Simplistic MosFET HV Shunt Regs

All well then. What type is it? SSHV1? Post some picture with your (SRPP?) phono.

Yes it is SSHV1.I will try to get some decent pictures in the morning if you are still interested after seeing that mess but this is a work in progress so no nice enclosure here and since I like to use only 20-30cm armtube wire to phono input there are space limitations(the sound is on the oposite side ,beautiful).
The phono is Eric Barbour 6s17k-v circuit.I only changed output tube with 6n6p-i led biased so no electrolyte in chain from PSU to phono.RIAA uses Soviet teflon caps that are opened from their metal enclosure and unwounded on desired value and the windings are then wrapped with cotton thread from outside to desired value (if you need 39,6 nF unwind the cap on around 39 nF and with wraping you ad the rest of 0,6 nF).
This way the cap sound much better because the windings of original cap are pretty loose inside.
After few years of using SSHV1 I finally found time to replace sand diodes with hybrid vacuum rectifier.I started with 6x4 then ez80 and ez81.The sound was wonderful in mid frequencies but else was missing somehow and after thinking of the problem I tried ey88 which is 220mA damper diode and the whole spectrum is here including mids but not so euphonic like with EZ types.I suppose that magic is distortion of 90 mA tube (60mA consumed by SSHV) which work near it's current limits.
The tubes in supply are completely quiet (black sound stage) and almost no hum compared to sand diodes on max volume.
Maybe this is of topic but just wanted to encourage someone who wonders himself about result regarding tubed PSU.It is worth the effort ,especially in the phono circuit.My researches resulted that weak rectifiers leads to romantic presentation and tough are more like solid state regarding dynamics but still pleasant ,in fact the best of both.If you have heavy heat-sink you can fine adjust the type of the sound from romantic to more honest by loading the tube rectifier more or less with regulator CCS settings ,one among great features of Salas regulator.With EZ types you are stacked with romance only if you need higher regulator ratings.
Can somebody suggest other rectifier tubes and describe it's sound with various loading but only indirectly heated ,since I don't have 5V windings.I also use py83 which sound more on flat side when is lightly loaded but it's extremely detailed.That is the nice side of the tubes ,they are mud flexible ,the different sound for each day:wiz:
 
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Changinf 840 as we speak. Got new tube and went to retest and kids had switched probes and i didnt notice. Nice pop and now replacing entire sensing circuit.

KIDS around open HV rig ???? :hot: LOCK them out.

Upper bjt measuring 9mV lower bjt 1.6V. Irf840 is 3.5V. I fi place probe to measure Vgs of irf 840, output voltagr begins to rise. Seems upper bjt may b eproblem.

That upper one is responsible to bias the fet also, it can be the problem.
 
As far as i can figure, the problem ha sto be with the voltage refernce for the bjt 's. They are not controlling the shun tproperly and it is shorting all the current away. When i measure Vgs, i steal some current from the gate, lowering the Vgs and along with it, the curren tthe fet will pass. This reduces shunt current and the rails begin to climb. The bjt's begin to balance better. I dont full yunderstand the control mechanism though. Is it the jfet.? The led is working fine or at least test good.
 
Don't you ever sleep? Realized with one o fmy pics, I still have a problem with B+ on front tube. No blue glow. This is the channel with broken trace. I think i have another one somewhere that i have to find. The rectifier tube is Winged C 5u4g black plate. HEHEHEHE. Cans are 40uF. Since i am going to be putting all this in seperate case, i may get more capacitance as it only cost $6 a can. Side note, most simulations i have done show two smaller chokes being more capable than one large in prefilter. Any advice or warnings on this. Do two chokes create more noise or possiblity for ringing.
 

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No sleep till Brooklyn. He, he. 5U4G accepts 40uF on CLC max. CLCLC is even better. What do you mean by no blue glow? That one is about electrons hitting glass impurities, there i some in a few tubes, no in others, depends on making process quality, but no consequences in tube life. You can measure steady regulated DC on both plate resistors, same drop on plates, yes?

See how they used to make them BTW:
Mullard Valves - The Blackburn Story - Part 2 - Parts Of A Valve - YouTube
Mullard Valves - The Blackburn Story - Part 3 - How A Valve is Manufactured - YouTube
Mullard Valves - The Blackburn Story - Part 4 - How A Valve is Manufactured - YouTube
Mullard Valves - The Blackburn Story - Part 5 - How A Valve is Manufactured - YouTube
Mullard Valves - The Blackburn Story - Part 6 - How A Valve is Manufactured - YouTube
 
No sleep till Brooklyn. He, he. 5U4G accepts 40uF on CLC max. CLCLC is even better. What do you mean by no blue glow? That one is about electrons hitting glass impurities, there i some in a few tubes, no in others, depends on making process quality, but no consequences in tube life. You can measure steady regulated DC on both plate resistors, same drop on plates, yes?

See how they used to make them BTW:
Mullard Valves - The Blackburn Story - Part 2 - Parts Of A Valve - YouTube
Mullard Valves - The Blackburn Story - Part 3 - How A Valve is Manufactured - YouTube
Mullard Valves - The Blackburn Story - Part 4 - How A Valve is Manufactured - YouTube
Mullard Valves - The Blackburn Story - Part 5 - How A Valve is Manufactured - YouTube
Mullard Valves - The Blackburn Story - Part 6 - How A Valve is Manufactured - YouTube

You talking 40uF for first C in CLC or total? NO blue gloe with these is an idiciation of B+. Was glowing blue last night when my son and I sat in the dark and looked at the pretty lights.