Ahhh, that explanes a lot.
If your low frequency response is good you have a nice transformer.
If your low frequency response is good you have a nice transformer.
That 'brand X' has a 55KHz pole, 5dB isn't it? Did you try reversing polarity?
What were your test conditions?
- With terminated transformer secundary?
- Was the output of the generator terminated with it's characteristic output impedance?
Of course i did reversing, but that was not confirmed what the manufacture say. It is better reversed but all depends on the load.
btw, the biggest problem of this transformer was not the high frequencies but the low frequencies. To less induction for small (it was line stage interstage 1:5) signals.
btw, the biggest problem of this transformer was not the high frequencies but the low frequencies. To less induction for small (it was line stage interstage 1:5) signals.
Source 10KΩ load1500Ω, no dc
About using square waves, they are very useful to see if the transformer is well made or not. Resonance free or not. But you can do also with a sinus if you test till 1MHz.
About using square waves, they are very useful to see if the transformer is well made or not. Resonance free or not. But you can do also with a sinus if you test till 1MHz.
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I must make my previous post more clear. As far as I remember discussion was bout square-wave test of an audio transformer at LOW frequencies. That test is really useless, completely.
Test at several KHz does make some sense. Overshoot size is correlated to stray capacitance (please correct me if I'm wrong here), and ringing - to resonance because of combination of stray capacitance and leakage inductance.
Yet its better to just measure lowest resonant frequency with sinewave. If its around 50 KHz or even below - Houston, we've had a problem.
If you mean with compleet useless that using a sinus is a beter way to test the low frequency range, i agree, but there is information in low frequency square waves.
I prefer resonance >200kHz or even better, well damped.
I prefer resonance >200kHz or even better, well damped.
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