Amp repair question - PeachParts Mercedes-Benz Forum

123c · #1 07-13-2008, 07:53 AM

I picked up an old Sansui DC Servo intergrated amp yeterday at thrift store for $5, I plugged it in to see if it powered up, and it did. When I got home I found that the right channel didn't work, however when turning it on, it would briefly power up for a second or two. I noticed that it requires a 4 amp fuse, it had a 2 amp fuse in it, I had a 3 amp fuse that I stuck in it. If I put a 4 amp fuse in it, would that fix it so that both channels will work? Or does it sound like something is fried on it. I went through with contact cleaner and cleaned everything, and I checked all the connections, and everything is good. One last thing to note is that it makes a buzzing and statiky noise for about 30 seconds after starting it up, and the lights will flicker, does that sound like a bad power switch?

BTW, there was a Carver preamp sitting next to this for $10, I should go back for it on Monday if it is still there.

Kuan · #2 07-13-2008, 08:29 AM

Sounds like you may have a leaky capacitor somewhere. That, or bad solder joint somewhere.

123c · #3 07-13-2008, 08:38 AM

The capaciters do look like they are leaking a little...

G-Benz · #4 07-13-2008, 08:50 AM

Find a vintage audio repair shop and have it fixed properly!

I bought a Pioneer intergrated amp for $10 on eBay, and although it powered up, the transistors were fried! Cost me $180 to get the unit refurbished. Still worth it, but consider that those really great "deals" are deals for a reason...

mpolli · #5 07-13-2008, 03:19 PM

Putting in a bigger fuse won't help. Unless you have skill in electronics you will have to find someone to fix it. The amps I have worked on all had blown output stages (transistors or modules). But it could technically be anything. I wouldn't think a "leaky" cap would cause total failure of the channel. Does a leaky cap look different than a normal one? I have never seen a cap actually leak anything except ones that exploded...

123c · #6 07-13-2008, 06:10 PM

I think I will just shelf the unit for a while, and maybe part it out down the road if I don't get it fixed. I will examine the Carver Preamp, if it is still there tomorrow, maybe a Carver Amp will show up on the shelf as well.

Maybe I will run across something good when I go to Seattle next weekend, at one of the thrift stores. The Seattle Goodwill used to have good stuff, but they started to put everything on eBay. The Ballard Goodwill, I've seen a few good things, but have passed. My mom is always finding high-end items there, that need a little TLC (elbow grease) to be perfect.

123c · #7 07-13-2008, 08:24 PM

I was checking some connections, and I somehow did something, and now the thing lights up, but no output from either channel. I am thinking its toast now. I mostly bought the thing to be my iPod player.

Gurkha · #8 07-13-2008, 09:29 PM

www.audiokarma.org

You won't find a better place for advice and resources for getting your unit fixed.

123c · #9 07-14-2008, 06:24 PM

The Carver preamp was gone, but there were some old AR speakers, and some old Advent speakers, which look like they showed up today...

p. rex · #10 07-15-2008, 02:54 PM

Just out of curiosity, what model number is it? I'm something of a vintage audio buff myself; I'm running a Sansui AU-999 amp and TU-999 tuner, circa 1971.

Just so you know, by the way, these old things are money pits. You can't get out of the repair shop with less than a $100 bill, and full electronic restoration (new electrolytics, set DC offset, clean everything) will cost you $200 or $300. Maybe worth it for a classic heavy-ass '70s piece, but I suspect yours is from the early or mid '80s, and those aren't worth as much.

123c · #11 07-15-2008, 09:58 PM

It's from the early to mid 1980s, it's not worth that much at all, but it was cheap, and it was worth the $5 if it worked. I am sure I can sell it for $5 as a parts unit. I used to have a Sansui G-6000, but that is gone, and I had an old Harman Kardon 630, that I gave to a friend.
I am hoping to pick up something this weekend when I am in Seattle.

123c · #12 07-17-2008, 09:18 PM

No finds yet in Seattle, but my mom did score an old Singer sewing machine for $20, that didn't work, but I got it going with some Lube...

123c · #13 07-19-2008, 07:22 PM

I just scored some older Bose computer speakers for cheap, I will use them for my iPod player for now.