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previous: MJ Harnish Here's the story: I've been fooli... -- 7/25/1999 5:58 PM

Re: Low B+ voltage: Is it the xfrmr?

7/25/1999 8:47 PM
R.G.	Re: Low B+ voltage: Is it the xfrmr? From your description, it sounds like a voltage doubler circuit. There are some voltage doubler things like that. If you 're getting a reasonable 6.3VAC across the filaments under operation, then I'd bet on a doubler circuit. The extra diode ties the first lead to ground when the line reverses, and the red lead to ground pulls the (-) of the cap (and amplifier ground) down, effectively doubling the voltage. Try it.

7/25/1999 8:47 PM

R.G.

Re: Low B+ voltage: Is it the xfrmr?

From your description, it sounds like a voltage doubler circuit. There are some voltage doubler things like that.

If you 're getting a reasonable 6.3VAC across the filaments under operation, then I'd bet on a doubler circuit. The extra diode ties the first lead to ground when the line reverses, and the red lead to ground pulls the (-) of the cap (and amplifier ground) down, effectively doubling the voltage. Try it.

Replies:

Farrow I'm with R.G. on this one. Guild a... -- 7/26/1999 11:55 AM
MJ Harnish You've got it RG. Bruce @ Mission ... -- 7/26/1999 1:42 PM