Where can I get transformer for this (USA)?

[bondul]

Hallo! I am a new diyer. Trying to build PSU for my preamp tube. It requires 3 secondaries output. So far, I need to combine 2 transformers (based on edcor, hammond and antek design) . I'm wondering if anyone know where to buy 1 transformer in USA that can supply all 3 secondaries output.

Also, is there any company offering transformer kit? I am willing to learn.

I am attaching the scematic. All is the same but the primary (input) should be 115V (US).

Thanks!

[bondul]

Originally Posted by bondul

Hallo! I am a new diyer. Trying to build PSU for my preamp tube. It requires 3 secondaries output. So far, I need to combine 2 transformers (based on edcor, hammond and antek design) . I'm wondering if anyone know where to buy 1 transformer in USA that can supply all 3 secondaries output.

Also, is there any company offering transformer kit? I am willing to learn.

I am attaching the scematic. All is the same but the primary (input) should be 115V (US).

Thanks!

This is my attachment with bigger picture

[jackinnj]

If you're not drawing a lot of current for the regulated supplies, you can wind the secondaries on the existing torroid without a lot of difficulty -- by taking one of the 6.3V windings and adding to it.

I've used transformers from discarded Eico, Heath and Knight test equipment bought at hamfests an online. A lot of these devices used 6X4 rectifiers, etc., etc.

[bondul]

Originally Posted by jackinnj

If you're not drawing a lot of current for the regulated supplies, you can wind the secondaries on the existing torroid without a lot of difficulty -- by taking one of the 6.3V windings and adding to it.

I've used transformers from discarded Eico, Heath and Knight test equipment bought at hamfests an online. A lot of these devices used 6X4 rectifiers, etc., etc.

Thank You for the information!
Can you give me link to some literature to do that.

[tauro0221]

Hi,
Did you check Antek AS-1T250? This have 3 winding 250 volts and 2 winding 6.3 volts. At least you have 2 in one. Also did you talk to them they may make one custom made for you.

[kevinkr]

Edcor will build to order exactly what you need for a very nominal fee, although there is a $40 set up charge to make it. They may also have something close in their catalog already.

You could use this one with an additional transformer for the 15V supply.. http://www.edcorusa.com/p/588/xpwr001_120

[jackinnj]

Originally Posted by bondul

Thank You for the information!
Can you give me link to some literature to do that.

You can do something like this -- wind 10 turns of (for example) insulated #18 wire around the torroid. You can use a signal generator to supply a relatively low voltage to the primary of the transformer.

Measure the voltage coming off the 10 turns, measure the voltage the voltage of the 6.3VAC winding. I'll let you do the maths -- the ratios will tell you how many turns of #18 wire you'll need to bring the 6.3V winding to 15VAC. When incorporating the additional turns you need to keep going in the same direction as the 6.3VAC

[bondul]

Originally Posted by jackinnj

You can do something like this -- wind 10 turns of (for example) insulated #18 wire around the torroid. You can use a signal generator to supply a relatively low voltage to the primary of the transformer.

Measure the voltage coming off the 10 turns, measure the voltage the voltage of the 6.3VAC winding. I'll let you do the maths -- the ratios will tell you how many turns of #18 wire you'll need to bring the 6.3V winding to 15VAC. When incorporating the additional turns you need to keep going in the same direction as the 6.3VAC

I suppose I need to add wire on the existing 6.3V to make it 15V?
Do I need to discard the 6.3v winding and restart from the beginning or just add (solder and isolating the existing 6.3v winding with new wire) until come up with 15V?

Other topic: what do you use to make it magnetic shield?

[bondul]

Originally Posted by tauro0221

Hi,
Did you check Antek AS-1T250? This have 3 winding 250 volts and 2 winding 6.3 volts. At least you have 2 in one. Also did you talk to them they may make one custom made for you.

I am sure this is very dumb question:
"If I want to modify 6.3V to 15V, I need to add winding. Instead: can I take one of existing 250V, reduce the winding and make it to 15V?"

[CBS240]

Also, is there any company offering transformer kit? I am willing to learn.

Yes. Here is a company I have used before. price includes shipping and mounting hardware. You have to supply the magnet wire for the secondary yourself, but for the 250VAC winding you would use smaller guage wire, isulate it with the supplied polypropylene film plastic wraping and then add the lower voltage secondary windings on top.