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previous: Phil I acquired a Fender Champ amp that ... -- 4/22/2000 10:40 PM

Re: Fender Champ cutting out

4/22/2000 11:04 PM
Ray Ivers	Re: Fender Champ cutting out Phil, The tube may be shorted internally - to be safe, I would replace the 470 ohm resistor with a 470 ohm 2 watt resistor, and the cap with a 25 uF, 50 volt cap (negative side to ground, clearly), and replace the tube too, of course. If you want to fire it up and give the new resistor the 'knuckle test' for heat (low voltages here), it might not be a bad idea. Another thing to check is the voltage at pin 5 (the tube's grid) - a positive voltage here would indicate a leaky coupling cap, and the output tube (valve, sorry) most likely being forced into DC saturation. Bravo for popping the hood, and finding the problem! Ray Ivers R.A.G.E. Electronics

4/22/2000 11:04 PM

Ray Ivers

Re: Fender Champ cutting out

Phil,

The tube may be shorted internally - to be safe, I would replace the 470 ohm resistor with a 470 ohm 2 watt resistor, and the cap with a 25 uF, 50 volt cap (negative side to ground, clearly), and replace the tube too, of course. If you want to fire it up and give the new resistor the 'knuckle test' for heat (low voltages here), it might not be a bad idea. Another thing to check is the voltage at pin 5 (the tube's grid) - a positive voltage here would indicate a leaky coupling cap, and the output tube (valve, sorry) most likely being forced into DC saturation.

Bravo for popping the hood, and finding the problem!

Ray Ivers
R.A.G.E. Electronics

Replies:

Phil Thanks for the advice - and the qui... -- 4/23/2000 12:07 AM