BUWEPS Trafo info/uses?

Gents,

I was recently at a local surplus store and came across a BUWEPS(Navy) transformer made by Peerless Elect. Prod.  It's 2 1/2" x 1 1/2" and the number on it is 1563737H with a 9 small pins the same spacing as a 12A**tube and 2 threaded post soldered to secure it. 

resistance is as follows:
pins 1 to 3 - 1.4ohms
pins 1 or 3 to pin 2 - .8ohms

pins 5 to 6 - 73.5ohms
pins 5 to 7 - 142ohms
pins 6 to 7 - 67.8ohms
pin 9 - case

I ran a sweep through it and was extremely flat exept for a 1dbish bump from 10k to 13k. 
I couldnt test any specs before I bought it but saw it was made by Peerless and picked it up. 

So, any thoughts on what this trafo could be used for? 

Many Thanks, Nathan

that's sounding kind of 30-50 to 1-2K ish.  Did you measure gain?  How did you have the unit loaded?  Input source Z, load Z, etc.

I need to spend more time learning to measure trafos and will do so with ones I know the value of to get a perspective.
I don't have much in the way of test gear, but here's what I tried out. 

Signal chain:  1k, 1v P2P signal gen. to 600:150 trafo to pins 1 and 3 on test trafo. Test equipment is an rms multimeter and Visual Analyzer pc based oscope with outboard buffer circuit I copied.

On the output of the 600:150 I measure .4v ac on my meter not connected to peerless. 
Using the VA software I measure a -3.5db level at 1k.

When I connect the trafo I measure .014v ac on pins 1 & 3 and I get a level of -24db

On pins 5 and 7 I measure .19v ac and -12db at 1k.

I know I need to spend alot more time on theory, testing, etc - been mostly just learning as I go.

Does this info shed more light on the specs of this tranfo?

THanks for your help, Nathan

if I'm reading you correctly, it sounds like the transformer is giving 12 dB of gain.  So, plug that into the ratio math, and you get your ratio.  You are feeding signal into a very low impedance primary, and likely loading down the generator.  Run signal the other direction, and leave the 600:150 out of the picture.  Numbers probably come out the same, but might not.  The ranges I quoted before are reasonable guesses, so see if the ratio falls into the same categories.  That tells you roughly what the intended range is.  Then retest by using series resistance equivalent to the guesstimate impedance of the high side (5-7) between generator and winding.  If you know generator output Z, subtract that from the resistance used.  Then shunt load the low side (1-3) with the guesstimate resistance, then measure the frequency response.  Alter the resistance values while looking at changes in response, and see where performance falls off.  That's a good indication of useful operational range. 

Excellent!  Exacltly what I needed to know.  I wasn't sure the output imp. of my signal generator so I used the 600:150 as a guestimate to present a lower impedence to the trafo.  Appreciate your time, Doug!

Regards, Nathan

The nominal audio impedance is -roughly- 10 times the winding resistance.

(Or: winding R loss is 1/10th of the total. If loss were higher, that would suck. If loss were lower, it would cost too much. So depending on design goals, 5 to 20 times DCR, and "10" is a good first guess.)

So your 1-3 winding is near 14 ohms. No wonder your 600:150 source was sucked-down.

And your 5-7 winding is in the area of 1,500 ohms. I would drive that with a "150" source and see what came out the other side.

There IS something odd. Winding R suggests 15:1500, a 1:10 turns ratio. But your voltage numbers suggest a 1:4 ratio. This is not an absurd discrepancy, but makes the nominal design impedance even murkier.