SEPP output transformer
 

Dear All,

I found a SEPP circuit from an old magazine of year 1966 as Fig-1 shown. It was using an output transformer which has two groups of primary windings. Can anybody explain what is the different if using a single winding transformer as Fig-2 and the advantages and disadvantages in comparison?

Thanks

Patrick

Fig-2

Fig. 1 shows 2 windings, each with screen current drawn through it in opposite phase, therefore the DC cancels.

AC wise, it's the same as Fig. 2.

But there's a hair bit of DC in fig. 2 that appears to be some FB method to the driver tube.

Cheers!

you may be able to get a transformer with a centre tapped primary and then cut at the centre tap so you have the two half's.

(like them diy's would do in thems days)

Dear Geek,

Thank you for your response. Can you tell me more details of the transformer winding topology of both?

Dear Pointy,

Thank you for your advice, I intend to wind the transformer myself. Any idea can tell?

Regards

Patrick

Hi Patrick,

Not any more than I have really... I haven't studied or explored parafeed transformers that much, outside of making a pair for a headphone amp that used neither of these topologies. So I shall derfer to someone who may know more.

Cheers!

Dear Geek,

However, thanks a lot.

Regards

Patrick

Hi Patrick !

I did a similar project.

http://mitglied.lycos.de/manta/proje...o/cheapo_9.gif

Here are some pics about it.

regards, Simon

That parafeed cap seems very small. When i messed about with parafeed I always used something around 4uf.

What power where you getting?

Looks like one of my messy builds.

Shoog

Re: SEPP output transformer
 

[QUOTE]Originally posted by pat49hk
[B]Dear All,

I found a SEPP circuit from an old magazine of year 1966 as Fig-1 shown. It was using an output transformer which has two groups of primary windings. Can anybody explain what is the different if using a single winding transformer as Fig-2 and the advantages and disadvantages in comparison?

Hi,
Fig1 is right for pentodes fig 2 is only work for triode.the two resistor of g2 will eat most of the output power.
Cheers!
Singh