Does anybody know this transformer...

It's from a local PA store, the owner says they are from an old Neumann console... (he's got a whole bunch of them).
Has anybody seen one of these before?

More pics here:
http://www.partymommsen.de/pepe/im000045.jpg
http://www.partymommsen.de/pepe/im000039.jpg
http://www.partymommsen.de/pepe/im000044.jpg

Thanks a lot
Stephan

That looks like the bowl off my water pipe!
:razz:

Might be mic input,

they look VERY small. Freq. response might not be that good. you should test them on a scope.

I have trafos in a similar can. They came from an old RTF console and are mic input. Wound on L core, not interleaved.
Can you tell me exactly diameter of the can. Also try to open it (take off this yellow tape) and take inside pics to see if they look the same. Can you measure inductance?

I'm sure Mic Input (I have some Sennheiser Transformers looking like that).
But all Neumann Mic Pres I know did not use this one - would be interesting to know the Modell Number (or the place it was installed).

Hi!
Thanks for your thoughts...yeah it's really small the can is about 1.9cm diameter and height.I managed to open the case - look here (not the best pics, sorry):

http://www.partymommsen.de/pepe/im000047.jpg
http://www.partymommsen.de/pepe/im000049.jpg
http://www.partymommsen.de/pepe/im000052.jpg

The core is a laminated E type. I estimate the coil to be of 5mm length and 7mm diameter.
The inductance (measured with a cheap LCR meter) on one side is 1.5H, on the other it is out of range (>20H). Corresponding DC resistances are 103ohms and 5.4 kiloohms.
Can I deduce from these values that the ratio is about 1:7.4?

Unfortunately I don't have a scope...does it make sense to measure the frequence response with a computer based oscilloscope (like audio Tester)?

Rafafredd suggested it is a Haufe transformer - would make sense with both Sennheiser and Neumann, no!?

Thanks again
Stephan

[quote author="boodthee"]
Can I deduce from these values that the ratio is about 1:7.4?
[/quote]

No. DC resistances tells little about turns ratios, as different type of wires are probably used for pri/sec. Also the outer layers are using more length per turn than the inner layers.

You will need to input a known signal, say 50mV/200Hz, and measure what comes out. The ratio between the voltages will be your turns ratio.

If you have 1H5 at the primary side, it should be safe up to some 600 Ohms primary source impedance.

The output impedance will then be the turns ratio squared times 600 Ohms

Jakob E.