Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Bieworm on September 05, 2022, 08:32:46 am
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Hey guys
Is it all right to put the standby switch on the HT center tap when using a half wave SS rectifier and fixed bias amp (6V6GT)
It's the intention to add a bias vary trem on the 6V6's...
thanks
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Standby, is really a controverse matter
However to place it on the CT isn't the best choice, a tech can have problems during manutention
better a mute switch
Here you can read something about
http://www.valvewizard.co.uk/standby.html (http://www.valvewizard.co.uk/standby.html)
Franco
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Is it all right to put the standby switch on the HT center tap ...
Yes, but depending on how a bias supply is derived, the voltage on the bias caps may rise.
when using a half wave SS rectifier and fixed bias amp (6V6GT)
It's the intention to add a bias vary trem on the 6V6's
It's unusual to use half wave rectification for HT supplies. With a centre tapped HT winding, you can splash out on an extra diode for a push pull (2 phase), full wave rectification (https://www.valvewizard.co.uk/fullwave1.jpg)
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You have a half wave SS rectifier with a HT center tap? I've never seen one. Bet you really mean a ss conventional full wave rectifier.
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You have a half wave SS rectifier with a HT center tap? I've never seen one. Bet you really mean a ss conventional full wave rectifier.
Yes I meant the full wave conventional.. sorry😬
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The wide Panel tweeds ('5Dthis' and the '5Dthat') had standby switches on the CT of the High Tension winding and then Fender stopped this practice.
But then 'Fender' put it back on the Eric Tremolux. So ...
I've used it with 5U4 rectifiers and had no problems. YMMV
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I finished the schematic. Might be some tweaking involved at the bias, but this should work.. I think.
BTW, I put the standby switch after the rectifier...
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The paraphase seems wrong. The 270K gridleak on the non-inverting path should be grounded? Seems like positive FB at that 4 wire node connected as shown.
(https://el34world.com/Forum/index.php?action=dlattach;topic=29320.0;attach=100503;image)
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The paraphase seems wrong. The 270K gridleak on the non-inverting path should be grounded? Seems like positive FB at that 4 wire node connected as shown.
(https://el34world.com/Forum/index.php?action=dlattach;topic=29320.0;attach=100503;image)
I guess it's kind of confusing, but it's a LTP PI. Look at the green marking balloons.. they connect to the power tubes...
I borrowed that part of the schematic from Sluckey's Deluxe Reverb Lite
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The paraphase seems wrong. The 270K gridleak on the non-inverting path should be grounded? Seems like positive FB at that 4 wire node connected as shown.
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I think it’s a version of floating paraphase, ie that node is a virtual earth http://www.valvewizard.co.uk/paraphase.html
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The 6G3 Brown Deluxe Also has this type of PI. I thought this was a LTP PI... well, learning things here... :smiley:
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The 6G3 Brown Deluxe Also has this type of PI. I thought this was a LTP PI... well, learning things here... :smiley:
Yes, you’re using an LTP.
We’re discussing the 5D4 phase splitter, sorry I meant to make that clear :icon_biggrin:
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The paraphase seems wrong. The 270K gridleak on the non-inverting path should be grounded? Seems like positive FB at that 4 wire node connected as shown.
…
I think it’s a version of floating paraphase, ie that node is a virtual earth http://www.valvewizard.co.uk/paraphase.html
It is a floating paraphase. It is self balancing. See figure 12.31 in the attached.