Circlotron power supply question

[woody]

Tube Lovers Anomymous uses a single 330 v supply to derive
the 2 floating 165 v supplys. Is there any thing wrong in doing this. And how would you even begin to calculate the ripple voltage?

[Dave Cigna]

You can't derive two floating supplies from a single supply (well, maybe with additional transformers...) But never mind that, the schematics on their website show completely separate 145V supplies for the output stage.

OTOH, the schematic for the input power supply shows both +400V and +/-190V being obtained from the same transformer. That is impossible with the ground reference at the CT of the transformer. Either the schematic is wrong or...?

If you are talking about something else, then you'll need to provide a schematic or a link.

-- Dave

[agent.5]

If you really want to just use one power supply, you need a very big choke. I think it is better and easier to just build 2 power supplies.

http://www.tubecad.com/december2000/page15.html

[woody]

Dave,

If you look again the raw supply has a tap labled 145v+ and
a tap labled 145v- but in reality this is one 290v supply.

[poynton]

Originally posted by woody
Dave,

If you look again the raw supply has a tap labled 145v+ and
a tap labled 145v- but in reality this is one 290v supply.

The diagram shows 2 identical supplies of 145v each.

The labels refer to the + and - connections only and do not imply that the supplies are 290v.


Andy

[poynton]

Originally posted by agent.5
If you really want to just use one power supply, you need a very big choke. I think it is better and easier to just build 2 power supplies.

http://www.tubecad.com/december2000/page15.html

The use of a split primary transformer as a 'balanced choke' is interesting.

However, would not the use of 2 of these ( in effect 4 chokes ) negate the idea of OTL amps i.e. No transformers!

The circlotron has in effect become 2 cathode followers with choke loads.


Andy

[agent.5]

Originally posted by poynton



The use of a split primary transformer as a 'balanced choke' is interesting.

However, would not the use of 2 of these ( in effect 4 chokes ) negate the idea of OTL amps i.e. No transformers!

The circlotron has in effect become 2 cathode followers with choke loads.


Andy

Circlotron was originally designed by EV WITH output transformers.

[Tweeker]

Hi Andy,

However, would not the use of 2 of these ( in effect 4 chokes ) negate the idea of OTL amps i.e. No transformers!

Theres going to be a transformer in the PSU at some point (even in line op death traps), unless your running off battery power. Running off the mains, I much prefer having chokes and transformers in it.

[poynton]

I am interested in using a circlotron with a single supply. [In fact, the thing which has so far put me off building one is the complexity of the PSU.]

The use of chokes / transformers looks neat but I have a question that someone may be able to answer.

http://www.tubecad.com/december2000/page15.html
http://www.tubecad.com/december2000/page16.html

On page 16, the article refers to using a split primary / split secondary transformer. [115-0-115 / 115-0-115]

Does the phase of the connections matter ?



Andy

PS Has anyone tried this method?

[Yvesm]

This method was used by N.H.Crowhurst in its famous "Unity coupled" amplifier.

It's no longer a Circlotron in that sense that anodes and cathodes windings of the OPT become independent and are center tapped.

The beauty of the Circlotron is to use the same single winding for both cathodes and plates loads.
The center tap is just the reference for the drive signal.
You cannot have a better coupling, even using bifilar winding as McIntosh did

But the price to pay is a dual FULL FLOATING PSU.

Yves.