Hybrid rectification tube/diode

[gmant123]

Hi All and happy new year!!!

I want a make a 300b power amp, with hybrid rectification, tube/diode, but on hand only have HER508 diodes, they can work??
The tube rectifier is a 5Z3.

Diode Datasheet

Example of rectification..


Thanks for help..

Alberto.

[Ketje]

You didn't indicate the sec.voltage of the transformer ??
The max reverse voltage of the diodes hase to exeed (largely) the Vp of the transfo.
Ater the rec.tube the capacitor is limited to 32µF not 100 !
Mona

[gmant123]

Hi, thank you for reply.

Is a choke load PSU, transformer secundary 510V.
Trafo-hybrid rectification-10H choque-45uf film-5H-45uf film, one 5H per channel.

Regards.

Alberto.

[merlin el mago]

It seems HER508 diodes are OK.

[ginetto61]

Originally Posted by gmant123

Hi All and happy new year!!!
I want a make a 300b power amp, with hybrid rectification, tube/diode, but on hand only have HER508 diodes, they can work?? ....
Alberto.

Hi !
i am curious to understand if these diodes could work fine in a power supply for a dac.
Do you have any advice or direct experience ? have you used them in your project ? what the outcome ?
I have decided to use them instead of more high-end options ...
maybe wrongly.
I am worried about their possible switching noise mainly.
I have bought 100 on ebay.com to try them out.
Thanks a lot.
Kind regards, gino

[nigelwright7557]

I have used same series of diodes in a couple of valve amps and there is no switching noise.

[ginetto61]

Originally Posted by nigelwright7557

I have used same series of diodes in a couple of valve amps and there is no switching noise

Hi ! thanks a lot for the very helpful advice.
I am playing with some low voltage regulator kits built around the lt1083cp.
being cheap some parts quality is suspicious
So I am replacing mostly caps and diodes.
For caps I use mainly Nichicon and Panasonic.
For diodes I need some axial ones.
(for now I am going to leave any other thing unchanged).
Then I found this thread and I am happy to have got an important confirmation.
I read al lot about diodes switching noise.
From what I understand it results in spikes at high Hz, a kind of noise very difficult to suppress with normal regulators (they have very bad PSRR at Hz > 10kHz usually = ineffective).
I still wonder if it would be better a slow switching type ?
But I have bought some of these and I will try them out soon.
Thanks a lot again.
Gino