The simplistic Salas low voltage shunt regulator

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Its normal you have hotter BJT if its CCS is the strongest. If you think it will hold, then OK. Just keep an eye on it until it persuades for reliability.

The 0.15V difference is mainly due to Vref and Vbe. Idss and heat can slightly change it (Vbe), but not a good method. If you can find another 6mA 2SK, is better for reducing heat on the BC.
You can try your lack with changing some Zener or BC, but I would not touch it, because I think that 0.33% tolerance on 45V nominal is already way good.
 
fine ,just for learning max safety T on Bc ? now is 26.5° but this summer 35°....but I have a lot of stuff to diy a better heatsink
just a personal thinks that to92 is 10° up pw mosfet ;)


too late for play vinyl ,I will report today after retest the idss on 55° because the other is not too hot,and If I understan well no problem if there is imbalance on idss beetwin +/-

thanks ,this shunt is strong :D
 
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There is a practically steady gm curve for BC550/560 from 5mA to about 10mA current. So the gain of the regulation loop is the same. Because you have 40V across them with the IDSS CCS as load in your 45 Vout case, you understand that using over 6mA brings no gain, just heat. 2SK170BL are strong, just make nice mini sinks for the BJTs. I don't think that thy are going to fail. We are just being rightly conservative. OK even if the odd BC fails in some months, no big deal. You just change a Euro 0.05 part. Its not an $50K commercial amp so for your dealer to lose face.:D
 
I change the 7.28/30 with found 7 and 7.1

R6 mod sound very better, smooth and spatial

:cheers: thanks a lot!!!!!!


The end ! new summer project MiniA:devilr:


Salas just to learn ,if burn the 0,05€, bc I lost a rail in driver? and I have strong offset that burn my 340€ fullrange? or this can happen only if I lost one rail in pw stage??

I will never buy a amp , at last parasound jc1 :angel:
 
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Nice to know you listen well with the shunts on an EB amp driver stage. Franky went to Hollywood in the end!:D

As for what happens with your amp if you lose one driver rail, you must ask EB, I don't know the amp.

What I know is that if you lose a BC550/560 in the shunt, you lose regulation, not the rail. Its shunt, not series.;)

P.S. Now we need big close up photo of your double mono symmetric V1 reg with all LEDs alight, and no oscillation certificate with your signature, for Ikoflexer not to lose any more sleep over phase margins.:clown:
 
:D :D
 

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iko

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Joined 2008
Salas said:
Nice to know you listen well with the shunts on an EB amp driver stage. Franky went to Hollywood in the end!:D

As for what happens with your amp if you lose one driver rail, you must ask EB, I don't know the amp.

What I know is that if you lose a BC550/560 in the shunt, you lose regulation, not the rail. Its shunt, not series.;)

P.S. Now we need big close up photo of your double mono symmetric V1 reg with all LEDs alight, and no oscillation certificate with your signature, for Ikoflexer not to lose any more sleep over phase margins.:clown:

:D Why, I like SCI-FI

But yes, at the end of the day I will settle for "Simplistic Salas Reality" TM ;)
 
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