Looking for a PCB / kit for a bipolar tube rectified PSU

[luvdunhill]

Hi everyone! I originally posted here

http://www.diyaudio.com/forums/showthread.php?s=&postid=1274416#post1274416

looking for some power supply recommendations. Since, I've decided that I would like to try a tube rectified PSU. Please see the above link and the links contained within for details on the project. I would really like to use a PCB for the project if at all possible. Any recommendations? I'm looking for something rather simple that would output +- 400 VDC.

 

[Tweeker]

Getting the +/- 400V with tube rectification is going to involve multiple isolated filament windings. It wont be rather simple. Theres a reason you dont see many tube rectified amps with bipolar supplies.

 

[luvdunhill]

... hm, what about two 400 V DC supplies hooked together? I've seen a few "kits" on Ebay that claim they can put out 400 V DC ... I've done this before in the solid state PSU world, but I have no idea how stupid this might be in the tube world

 

[Tweeker]

+400 and +800 could be done more readily, though is much more dangerous than +/- 400.

I dont have any negative versions handy, but heres an illustration of a bridge rectifier done in tubes to show why Im a bit dubious of any simple project. 2 of the diodes cannot be a duodiode.

 

[luvdunhill]

tweeker, I guess I just don't see why it should be so hard. ;( I'm a bit slow though. I thought that differential amps used dual supplys?

hm... any other ideas out there?

 

[Tweeker]

Er, what exactly are your psu requirements?

A differential amp does not require a negative rail, though it may be helpful. It normally does not require bipolar. No need for more than ~200 volts across the tail, and thats in the worst case of a pentode CCS.

 

[luvdunhill]

here's a link:

http://headwize.com/projects/showfile.php?file=gilmore4_prj.htm

basically, +- 400 VDC, < 150 mA

Thanks again for the help!

 

[luvdunhill]

I think I may understand the confusion now Tweeker... Assume that you have two 350 VAC inputs, from a 350-0-350 transformer.

 

[Geek]

Hi,

I would really like to use a PCB for the project if at all possible. Any recommendations?

I have a PCB that can do hybrid or SS of what you need (though not bipolar all-tube).

Would it help?

Cheers!

 

[luvdunhill]

Re: Re: Looking for a PCB / kit for a bipolar tube rectified PSU

Hi,



I have a PCB that can do hybrid or SS of what you need (though not bipolar all-tube).

Would it help?

Cheers!

maybe this would work, although again I'm not sure. You allow for using a full wave rectification. In my case, would using two diode tubes allow for more current that paralleling the 2 sections of a full-wave rectifier as a diode? I guess this is part of my confusion. If the full wave rectification would work, then yes two of your boards would work quite nicely!

 

[luvdunhill]

hm, just came across something called a hybrid Graetz bridge rectifier... seems like just what the doctor ordered. Some say there isn't a sonic difference between the hybrid and fully rectified... any comments?