How to wire up Audio Matching Transformer?

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Hi, I've got some 600:600 Audio Matching Transformers that I'm hoping to use in a project (a mixer).

Here is the diagram printed on the item:
Code:
(Pri 600)       (Sec 600)
Pin 1 ---+ | +--- Pin 4
         | | |
         | | |
         | | |
Pin 2 ---+ | +--- Pin 5
           |
         Pin 3 (C.T.)

I've wired one into an audio channel. I have the input wired to Pin 1 and the output wired to Pin 4. I have the ground for both the input and the output wired to Pin 3.

I can hear sound clearly coming through, but it is attenuated quite a lot, and it sounds like it is going through a high-pass filter. I have learned that many transformers are designed to filter out certain frequencies, but this is not noted anywhere on the transformer itself, or in any specifications I can find for it.

Have I got something wired incorrectly? I've searched for a clear explanation of this with no luck.
 
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The product is:
TOROTEL AUDIO TRANSFORMER TF5R17ZZ 600/600 OHMS

No data I have found on transformers in this series refers to frequency filtering. This "lack of information" and the diagram on the transformer itself which I have reproduced above, is all the information that I have been able to find.

rs
 
Hi,

According to your pin out input is between 1&2, output between 4&5,
3 is overall screen. You can float the input (usually) or the output.
Floating the inputs will prevent earth loops (hum) developing.

Make sure you don't wire them to be phase inverting, you can
get signal cancellations if you do and start mixing the outputs.

rgds, sreten.

Can't make out the very murky picture on e-bay :
TOROTEL AUDIO TRANSFORMER TF5R17ZZ 600/600 OHMS | eBay
 
Thanks for the help folks.

For some reason I had the idea that connecting one input and one output was sufficient, though now I understand that was incorrect.

I tried floating the input but without its ground wired to the CT, I was getting lots of hum.

Another question: My understanding is that the output pins will be phase-inverted from each other. My circuit is not a balanced circuit, so I'm thinking I'll only need one or the other of the outputs. Should I ground the other one, or tie them together?

Thanks again for any help on these extremely basic questions.

rs
 
Hi,

If you can't float the input with no hum, your doing something wrong.

There is no reason to wire it as phase inverting, as in my warning.

As DF96 states, why are you using them and for what purpose ?

If there is no problem to fix, 1:1 transformers have no useful purpose.

rgds, sreten.
 
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