I bought some junk (Kenwood 1100u)

One thing that is sort of cheaper now are the output tubes. For the longest time you had to buy old american tubes which of course were expensive. Now with the new Tesla you have close to this for alot less clams and matched nos tubes. Believe me it could be alot worse.
 
I know. Me and another person was searching the net last night and found a couple of matched pairs around 60 for sylvania NOS. Ouch.

Are the JJ's any better than the sylvania, westinghouse, or fishers?

If im gonna do it, I want to do it right.
 
she is up and running now.

I spent saturday replacing the coupling capacitors and some other bigger caps in the amp section. She needs filter caps bad as there is somewhat of a hum in the background (goes away when touched by hand). But that after the holidays. Looking at the JJ/tesla 100X100uf caps for it. Possible the new JJ tubes as well.

Before and after pics.

I cleaned the controls with deoxit and fixed the tuner to were its close to scale, but its still way off. The tuner sting looks stiff, dry and stretched so that will have to get fixed by somebody else.

At least the tubes dont overheat now. I got a 30 sec video of it running, but no site to host it.
 
the hum is because of some lack of grounding somewhere, is it a three prong cord? you should probalby put one in and connect the earth to the chassis somewhere to get rif of that
 
She's looking good. Great job!!! :thmbsp:


For the dial string, I believe you can obtain modern nylon ones from AES or similar supplier. Did you manage to get a service manual for the unit? If so, there's usually a dial stringing diagram in it.
 
I wouldn't worry too much about the dial now. The main thing is to make the receiver as reliable as possible and that recap certainly helped in this regard.

Is the hum too loud? there's always going to be some hum present in old tube gear. This is in sharp contrast to 1970s solid-state gear that featured high capacity, low voltage electrolytics. Back then, large capacitance was expensive, and the units used the minimum required for good performance.

Like Rockmonton suggested, it's also a good idea to check for a possible ground loop. Is the hum still present with all sources disconnected? If so, there's a grounding issue inside the receiver or the filter capacitance needs to be increased.
 
ground loop is most definatley what it is if you touch it and it goes away! i'm like a ground loop nazi..... CHECK IT
 
Thanks for posting the video. She's looking mighty good, playing some tunes.

I downloaded the file in less than 10 secs with my broadband connection :banana:
 
I did some more recapping to it. Replaced some caps to ground and changed out the caps on the low filter switch. Ever since I changed the low filter switch caps, the "pop" in the right channel has dissappeared. Also the switch itself doesnt pop when turned on and off.

The slight hum I was having is gone too. every cap I have taken out tested bad, so I went ahead and ordered all the small caps in the preamp section. Almost 40 in all. The loudness switch is giving me problems with channel balance when turned on, so that will be the first thing I recap.

Everytime I replace more caps, the better she sounds.
 
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Looks like your on the right track.
Best to just do a total recap. Also check the resistors in any of
the areas your having trouble with just to make sure the value
is within tolerance.

Good Luck.
 
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