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August 02, 2026, 07:56:42 pm
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Hoffman Amps Forum image Author Topic: First amp build  (Read 10911 times)

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Offline sluckey

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Re: First amp build
« Reply #50 on: August 02, 2026, 05:51:52 pm »
Grid-41VDC
That's way too much bias voltage. Should be about -15v for EL84s.

Offline Mongrel714

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Re: First amp build
« Reply #51 on: August 02, 2026, 06:16:29 pm »
Grid-41VDC
That's way too much bias voltage. Should be about -15v for EL84s.

How do I go about fixing that?, Ive noticed Ive left off some ground wires, Im fixing that, then I will re check.
Thanks for the comment !!

Offline Adrien

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Re: First amp build
« Reply #52 on: August 02, 2026, 07:16:57 pm »
Is that +41 or -41V? Looks like your bias diode is backwards. Fix that and double check before you put the tubes in again! The bias voltage should be negative relative to ground. 

Offline Mongrel714

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Re: First amp build
« Reply #53 on: August 02, 2026, 07:40:39 pm »
Is that +41 or -41V? Looks like your bias diode is backwards. Fix that and double check before you put the tubes in again! The bias voltage should be negative relative to ground.
Ah ok, thank you, will do!

Offline Mongrel714

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Re: First amp build
« Reply #54 on: August 02, 2026, 07:45:25 pm »
The bias resistors are backwards!

 


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