Vintage Harmon-Kardon (800+) Troubleshooting Questions

[Bishop]

Hi all,

Moving out of my folks' place, I managed to uncover an old Harmon-Kardon 800+, which is now sitting in my living room. I fired it up yesterday - for the first time in at least five years - and ran into some issues.

One, I'm only getting sound out of the right speaker (but oh, what a sound!)
Two, I get a lot of scratchiness and noise when I turn the volume pot, but, again, only out of the right speaker.

I have it hooked up to play component audio from my television, and from the H-K it goes to two vintage Advent loudspeakers, both of which work when hooked up to my old shelf system. I noticed that the "rear left" speaker fuse is blown, but I feel like this wouldn't make a difference since I have the speaker hooked up to the front left channel.

Any tips on how to get this thing back up and running would be appreciated - if this is something I should be paying a professional to do, that's an option, but I'd rather save the money and do it myself. Bad connection with the speakers? Just generally dirty and grimy? Are the fuses wired in such a way that one blown fuse would cause problems with all the channels? And so on and so forth.

Thanks!

 

[Bishop]

Well, I'm going to take a crack at replacing ALL the fuses and crimping the wires more securely. Let's see what happens.

 

[Bishop]

Well, that worked and got things up and running, but I'm now having a weird problem where the volume seems to self-adjust. Sometimes it's preposterously loud at 25%, other times it's whisper-quiet at 90%.

Any thoughts?

 

[slipperybidness]

Clean the volume pot with a product designed for such tasks, like Deoxit

 

[Bishop]

Cool - it's also worth mentioning, I think, that the wiring in my house is complete garbage. For example, even when plugged into a power conditioner, my guitar amps get very bad hum unless everything else in the house is turned off.
But you folks think that Deoxit in the volume pot will solve the volume adjustment issues? To rephrase the problem, the volume fluctuates and occasionally begins to clip, even at very low settings.

Is there a way to clean the volume pot without disassembling the unit? I'm looking at some photos online of what this thing looks like inside, and it looks absolutely terrifying.

Thanks so much for the help, everyone!