Re: Flyback questions

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Jan Florian Wagner by way of Terry Fritz <twftesla-at-qwest-dot-net>" <jwagner-at-cc.hut.fi>


> I finally got a xfrmr without a diode. It does indeed produce AC.
However, one
> end of the secondary is hot, and the other only has a few volts.

Could be that the one end of the sec is grounded, and you get those "a few
volts" from a feedback winding (also internally grounded)? 

> And this is a basic question I shouldn't have to ask, but if I am getting AC,
> my meter should read 1/2 of the true voltage or less on the DC settings, no?

Probably depends on the sampling freq of the DMM. And it won't be 1/2 of
AC. Very likely jumps around between different values that are <<V_ac. (at
least that's the case with the DMMs that I've come accross)

Keep in mind that typical DMMs can not handle frequencies above a few kHz
very well. Freq counter works ok there, but the error for voltage and
current measurements will increase as the freq increases.
(hmm, I would've thought that the "AC" setting will just rectify the
AC input. That doesn't seem to be the case, though... Or? At least my
DMMs screw up above 3kHz already, plus the piezo beeper starts to
resonate)

> And the meter should read nothing on the AC scale if DC is applied, correct?

Yup.

cheers,
 - Jan

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