Advice Needed - Kenwood KR 8050

[roger2]

I mean can you describe the damage. At the bottom of the pic, do I see stubs of wires sticking out, or no? Higher up in the pic, is that a hole clear through the board? Does it look like this damage was caused by heat or something else?

 

[DubbleA_ron]

There is a hole in the board. Apparently someone tried to bypass that part of the board by bringing wiring up from the damaged area of the board to the two resistors at the top right of the board. When I used a multimeter to verify that the power was being routed around and away from the damaged area, as soon as I touched the resistors where the wires had been connected they arched and popped (nice big fireball).

I am done with this project. I'll either have it professionally repaired or wait for a unit to come up for sale.

I appreciate all of the advice everyone has provided. At least I've learned a few things.

 

[roger2]

This would be a tough repair even for a very experienced technician. I think that letting it go for now is a wise decision.

If you have developed an interest in Vintage gear, there are lots of paths you could go down where the reward-to-misery ratio is a lot more favorable, lol. Don't throw away that 8050 though. It could still have value to the right person or in the right situation. And it was among the higher end of Kenwood's product line in its time.

Good luck...

 

[DubbleA_ron]

This particular model seems to be difficult to find online. I really like the 8050 but I suppose I could look for similar models (the 6050 model seems to be fairly similar with less features). I'll find something. Just wish that this story had a happy ending.

 

[roger2]

On ebay search for Kenwood KR-8050. Then, on the results page scroll down and look on the left side for a check box that says "sold listings". Currently there are 4 or 5 recent sales of this model. So they are floating around out there. But yeah, lots of other options too, in Kenwood as well as many other brands. In receivers, if you want the FM capability and the extra lights, along with the extra complexity that goes along with those things. Or in integrated amps if you don't really need the radio part. Kenwood KA-7100, KA-3500, KA-8100, KA-5500, KA-6100....etc, are all worthy machines, and much simpler than receivers. There are also larger integrated amps than those I listed.

Your 8050 story is not concluded, it is just on pause for an indefinite time period. It will have a happy ending...

 

[Moondust]

I have an 8050, and started a thread other day about taking one apart...How did you get yours apart? Did you remove the side panels in order to remove the top?

Obviously that is the only way to do it, please dont call me a big dummy...

 

[DubbleA_ron]

Correct. You'll need to remove the side panels first and then remove the top panel. After that it's pretty it's pretty easy to see what you'll need to unscrew in order to remove things. Shouldn't be too difficult. Just take it slowly and make sure you have a magnet or something you can put your screws in so they don't get lost. I also recommend taking pictures if you aren't sure you'll remember which screws go where.

Good luck!

 

[Moondust]

According to the pics its possible that it had been repaired previously - but I do not see anything, that did a "freaking idiot". Some resistors have been changed, ya.

Here are some pics of a KR-8050 I have had. I still have another unit. Sorry for the poor quality of these pictures.

The original posters pictures shows 2 fuses...In your pics I see 3 fuses, why is that?

I took my 8050 apart yesterday to clean it. I already put it back together, but did take some pics prior to cleaning it though. I will post them later...

But mine only has 2 fuses as well, not three. Also, one of my fuses had the white ceramic coating (?), and other one had a thin wire inside of it. Which is different than both of yours...

I will post a few pics later. I forgot to take pics after I cleaned guts, but it really wasn't too dirty to begin with though. Little dust and light lint. I sprayed switches as well with crc contact cleaner followed by crc lube...

 

[jeffe]

I've seen worse PCB burns by passed and units brought back to life. After a little surgery, it may be good to go. As an heirloom, and a really nice piece of gear, it deserves a chance. I'd invest a couple hundred for parts/labor if that much, (BUT shipping sucks...) to repair that issue. It may bring it back to life with nothing else required. I know my local tech could do it. He took care of a big burn thru on a Yamaha CR-2020 for me.