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Hoffman Amps Forum image Author Topic: Hot Rod deluxe problem  (Read 2154 times)

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Offline LooseChange

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Hot Rod deluxe problem
« on: January 08, 2012, 07:56:43 pm »
I've got a HRD on the bench and I have a strange problem I can't seem to figure out.
There is voltage on the grid of V1A, Pin 2. About 0.8volts with the tube in and around 2.1volts with the tube pulled. Got any ideas?

http://www.el34world.com/charts/Schematics/files/fender/hotrod_deluxe.pdf

Thanks!
Call me Dan
www.fydamps.com

Offline Tiny_Daddy

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Re: Hot Rod deluxe problem
« Reply #1 on: January 08, 2012, 09:38:15 pm »
Leaking over from Pin 1? Lift the 100K resistor and see if it goes away.

Offline LooseChange

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Re: Hot Rod deluxe problem
« Reply #2 on: January 09, 2012, 06:42:35 am »
I'll try that.

I've worked on dozens of these amps and this is a first.
Always a fun time with these amps, pc board and all.

Thanks!
Call me Dan
www.fydamps.com

Offline birt

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Re: Hot Rod deluxe problem
« Reply #3 on: January 09, 2012, 10:43:24 am »
i would check the ground connection of that first gain stage.

 


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