Re: SSTC problems1 (no its not a PlasmaSonic ;-))

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

Original poster: "Jim Mitchell" <electrontube-at-sbcglobal-dot-net> 

I have ruled the problem out to be in the section that receives feedback
from the coil.  The reason the coil is running crappy is because the 555
timer is running it, instead of the feedback.  It seems the feedback doesn't
have enough "oomph" to kcik in and take over the 555.  So I removed the 555
and banged on the antenna with a screwdriver.  Neon bulb on the breakout
point flickered and I hear a 60hz hum in the GDT section, and thats it.  I
will try more filtering on the input and see if I can get it to run with out
the 555.

Regards - Jim Mitchell


----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Monday, January 26, 2004 6:48 PM
Subject: SSTC problems1 (no its not a PlasmaSonic ;-))


 > Original poster: "Jim Mitchell" <electrontube-at-sbcglobal-dot-net>
 >
 > Hi,
 > Today I finished my Feedback SSTC, It is based on Aaron and Justin's
 > feedback SSTC design, I am using a full bridge of FDH44N20 MOSFETS and a
 > 18X 4.25" secondary wound with 30AWG.  After getting much help from Steve
 > Ward via email, I finnaly got to the first testing phase.  I tuned the
 > potentiometers right in the reigon that I saw the biggest swing on the
 > scope.  I had a neon bulb attatched to the breakout point, and at about
10v
 > input, the neon bulb striked.  I brought it up to 150v and the neon bulb
 > got very bright and I coul hear 60hz buzzing in the bridge.  Now I though,
 > well I'll reverse the primary turns.  So I reversed the primary turns, and
 > STILL the output was the SAME the neon bulb was lighting to the same
level,
 > no increase and no breakout.  I am afriad my MOSFETs aren't being driven
 > into saturation by my gate driving circiutry.  Is there a way to test if
 > the MOSFETS are saturating?  Has anyone else experienced this and knows
the
 > remedy?  Help!
 >
 > Regards - Jim Mitchell
 >
 >