JH100 plate voltage

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M2061x
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JH100 plate voltage

Post by M2061x » Wed Mar 21, 2018 3:19 pm

Hi,

The plate voltages in my JH100 are about 530V or even more. Depends how you bias it.
How could I lower the plate voltage to 500?
What would be the best way to do this?

Thanks.

shakti
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Re: JH100 plate voltage

Post by shakti » Thu Mar 22, 2018 8:03 am

What is your wall voltage? Make sure you have the voltage selector on the amp set to the highest value (240V if you're in Europe, 130(?) if you're in the US.

If your wall voltage is lower than the amp's voltage selector, you will lower all voltages in the amp accordingly. That said, 530V seems to be a typical value for these amps.
JTM45 RS OT, 1973 18W, JTM45/100, JTM50, JMP50 1986, JMP100 "West Coast", AC15, AC30, BF Super Reverb, Boogie Mk 1, Hiwatt CP103, DR103

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wdelaney72
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Re: JH100 plate voltage

Post by wdelaney72 » Tue Mar 27, 2018 11:50 am

I 'd agree this seems accurate for voltage.
My JTM 45/100 is somewhere around there... a little less, but close.

Biggest thing is to have NOS tubes or something that is known to be able to handle that kind of voltage. I have Shuguang KT66 from TubeTramp...very durable. Not sure if they're still available these days. I know the quality / durability of the Shuguang EL34 went down and Terry said "to hell with ya!"
Walter

"There's no great thing in being a soloist. I think the hardest thing is to play together with a lot of people, and do it right." - Angus Young, 1984

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