suggested uses for the following trafo's

[ToobieSnack]

Hey,
i have the following trafo's available for projects:

Triad 3213
magnacord 6910-15
UTC a-21
UTC 41922 (black...from a gates gr-91 remote)
Altec/peerless 15095-a (the red one)

that triad and the magnacord were in a magnacord mic pre/amp (PT6-j) the mag trafo is probably triad too.
the mag trafo is a plug in type.
how do i ohm out this trafo to see what it's pri and sec are? (stupid question ..i know...sorry but i thought there may be some info that will be helpful )
thanks
Toobie Snack

 

[bcarso]

"how do i ohm out this trafo to see what it's pri and sec are?"

The ohmmeter will help you find what pins are what if it's not printed on the case.

To get an idea of the turns ratio you need to put a small signal, say at a kilohertz, into one of the windings and look at the others. Measure the voltage you are putting in and measure what you see coming out of the other windings. The ratio of voltages is the turns ratio. This doesn't tell you what impedances the trafo is designed to work best at, but an educated guess at that for one winding will get you started. The impedances "seen" at the other windings will be about that guessed one times the square of the particular turns ratio.

Or, maybe somebody in here just knows what these are already ;-)

 

[Mark Burnley]

Transformer datasheets abound at CJ's site:

www.vacuumbrain.com

When he ain't hacking iron, he's scanning crumbling databooks!

:green:

Mark

 

[ToobieSnack]

the UTC a-21 is 500 ohm /500ohm
the altec peerless is 600 ohm / 15,000 ohm
I can't find info on the others
all the traid stuff seems to have the prefix HS-XX
I don't see anything for a triad 3213.
the magnacord who knows...
and the older (black) UTC has a older numbering scheme.... (not the typical letter plus number) how can I find info on trafo's like these?
thanks
TS

 

[PRR]

> This doesn't tell you what impedances the trafo is designed to work best at

When totally clueless, assume about 10 times the DC resistance.

SE output that has to carry huge DC current may be about 5 times DCR.