How can I use UTC A22 at OPT in pre-amp?

[car]

Dear all,

I got a pair of UTC A22 (500:500/125). I want use it as the output transformer in pre-amp. However, I don't know how. Any workable workaround method to use it in 6SN7 pre-amp....?

Or any suggestion to use this transformer?

An externally hosted image should be here but it was not working when we last tested it.

Thank you.

Happy Diy
Car

 

[Jozef]

Well,
Why not.First try to found 7233 tube.
Make a CCS load for it at let say 25mA.
Use parafeed linestage configuration with
A-22 1:1 set-up.
That be simple stage OK with CDP.
Joe

 

[car]

Hi Jozef,

Thanks for your reply. I'm newbie in DIY Tube Amp, I don't have much experience on CCS and parafeed linestage. Do you know any example available in the web?

BTW, may I use 6SN7 instead of 7233?

Once again, thanks Jozef..

Happy Diy
Car

 

[Jozef]

Hi Car,
You A-22 it's only 500 ohm so you can't use it with 6SN7.
Plate resistence of 6SN7 will be around 8 kOhm that mean you needed
at lease 15 kOhm trafo to work with this tube.
7233 is a regulator triode with plate resistence around 230 Ohm.
This only tube I know that maybe work with 500 Ohm trafo.
About CCS and parafeed I proposal you start with DIY Forum
search engine.
Good Luck !!!

 

[car]

Hi Joe,

Thank you very much for your reply....
For ccs and parafeed, i will try to search in this forum.....

Thanks....


Happy Diy
Car

 

[fdegrove]

Hi,

Hmmm...
Using a tube with a µ of 4 and a Zo low enough to kick but the lowest impedances I wonder why one would want an OPT to couple it to the next stage?

I could think of some uses but in most cases they just seem like a forced implementation to me.

Anyway, do as you see fit...

Cheers,

 

[fdegrove]

Hi,

Ooops...And yes, this looks like a PP xformer to me so you'd still have to parrot feed it ( parallel feed).

Put them back into the junk box I'd say...

Cheers,