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Phil Allison[_3_] Phil Allison[_3_] is offline
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Default Mystery transformer

"GRe"
"Phil Allison"

You need a THD meter to make sense of what matters and what does not.


Input f/V/THD Output THD (600ohm terminated)

1kHz/1.0V/0.075% 0.082%
1kHz/3.6V/0.086% 0.101%

3.6V is the max. output for the audio generator.



** You need to use a much lower frequency.

Transformer non linearity is concentrated at the low end of the audio
band.


I used the function generator HV-output(600ohm) for this test.

Input f/V/THD Output THD (600ohm terminated)

200Hz/10V/0.036% 0.049%
100Hz/10V/0.037% 0.077%
50Hz/10V/0.037% 0.170%
25Hz/10V/0.036% 0.442%



** No "function generator" I ever heard of has THD figures as low 0.036%.

Post a link for the one you have.



PLUS it is crucial the source impedance be low - like 50 or 100 ohms.


In this case it does'nt seem to make a difference using the function
generator 50ohm or 600ohm output,



** Something is very fishy with your testing and that generator.


Easy way is to use one channel of a good hi-fi amplifier to buffer the
output of the generator and drop the impedance to near zero.


Only handy in the living room, not on the bench.



** Stop being such a PITA ****.

I posted HOW to do it - whether YOU have such an amp handy or not is
YOUR problem.

What a tedious **** head.



.... Phil