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Old 06-15-2011, 05:19 AM
Farmhand Farmhand is offline
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Join Date: Jun 2010
Location: Australia
Posts: 3,389
OK I had some better results, for a while before I decided to improve my gate drive ( the IC was damaged ) after getting a nice square drive signal the circuit became very efficient but when i went for more power the mosfet failed. I had to remove the protection neon because it was glowing purple.

I guess I pushed it too far. More abrupt switching caused an awefull lot of voltage at the primary cap with less than 0.3 uf. When I go above 250 Ma on the input everything lights up good but the mosfet gets really hot. I'm trying to work out what I'm doing wrong.

Here is some pics before I screwed the power up and fried the fet.
http://wv0v9q.bay.livefilestore.com/...009.JPG?psid=1

Cfl connected to top and ground.
http://wv0v9q.bay.livefilestore.com/...007.JPG?psid=1

It can light two neons in series by holding one leg and touching the other to the top. It burns my finger after a bit.
http://wv0v9q.bay.livefilestore.com/...013.JPG?psid=1

And it will light up a 5mm LED on the receiver across the room trough a FWBR and 270 Ohm resistor.
http://wv0v9q.bay.livefilestore.com/...015.JPG?psid=1

I have parts and am designing a new circuit to drive the mosfet's, I might try to use two alternately to reduce the stress on them. Not sure yet what I will come up with.

I think the noise from the transmitter affect's the circuit at a certain point and causes erratic behavior and double pulsing, like this.
http://wv0v9q.bay.livefilestore.com/...004.JPG?psid=1

Sketch pad and Breadboard time.

Cheers
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