I rigged up an external signal generator so I could check inductance of a transformer at different frequencies.
That is, I can null out the General Radio impedance bridge at different freequencies to see how the inductance and Q changes.
This was the missing link as far as blueprinting transformers, as now I have a better illustration of what is happenning at the low end.
Before, all I had was a straight line that went down to about 1 hertz.
Well, if every transformer I test has the same line, it really does not tell me much.
But now, I have a "fingerprint of the low end response.
This, combined with the high end freq response provides a more complete picture of the transformers response.
Here is a graph showing a UTC Black A-10 vs a light gray A-10.
Inductance is on the left axis.
Frequency is on the bottom axis.
I added a few "Q" figures also. Enjoy!
cj
That is, I can null out the General Radio impedance bridge at different freequencies to see how the inductance and Q changes.
This was the missing link as far as blueprinting transformers, as now I have a better illustration of what is happenning at the low end.
Before, all I had was a straight line that went down to about 1 hertz.
Well, if every transformer I test has the same line, it really does not tell me much.
But now, I have a "fingerprint of the low end response.
This, combined with the high end freq response provides a more complete picture of the transformers response.
Here is a graph showing a UTC Black A-10 vs a light gray A-10.
Inductance is on the left axis.
Frequency is on the bottom axis.
I added a few "Q" figures also. Enjoy!
cj