cascode referance voltage = rail voltage/(R25+R27)xR27
so for 50V rails it will be:
50/(10K+4.75K)x4.75K= 16.1V
for 32Vrails:
32/(10K+4.75K)x4.75K= 10.3V
Audiosan,
Proved these work in real work measurements.
Thank you.
Biasing seems a little trickier than standard F5.
I am going to do some more testing of values for R5,R6. I think I will go to 2.2K from 1K.
I find as the voltage climbs, my pots have limited and timid offset adjustability. I removed the thermistors to see if it helps, and it does not. Makes it easier to set bias for me.
Attached Pic 1 -Cascoded version running 48V, Jfets at ~16v
PIC a version 2 one running strait out.
Attachments
good to hear
what is your bias goal? and how many outputs?
Well, for testing 1,2,3 and 4 I am trying to build several variations to cover functionality of the board and part behavior.
But does this affect Bias? Both version 2 and 3 schematic show same R values here for R5,R6 - P1,2.
Tea Bag are selling any power supply boards?
wrong thread for my boards - but not currently. I am considering.
I would recommend the one from chip amps.com under the Aleph PS section. If you look around you can get some decent size bug caps on it, plenty of space for 5 .47R resistors and a place for 2.2K 5W bleeder resistors. And six big caps, 4 TO-220 type diodes can go here, and each can have a 2" tall heatsink. I will try to post a pic of one, if nobody has one quickly. It's <10.00usd. That's hard to beat!
here is 3 without the diode's one with 6x10.000uF 80V
2 with 6x12.000uF 35V
they all have 2.2Kohm bleeders and 4.7uF bypass caps. CRC resistors is 4x0.47ohm on one. and 5x1ohm on the 2 others.
2 with 6x12.000uF 35V
they all have 2.2Kohm bleeders and 4.7uF bypass caps. CRC resistors is 4x0.47ohm on one. and 5x1ohm on the 2 others.
Attachments
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Has anybody seen a currently available PS board for dual secondary transformer? Or even just a board for the rectifiers (TO 220) There have been some around, but I don't see any available right now. Sure would be nice to see something with thick traces and hefty plated holes. Heat sinking 4 devices/rail is a PITA
how about the ones they sell here in the forum store P-PSU-1V20 - PSU Cap Diode Board - Boards
how about the ones they sell here in the forum store P-PSU-1V20 - PSU Cap Diode Board - Boards
No diode heatsinks?
.No diode heatsinks?
This is the issue.
For those of us who think our discrete devices have some impact on overall sound.
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