Two Toroid Test

From:  D.C. Cox [SMTP:DR.RESONANCE-at-next-wave-dot-net]
Sent:  Tuesday, June 23, 1998 6:32 AM
To:  Tesla List
Subject:  Re: Two Toroid Test

to: Ed

Sounds like a great coil and you're having fun.  We use a small 150 CFM
blower on our series resistor (0.75 Ohm) to keep it from overheating at
higher power levels.  Some of the surplus 3450 to 3650 RPM blowers put out
a lot of air in a small area and are reasonably priced.


> From:  Esondrmn-at-aol-dot-com [SMTP:Esondrmn-at-aol-dot-com]
> Sent:  Monday, June 22, 1998 12:19 AM
> To:  tesla-at-pupman-dot-com
> Subject:  Two Toroid Test
> Well, we put some major run time on the coil tonight.  Finally, a night
> no thunderstorms.  The goal here was to try the two toroid test in an
> to cause the discharges to go up and away from the primary.  Based on
> that I had done with my small 3.0" coil, I learned it worked best with
> large toroid on the bottom and the smaller toroid on top - not what I had
> guessed.  So I set it up with the 40" toroid mounted on the secondary,
then a
> 14" tall x 20" dia. cylinder made from aluminum flashing, then the 33"
> on top of that.  Sure enough, all the sparks came off the lower toroid
> went straight down to the strike rail, primary coil and the cement.  So
> for the earlier testing.
> I had plenty of power to break out both toroids with sparks starting
about one
> half power.  The best tune was at turn 9.5 on the primary which is
> what I had calculated - based on the 75% figure of adding the two toroid
> capacitances together and multiplying by .75 as in the article in the
> TCBA News.  Then I reversed the two toroids with the larger toroid on top
> It works great.  Virtually all the sparks leave from the upper toroid and
> out and up.  I had no hits to the strike rail with this set up.
> I achieved a new record for this coil with discharges of 92" to a
> wire.  Not bad, about 3.5 times the winding length of the secondary.  It
was a
> great time.  I shot two rolls of film and maybe we can get some posted
when I
> get them back.
> The best performance was with two of the new 1.6 ohm 1000 watt resistors
> series for 3.2 ohms and in series with the inductive ballast variac.  I
> noticed after many minutes of run time, the new resistors were smoking
like a
> bar b que.  Let me see, 40 amps through 1.6 ohms should be about 2,500
watts -
> I guess they should smoke a little.
> Big sparks in Spokane, Ed Sonderman