Re: Help! My Coil Blew Up

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

Original poster: "S.Gaeta" <sgtporky-at-prodigy-dot-net> 

Thanks Bob,

I have the 15 volt zeners on the gates of the fets. In fact the FET that
blew apart took one of them with it! Yea, the 12 volts is a real life saver.
Nothing got hot when I ran it that way.

I ran the circuit with an external function generator when I was first
checking out my gate waveforms. I could get 50% duty cycle that way. When I
used the 555 as a signal source just to check things out, I couldn't get
anywhere near 50% and the drivers ran hotter(I didn't have the fans hooked
up at the time).

I have uploaded all the schematics that I used to
http://community.webshots-dot-com/photo/113763981/116381344aERret
and put them all together on one page. Its better than linking to this and
linking to that, and now I can print it all on 11x17!

Sue
----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Thursday, February 05, 2004 10:17 AM
Subject: Re: Help! My Coil Blew Up


 > Original poster: "Robert Jones" <alwynj48-at-earthlink-dot-net>
 >
 > Hi,
 >
 > I think you may need to give people a little more time to respond.
 >
 > I don't have any direct experience on SSTC.  Your failure sounds like it
 > could be caused by a lot of things.
 >
 > I would expect the bigger the toroid the better to get your frequency
down.
 > Your frequency does seems high that maybe causing the unexpected heating.
 > In any case if the fets are getting unexpectedly hot it indicates you have
a
 > problem. I think you need clamping zeners too. Stick to 12v in till you
have
 > every thing looking right unless you have a bucket of new fets.  I also
 > suggest you run it of an external oscilator untill you have it all checked
 > out and check the signal from your pick up.
 >
 > Your link down loads a file with an unknow extension??
 >
 > Bob
 >