new idea of DHT heater supply

[ThorstenL]

Konnichiwa,

...and what's the max current the chokes can swallow

No idea, they are listed at 400VA/230V. They are for mains filtering.

...and the ripple you get?

The ripple, I forgot, but it was a few dozend mV peak-peak, right in line with Duncan Amps PSUD predictions, something like 10mV or so RMS, 100Hz with a very nice round waveform.

Sayonara

 

[martinab2]

The circuit using mercury rectifiers posted earlier in this thread got me thinking..
What about Tungar bulb rectifiers ? Designed for low voltage high current applications. Has anyone tried this out for heater supplies ?

 

[grimberg]

The common mode choke

Kuei,

I am working on a project using 2A3s and would like to build a PSU similar to the one you presented here. I read your postings in this thread and also on Audio Asylum but could not find the specs for the common mode choke before the 300B heaters. Could you tell me more about it?

 

[ThorstenL]

Re: The common mode choke

Konnichiwa,

I am working on a project using 2A3s and would like to build a PSU similar to the one you presented here. I read your postings in this thread and also on Audio Asylum but could not find the specs for the common mode choke before the 300B heaters. Could you tell me more about it?

It is an absolutely generic 5A common Mode choke, quite large size/core. I originally got a load of them when work threw out around 100pcs of Compaq PC's years ago. I actually salvaged parts from all of them (on company time, I was required to destroy the Harddrives for some stupid reason), especially Chokes, MKP Cap's, some of the PSU cap's from all the PSU Boards I pulled and loads of rubber HDD mounting gromets. Great find. I'm still using up the stocks

Sayonara

 

[grimberg]

Kuei,

Are you saying regular PC PSUs have them? I have a few old ones lying around; I think it is time to take them apart.
What inductance should I expect to measure?

 

[ThorstenL]

Konnichiwa,

Are you saying regular PC PSUs have them?

Yes, but often the quality is crappy. Have a look. It sits right next to the Power Input and the higher the power of the PSU the better. The old PC's I salvaged where from high spec 286 PC's with 250W PSU's, even better sat in 500VA Server ones....

Sayonara