solid state flyback driver

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

Original poster: "Mr Gregory Peters by way of Terry Fritz <twftesla-at-qwest-dot-net>" <s371034-at-student.uq.edu.au>

Hello all,

I've come up with an idea for a flyback driver. Let me know what you 
think.

I was having a look in a regular desktop computer 230W SMPS. This is 
actually a pretty nifty little device :) It uses a PWM chip I thought I 
had never heard of, but after a quick search I found out it was 
actually a relabled TL494. So basically, I figured I could replace the 
resistor that sets the frequency of the TL494 for a POT, and bypass the 
diodes that rectify the HF transformer output. This would give a dandy 
little 200W, variable frequency, 5v/12v power supply. Advantages are: 
runs directly from a power socket, excellent inbuilt circuit 
protection, cheap as peanuts from a dumpster. 

The only reason I can see that this may not work, is that the 
transformer is meant to operate at either 50 or 100kHz, and may not 
have sufficient windings on the primary to operate at the lower 
frequencies for powering a TV flyback (15kHz or so). Ideas?


Cheers,
Greg Peters
Department of Earth Sciences,
University of Queensland, Australia
Phone: 0402 841 677
http://www.geocities-dot-com/gregjpeters