders I have out), for this beauty recently acquired by the local record store.

And I'm fucking pumped.

Marantz 2270

You'll all be hearing a lot of talking to myself about this in this thread.

perfect, I'll take it. 

[nab]

Well, this thing is starting to take wings.

Traded the pristine Technics, with a full re-cap I completed a couple of weeks ago (along with 3 turntable repair orders I have out), for this beauty recently acquired by the local record store.

And I'm fucking pumped.

Marantz 2270

You'll all be hearing a lot of talking to myself about this in this thread.

perfect, I'll take it. 

If I don't like it when I'm done restoring it, I will either trade it or sell it, for approx 1.5 - 2k in value. The guy I got it from knows this, so it was all above the board. He's happy to split his risk into separate components, and probably didn't pay that much for it himself. 

But I didn't forget about you and the other Marantz. I was able to haul it out yesterday and do some more troubleshooting and am getting closer to fixing for long term stability. I mean, you could have it right now, it works, but I couldn't guarantee it would work long term. There is a gremlin in there that is causing an extra few volts measurement in key places, and that will wear components out quick.

[nab]

Time to start building and modding guitar pedals as a side-side hustle

Do it

For sure.

And if you understand circuits and repair already, and have the equipment, there's a lot of work here too.

I'm stacked six deep on orders now, and half of those are from word of mouth getting around at the record store.

The other half is me paying for my Marantz 

[nab]

Some rearrangement, some frustrating work this weekend. Added a new rack to hold my projects, which leaves the cinderblock shelves for orders for others. Failed twice on repairing auto return mechanisms on two turntables for the record store. I guess I just understand circuits better than clockwork. Gonna have to do some other work to pay off the Marantz, cause I can't "get good" here fast enough.

[nab]

And in other news, this came into the workshop of one of the people in my vintage electronics facebook groups for repair.

Here or GD thread?

Here

[Hicks]

Some rearrangement, some frustrating work this weekend. Added a new rack to hold my projects, which leaves the cinderblock shelves for orders for others. Failed twice on repairing auto return mechanisms on two turntables for the record store. I guess I just understand circuits better than clockwork. Gonna have to do some other work to pay off the Marantz, cause I can't "get good" here fast enough.

How much you want for that copy of Dookie?

[nab]

Some rearrangement, some frustrating work this weekend. Added a new rack to hold my projects, which leaves the cinderblock shelves for orders for others. Failed twice on repairing auto return mechanisms on two turntables for the record store. I guess I just understand circuits better than clockwork. Gonna have to do some other work to pay off the Marantz, cause I can't "get good" here fast enough.

How much you want for that copy of Dookie?

Not really anything special about that one. It's a repress and they pop up on Green Day's site every now and then. I copped it last summer for like $25 there. It's appreciated to a staggering $27 median price on Discogs now. I'm sure you could find a copy from one of sellers there reasonably.

[rowjimmy]

And in other news, this came into the workshop of one of the people in my vintage electronics facebook groups for repair.

Here or GD thread?

Here

Oh damn.