What circuit and tube to be used

[ckwong99]

Hi All,

Can anyone give me a suggestion about my second hand o/p transformer is single-ended around 20W and Z=1K , which kind of power tube should be used and what kind of circuit suit for it ?

CK

 

[firechief]

HI CK
Please help me by providing the specifications for the transformer. Also Manufacturers name, model number. I need more information to get started. With this information provided you are much more likely to get suggestions. Also good luck with the project.
Bob

 

[wakibaki]

Are you thinking about an instrument (guitar) amplifier?

Most people prefer matched O/P transformers for Hi-Fi.

w

 

[ckwong99]

Thanks to your questions.

Sorry, they are second hand o/p dismantle from PWR amp also they are not a commercial product. Seems a DIY thing made in China / Taiwan with an external iron box enclosed.

I want to make a single-ended PWD amp around 10W.

There is some description

Primary :
Red color wire connected to transformer with "B" marking
Yellow wire connected to transformer with "P" marking

Transformer body :
Have string "LM-1K-25F" & Zp : 1Kohm

Secondary :
Have 4 wire marked as 0 / 4 / 8 / 16 ohm

 

[azazello]

Hi!
If You'l build SE aprox. 8-10 wts, You can use russian 6S41S - Ri=300 ohm /6С41С/ with Ia= 100-120 ma, and wire diameter primary coil must be aprox. 0.3 mm!!....Or
2 parallel 6S19P - Ri=150 ohm /6С19П/, with Ia=60 ma each,
or 2 par. ED8000 - http://www.tubedepot.com/nos-ed8000.html
Preamp. EF861, E180F. If You interest, I can give You a schematic - 6S41S & EF861 !
But first, You must measure wire diameter!!

 

[ckwong99]

However, I had already bought this pair of output transformer. Not sure they suit for your power amp circuit ?

This is there descriprtion

Primary :
Red color wire connected to transformer with "B" marking
Yellow wire connected to transformer with "P" marking

Transformer body :
Have string "LM-1K-25F" & Zp : 1Kohm

Secondary :
Have 4 wire marked as 0 / 4 / 8 / 16 ohm

 

[azazello]

You can try 2 of ED 8000 or 6S19P, Ia=80-90 ma per channel, and EF861.
It's will be OK.

 

[ckwong99]

can you send their 8000 and 6S19P circuit for my reference ?

 

[azazello]

OK! I will....
You also can use 6P45S /6П45С/ - Ri=200 ohm, Ia=80-90 ma.
Very linear tube for TV and Hi-End !

 

[azazello]

You have an Email....

 

[azazello]

Parameters ED8000 and 6S19P are close.

 

[ckwong99]

1k/50w output transformer for which type of power amp

Can anyone one tell me 1k o/p transformer for which type of tube power amp design ? I want to DIY a single end or push pull class a power amp.

 

[jazbo8]

Why 1k?

 

[ckwong99]

1k ohm. My friend give me ,he pick it from the old tube power amp

 

[jazbo8]

Can you take a photo of it? We need to see the wires and the size of the transformer.

 

[ckwong99]

Ok. Later today. Thx for your attention again

 

[artosalo]

Can anyone one tell me 1k o/p transformer for which type of tube power amp design ?

Possibly a Circlotron. I have used 1k and 1k2 OPT with these.

 

[audiowize]

Is it a gapped transformer for single ended use, or a push-pull transformer? How large is it?

 

[danFrank]

It's "guess the transformer" time again!!!

I say it's a opt trans from a McIntosh MC30 or MC40.

This is exciting!!!

 

[Shef]

It's "guess the transformer" time again!!!
. . .
This is exciting!!!

almost sounds like X-mas )) my guess is that's some German piece