Hoffman Amplifiers Tube Amplifier Forum
Other Stuff => Other Topics => Topic started by: kagliostro on June 01, 2017, 05:05:35 am
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For those who can have interest on the B-15N Ampeg a link that I've find and that contains a lot of good info
https://www.talkbass.com/wiki/technical-amplifier/ (https://www.talkbass.com/wiki/technical-amplifier/)
Franco
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nice find! I see you don't sleep well either :laugh:
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Ciao
May be it was not so early in the morning, here we are near Greenwich meridian :wink:
add 7 hours to the time you see on the forum :smiley:
Franco
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For those who can have interest on the B-15N Ampeg a link that I've find and that contains a lot of good info
https://www.talkbass.com/wiki/technical-amplifier/ (https://www.talkbass.com/wiki/technical-amplifier/)
Franco
cool! thanks for sharing that K!
building another all octal-socket amp is in the forecast. i'd probably go with SS recto.
--pete
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Question on fixed bias in that documentation. How does the biasing circuit work to provide a negative voltage to the grids?
Is it because you have both + and neg coming out of the secondary taps?
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Unless I'm looking at the wrong schematic, it's not fixed bias, it's cathode biased no?
~Phil
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https://www.talkbass.com/wiki/technical-amplifier/#24-converting-a-b-15n-from-cathode-bias-to-fixed-bias (https://www.talkbass.com/wiki/technical-amplifier/#24-converting-a-b-15n-from-cathode-bias-to-fixed-bias)
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The early ones were cathode biased. Later ones were fixed bias. Keep scrolling down the page and you will see.
It's just a very simple half wave rectifier. Nothing special. Hundreds of amps use that same circuit.
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Oh thanks mantisman and sluckey, that makes more sense :) Yup that's a bias circuit I've seen over and over in my limited experience too.
~Phil