Simplistic MosFET HV Shunt Regs

[Salas]

Is there any problem using positive regulator for negative supply, just wire it the opposite?

A positive SSHV will burn out. See its mirror in the above your question link. Its not that different.

 

[Joshua_G]

A positive SSHV will burn out. See its mirror in the above your question link. Its not that different.

Sorry, I don't get it. A positive reg output has plus and minus, or common. When it is fed from a floating supply, what difference does it make if I will wire the positive out of the regulator to the ground and the negative out to the client?

 

[Salas]

Now you mention floating supply. I haven't done it though.

 

[regal]

A tip for the LEDs to use on the PCB's , Digikey P11506CT-ND LED ORANGE S-GW TYPE SMD they give right at 1.8V, fit the board nicely too, no worries about them becoming antennas.

Has anyone tried capacitor rolling of the 1uf zobel output cap. With my SSHV WE417A Spud Headamp this is really the only cap in the AC path.

Think it would be worth trying a K75 in leu of the cheapest 1uF metalpoly cap I could find on Digikey?

 

[Salas]

The 1uF in the voltage reference is the most influential subjectively. Really good combos are Russian oils shunted by russian Teflons. You can sub both 1uF caps on the reg with your chosen best. Its audible.

 

[regal]

The 1uF in the voltage reference is the most influential subjectively. Really good combos are Russian oils shunted by russian Teflons. You can sub both 1uF caps on the reg with your chosen best. Its audible.

I try out a few and report. I have a pair of 1uf russian oils and .1uf russian teflons.


thanks

 

[merlin el mago]

heatsink for IRF9610

This heatsink will be enough for IRF9610?

531202B02500G Aavid Thermalloy Heatsinks

 

[Salas]

Nobody can answer if you will not state how many Volt and what mA that Mosfet will be handling with your setting.

 

[merlin el mago]

How can do to measure the Volts & the mA?

 

[Salas]

DVM Vin-Vout, DVM across VR1/R1 value.

 

[merlin el mago]

DVM Vin-Vout, DVM across VR1/R1 value.

Vin 293V
Vout 260V
R1 = 56R

Wich load value in ohms to adjust the Vout to measure the current trought R1?

 

[massimo]

Merlin, this link might be useful Resistencia eléctrica - Wikipedia, la enciclopedia libre
(end of page)

La Ley de Ohm also

 

[merlin el mago]

If insulation pad on Mosfet's back fails by heat one time in the future, having the box as a sink its either spectacular HV short to ground when with a grounded box, or DC electrocution hazard for anybody touching the box if ground is not present or faulty. This is high voltage. Don't take it lightly. A 22K 10W will be good for dummy in your case.

Catched the info about dummy load

 

[merlin el mago]

I have on hand one Caddock MP925 15K with heatsink will be enough as dummy load?

 

[Salas]

Vin 293V
Vout 260V
R1 = 56R

Wich load value in ohms to adjust the Vout to measure the current trought R1?

You need to see voltage across R1 too. VR1/56=CCSmA.

 

[Salas]

I have on hand one Caddock MP925 15K with heatsink will be enough as dummy load?

That will work for eating 17.3mA at 260V. Enough to ''massage'' the reg.

 

[merlin el mago]

Thanks I will measure & let you know.

 

[merlin el mago]

Bad news the power tx of Pure Sound P10 only gives 188-189VAC so only can get 217VDC regulated & I need 260VDC

 

[kacernator]

Bad news the power tx of Pure Sound P10 only gives 188-189VAC so only can get 217VDC regulated & I need 260VDC

If your power transformer has enough current you could use voltage doubler before regulator - you then half the current capability of the transformer.

 

[merlin el mago]

If your power transformer has enough current you could use voltage doubler before regulator - you then half the current capability of the transformer.

I mind not because is to power B+ for ECC83 & ECC88 tubes.