Re: Flyback Pinouts

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

Original poster: "Marry Krutsch by way of Terry Fritz <twftesla-at-qwest-dot-net>" <u236-at-earthlink-dot-net>

Hi Allan, All,

	Thanks for the suggestions.  I finally figured it out, and found that
the primary is not the winding with the lowest resistance, which you
said.  There appear to be components INSIDE the flyback, which may make
up some sort of feedback system for the driver.  I shorted together the
two pins that were arcing to each other, and the flyback began to
perform normally.  I'm not sure if the coil I'm using as the primary is
the "real" one, but the output sure looks good :-)).  I get nearly 1"
sparks out of it (to ground) and it will "power arc" at 1/2", all with
12v at 1.5 amps (18w) in.

	All my flybacks perform best with about 10 kHz input, and the pulse
width as long as I can make it without my pulse generator doing strange
things (when the pulse width is made longer than what is possible for a
given frequency, it drops the output freq. to 1/2 the previous value). 
Increasing the input freq. to the flyback (and adjusting pulse width
accordingly) makes the output decrease slowly.  Below 10 kHz, the longer
pulse width available just saturates the flyback, and output remains the
same, but with much higher current input.

Thanks again for the help,
Winston K.

Tesla list wrote:
> 
> Original poster: "Allanh by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<allanh-at-starband-dot-net>
> 
> 10 Khz is a bit low for the flyback. The pins you are using are probably not
> the right ones.
> The ones to look for usually are isolated from the others with at least one
> empty space. The resistance between the correct two pins is often higher
> than any others. There will be no connection between the input winding and
> any other
> pins. If you can get your hands on a schematic, if would reall help. Look at
> the circuit board and trace the runs that connects to the original drive
> transistor and that will give you a clue.
> 
> hope this helps.
> allan