Ripped up my old 5 channel 807/6cb6 based amplifier because I need to rebuild into a new rack mountable chassis. Decided to go with a completely new design.
Still havent ordered any parts yet. PSU design was inspired by Peter Millett's DCPP.
This will still be 5 channels just like the old one. About 40 mA per GU-50, probably around 8 mA per 6CB6 to match old amp. Of course ill be playing with bias as i made it adjustable
Just wanted some potential commentary before i ordered the psu parts.
Ill be using different mosfets and of course better choice/fewer zeners to get the required voltage. i ran with the stock parts in the program
Still havent ordered any parts yet. PSU design was inspired by Peter Millett's DCPP.
This will still be 5 channels just like the old one. About 40 mA per GU-50, probably around 8 mA per 6CB6 to match old amp. Of course ill be playing with bias as i made it adjustable
Just wanted some potential commentary before i ordered the psu parts.
Ill be using different mosfets and of course better choice/fewer zeners to get the required voltage. i ran with the stock parts in the program
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Hmm, worth a try. But i have doubts that -48v is enough to keep the anode current down. might need to order another/series two 48v supplies together.
Im guessing 300v would be sought after to obtain a flatter curve?
just realized i typo'd out the intended plate current for gu-50's (40 mA)
Im guessing 300v would be sought after to obtain a flatter curve?
just realized i typo'd out the intended plate current for gu-50's (40 mA)
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heres the fully assembled and tested psu board:
12.6v DC and 400v AC input,
500v 300v,150v DC output, no current limit or constraints. full regulation even at open circuit.
6.3v 3A output for operating the small signal pentodes
5x -0v-72v bias pots
5x -0v-5v bias pots
bias supply powered by this guy:
http://www.murata-ps.com/data/power/ncl/kdc_nmt.pdf
12.6v DC and 400v AC input,
500v 300v,150v DC output, no current limit or constraints. full regulation even at open circuit.
6.3v 3A output for operating the small signal pentodes
5x -0v-72v bias pots
5x -0v-5v bias pots
bias supply powered by this guy:
http://www.murata-ps.com/data/power/ncl/kdc_nmt.pdf
I am just about done with the chassis wiring. all the major components are in place but its taking a bit of time to carefully solder to the tabs on the plug i chose for inputs/outputs. Slow progress as i have been distracted and busy with work lately and have been working on it in sessions. also need to resolve a issue i had with a resistor.
Amp is completed, but i need a new mosfet for main b+ ripple filter. the one i have there failed due to a failed zener diode
otherwise works exactly as intended. the fixed bias on the preamp works wonderfully.
i went with 500v and 6au6a's in the preamp positions
otherwise works exactly as intended. the fixed bias on the preamp works wonderfully.
i went with 500v and 6au6a's in the preamp positions
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for anyone that cares. this reflects current state of the design:
sorry for a little bit of messiness in diagram showing lowish voltage design
the lm338 is only running one of the 6AU6A's, the other 4 are running in pairs of two off the 12.6v supply. a bit more power efficient that way anyways.
sorry for a little bit of messiness in diagram showing lowish voltage design
the lm338 is only running one of the 6AU6A's, the other 4 are running in pairs of two off the 12.6v supply. a bit more power efficient that way anyways.
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