Simplistic mosFET HV Shunt Regs

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#1,843
merlin el mago said:
How can do or better how can calculate?
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merlin el mago said:
I have connected pre-pre MC to TT gnd, it's necessary to connect pre-pre MC gnd to Puresound P10 MM?
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You can calculate the real current for each stage by the drop on its load resistor using Ohm's law. That circuit is an MM stage, needs a pre-pre for MC. Normally the TT GND goes to pre-pre only.
 
#1,844
B+ 260V for ECC88:

Left
39K 62V = 1.58mA & schematic 4mA, how can calculate how much more resistance needs to get 4mA?
Right
39K 61V = 1.56mA & schematic 4mA, how can calculate how much more resistance needs to get 4mA?

B+ 206V instead 220V both channels
68K 37V = 5.44A
How can calculate to increase B+ till 220V?
 
#1,845
Its a matter of bias by the cathode resistors. Besides having less or more than noted the circuit is biasing OK given there are tubes tolerances, you should have had sound. Ask those in the dedicate thread here is OT, here its for the regs.
 
#1,848
Had a the ground wire pull of the board. Ran it a while before I realized it wasn't regulating as Vout = Vin-30V with no adjustment via trimpot.

Found o voults on the middle (collector) of MJE350, replaced it and now voltage adjusts fine. So if someone has a similiar issue with running with a bad ground and no regulation afterward try replacing the MJE350 first.
 
#1,849
Curiosity

G'day as Salas,

As pm'd, the schematic for the pre I want to use +/- 200V for.

Thanks,
 

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#1,850
There is a voltage doubler there. You should find around 320-330VDC with a 120VAC secondary before the first CRC filter. There are also 2x100V Zeners for stabilizing at 200VDC in the second CRC filter. If you want to use SSHV, delete the Zeners and adjust the single 10K R element to drop no less than down to 220VDC at the 2nd CRC output so to feed the reg. The drop on R will be the CCS current times R. By measuring the drop on first CRC filter as it is now (Vacross 10K//10K) you can find the current draw need of your circuit. Divide that drop by 5K and set the CCS in the SSHV for load current+20mA and for 200VDC regulated output of course.
 
#1,851
Ok, that makes sense I reckon, to be painful, which setup in regards to schematic should I use, also, I remember that you recommended a +50v to voltage out on the voltage in? In the last 140+ pages, is there a list of parts you recommend? I know some guys were using bc506c in stead of b etc. Least that's what memory is pulling up.
Thanks Salas,
 
#1,852
With the JFET SSHV I slacked it down to 10-20V. Depends on where you can easier burn the heat, on CRC R elements? On heatsinks for CCS Mosfet? Needing big pre filtering?. With 22uF caps you rather need high R in CRC. Keep in mind that the 9610/610 (you need +/-V regs for that schematic) will burn (Vin-Vout)*CCS current. The 840s will burn 200V*(CCScurrent-LoadCurrent). R in CRCs will dissipate RVdrop*ICCS. Check that the ratings will take it. Use that setup but delete the Zeners: http://www.diyaudio.com/forums/powe...tic-mosfet-hv-shunt-regs-182.html#post2604016
I recommend polypropylene C2,C3 capacitors, and Teflon bypass 0.022uF. There are no BC transistors in the Jfet SSHV, those were in the first round of regs. R1 adjusts CCS by (Vleds-VgsQ1)/R1. Good luck.
 
#1,856
Salas regulator and Curcio Daniel II

Hi Salas and Jean-Charles!
First I has a 20 years old Sonic Frontiers SFL-1 in my storage, and this is actually a Daniel II, and SF get the permission from Joe Curcio manufactured under the name Sonic Frontiers during 90s.

I want to improve the piece, first I don't understand, since the stock unit the Curcio circuit has come with its own HV regulator. How you put the Salas HV shunt regulator with the stock regulator?

Can you give me more details how you accommodate the tentlabs shunt regulator into the Daniel II circuit?

Tentlabs has offered E-choke for a while, can I mod the Daniel II with the following arrangement in the power supply?

Power transformer --> Schottky diode --> Tentlabs E-choke --> Salas regulator

I saw couple different Salas regulator, which one should I go for this project?

SSHV for Phono and Tube Pre Kit - Quanghao.com

Shunt Regulators - Quanghao.com

Thanks!
 
#1,857
Our experience here is limited to what feedback is given by members on mostly DIY circuits and self built Shunt PSU marriages. About brand name preamps modding and various kit PSUs or boards we can't guess results or make recommendations or judge pricing. The Tentlabs shunt module is low voltage anyway, isn't it? If not experienced with High Voltage better don't do it yourself, its dangerous and potentially lethal. Ask for the help of professional modding services. Who's Jean Charles by the way?
 
#1,858
#1,859
Forgot about it. So its tested and reported very positively on your preamp by Jean-Charles here about a year ago. Go for it then. PM or email Jean-Charles for any details if he is not watching, also. The stock regulator looks like LM317 Maida style from the schematics near the post you linked. The high voltage one is the one called SSHV or simplistic HV, whatever with HV.
 
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