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Duncan, seems you're busy with V3, but perhaps you have time to quickly check an inconsistent response when using a valve based voltage doubler.? I have a setup with 330V 21R secondary supplying a 2x 5U4G per arm rectifier into? 47uF 1R filter caps with simple 7.5kohm load.? It provides about 780V output across 7k5, but the concern is the markedly different diode current waveform asymmetry, and the resultant different voltages across the series connected output caps.

I tried different options settings (accuracy, frequency, leakage) but no change.? There is some variation with different valve diode models, but the asymmetry doesn't show with ss diodes.? I'm using Windows build 76, V2.22.

I can't quickly find this topic issue discussed on-line.? My previous use of doublers in PSUD2 have been ss based, but I have a valve based doubler in an amp on the bench now :-)

Ciao, Tim Robbins

Hi Tim,

Thanks for letting me know. I'll try and duplicate your circuit this evening and see if I can find any clues as to what's happening. More news later...

Regards,
Duncan

Hi Tim,

I've duplicated your circuit using the values listed in your message, and I can confirm that something is badly broken. Looking a I(T1) the positive and negative excursions should be the same but are anything but.

Will have to take a deep dive on this and start prodding in the software to find out what's going on. Probably won't get a chance to review/resolve until Sunday.

Regards,
Duncan

Duncan, thanks for taking a look.? No rush from my perspective - just wanted to confirm there was an inconsistency - it's an esoteric situation, which is likely why this may be the first awareness of it.? Ciao, Tim?

I noticed it seems to be related to the valve diode model, as HV valve diodes (eg. 575A and 3B28) show symmetric behavior.?

OK that's a good bit of info, thanks.

It does make me concerned though, as the model is the same for all the diodes; solid state as well as vacuum tube. At least I can duplicate the issue at this end, and to be honest, that's half the battle with fixing things :)

Regards,
Duncan