Simplistic MosFET HV Shunt Regs

diyAudio Chief Moderator
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No, I wouldn't say uselessly small, its doing some useful filtering still. If you will need more mA CCS for the preamp its another thing. You will be forced to lower the R even more. Even little is good for at least opposing rectification's EMI. In general to be on the safe side, when buying HV rail transformers for future projects use ballpark calculation for expected DC=ACx1.3. If proving some excess you can burn it on R, if proving short due to losses you can't do something.
 
Hi Salas,

a question, below there is my transformer, I use only one of 200V RED ( in Italian Rosso ) to connect to rectification with Black ( Nero)
 

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In the photo my preamp,
as Salas told me, 10mA for one 12AU7 section, two 12AX7 sections, one 6DJ8 section are enough.
I have two SSHV2 but since one delivers 100ma but I thought I would use only one, for the rest I will use Salas SSLV 1.3 Ultra-BIB.
For now, I try with the transformer at my disposal, but I do not rule out buying a better one, for this I asked for advice and where to take it to buy
 

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diyAudio Chief Moderator
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So we guessed about the preamp's mA needs. Remains to see. One SSHV2 delivers "up" to 100mA. You set the limit by CCS setting. Since you are short for spare voltage on the transformer for now, set the SSHV2 CCS conservatively not to lose much voltage on the CRC filter. Much spare current has strong impact on the regulator's sink temperature also. See the SSHV2's pdf manual about details. For heaters power a very good efficient enough solution is also the L-Adapter.
 
diyAudio Chief Moderator
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And SSLV 1.3 is no good?
I thought I would use L-adpater to power a turntable Thorens TD320 MKII has a 16V power supply (see the photo) otherwise do I use L-adapter for heaters and SSLV to power the turntable? What do you think about it ?

SSLV 1.3 is very good. But if too good for just heaters why not use it where it counts more after evaluation. Has a CCS so it will heat two semiconductors M1 M2 (mostly M1 for heaters) when L-Adapter has just one big bipolar pass element to sink.
 
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This type preamps need ca. 15-20mA / channel, so with 25-30mA shunt current the power supply load is ca. 50mA /channel.

One SSHV2 (90-100mA) is also OK for both channels.

Lite Audio suggest 7815 and 7806 (7805 and and one diode from reference pin to ground) stab. for heaters.

http://www.lite8.com/product.php?action=723

p.s. Using shunt stabilisers for indirect heater is a luxury category, totally unnecessary.
 

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