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Wolcott Audio tube amp.what value resistor is this

I have a pair of Wolcott Audio P-220m Tube amp's this morning when I turned them on I got a puff of smoke from one tube socket. I turned it off replaced tube and turned back on.
The amp and tubes light up but it has an Auto Bias and it wont bias letting the amp to play.
I took the bottom cover off and at the tube socket were the tube failed there is a little tan resistor it is connected to one socket pin and solder to a board.
I can see that it is black not like the others so I guess it blew. it looks like a 5 min repair as there is just the two solder points right there

The resistor has orange, white, black and gold stripes on it Can someone tell me the value of it and how to determine the input voltage going into the resistor so I can determine the wattage.

I cant post a pic here of what it looks like but can email that to anyone who can help.

I tried calling Wolcott but they are only open Tuesdays and Saturday from I believe 12 to 3. That doesn't help me right now

This sucks I was finally getting set up for my first Turn Table which will be hear Friday and now this happens.

Thanks for any help you can provide.
Brian
btstrg
11 responses Add your response
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ivanj
35 posts
 
I just had my Wolcotts updated and repaired by Pat McGuire. They sound as good as when I bought them. He says that there is a more reliable configuration of resistors to the output whereas the the late Henry Wolcott's original resistor design (I believe the 39 ohm referred to above) was a somewhat questionable "tour de force" and led to failures. If you have a set of 220Ms and are having problems I suggest you call Pat McGuire. BTW there will be no East Coast repair center.

Take my description of the modification gently since I am not an EE.
reeltrouble1
1 posts
 
I did just get off the phone with Pat McGuire and he is indeed a very good fellow. He can do repair and is on the West Coast in Ca., he said nothing yet firm for east coast service.

RT1
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ivanj
35 posts
 
There maybe an East Coast Service tech set up soon for Wolcott or whatever the company will be. Watch this space.
btstrg OP
185 posts
 
Dannyandelyse

I can't say enough how much I appreciated you help with that number. I got a hold of Pat.

Thank you again!!!!!
dannyandelyse
26 posts
 
Hi B,

Wolcott is in the middle of moving operations and thus hard to grab.Their head tech is Pat McGuire and his cell is 510-828-3561, nice guy and sure to help.
btstrg OP
185 posts
 
Still no luck getting a hold of Wolcott. Any potential buyers need to be aware of this should you ever need service. Also they have no authorized repair service. This isn't good. Replaced the resistor and amp still doesn't bias.

I contacted all there dealers on there web site and they don't know how to get a hold of Wolcott either. They don't answer emails or phone calls.

Just another company with no regards as to what happens for consumer!!
kijanki's avatar
kijanki
4,428 posts
 
1W is even better than 0.5W if you can fit it in.
btstrg OP
185 posts
 
Darkmoebius
Thanks for that web site!! Yes it is a 39 ohms, 5% it is a CARBON FILM resistor as the other said it was. I believe it is 0.5 watt.
I have found 1 watt Carbon Film resistors but am having a hard time finding a 0.5 carbon film ones. Any ideas?
Thanks again that web site is something to keep for future reference!
darkmoebius
900 posts
 
Btstrg, check this resistor value web page to make sure you are reading the value properly.
rodman99999
6,121 posts
 
39 ohms, 5% tolerance Test w/a volt meter set for DC, from the resistor's connection at the board(pos probe) to a ground(neg probe). I suppose you know not to touch anything else in the chassis as there are lethal voltages stored in the power supply caps, even when the amp's turned off. Most amps have bleed resistors to drain that, but- play it safe in there anyway.
kijanki's avatar
kijanki
4,428 posts
 
39 ohm 5%. Pick one of similar size or if there is enough room get one twice larger to be safe. I would avoid inductive wirewound or carbon comp/film resistors just in case. I would still call Wolcott and would replace resistor with original one.
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