RE: Terry's trigger circuit Q's

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

Original poster: "J. B. Weazle McCreath by way of Terry Fritz <twftesla-at-qwest-dot-net>" <weazle-at-hurontel.on.ca>


Hello coilers,

I too have been playing around with variations of Terry's controller
circuit for the triggered gap.  I first started out with copying as
close as I could the circuit that Terry was using, but I found that
I got smoother operation with a "dummy load" of roughly 100 ohms as
opposed to the 25 ohms that Terry found to work on his setup.

Like him, I didn't care for the idea of wasting all of that power in
a couple of resistors (electric furnace elements in my case) so I did
a search of some postings of a few weeks ago and I found one possible
solution at this site:

http://www.neonshop-dot-com/neonweb/nn/tdorr17.html

My dimmer was a Leviton "Trimatron" 600 Watt unit that had only the
triac, a variable resistor, and a capacitor.  I followed the mods as
described at the above mentioned site, save for using a 2K resistor
in place of the 3500 ohm one shown, and it seems to fire my GM HEIC
trigger transformer quite nicely.  I haven't ran it with the coil as
yet because I'm waiting for some protective MOV's from Terry before
I give it the acid test, but it does at least fire the trigger well,
and does away with those big resistors or heating elements.

When the MOV's arrive, I'll do a full power test and post my findings
to the list.  I suspect it will work just fine, however.


73, Weazle, VE3EAR/VE3WZL

Listening: 147.030+ and 442.075+
E-mail:    weazle-at-hurontel.on.ca
           or ve3ear-at-rac.ca
Web site:  www.hurontel.on.ca/~weazle