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Re: NSTs and Cap Charging (tests)(was 2 questions......)

In a message dated 99-04-11 05:05:12 EDT, you write:

<< With the larger cap, with static gap or sync rotary, I saw below rated
> power being drawn by the NST, unless I turned up the input voltage
> to over 120 volts input.  But I have to try fiddling a little more with
> the sync phase to see if I can get it to draw more power at 120 volts
> input.
 
> John Freau
   >>

Malcolm, Terry, Gary, Bert, Richie, all,

I still didn't answer the above fully, but I rechecked some of my 
tests, and made some new findings.

Using the original resonant charging set up with the 12kV, 30ma NST,
and the .0077uF cap, I rephased the sync gap to a new position which
gave me 42" sparks at only 640 watts.  So this now equals the
performance I obtained with the LTRS (larger than resonant sized) cap.
This was the major finding.
Also, using this sync phase position, I had to turn up the input voltage
to 140 volts input, the same as I needed to use with the LTRS cap for
the same spark length and power input.  I also found that I was able to
narrow my safety gaps to 1/4" from the 7/16" setting they were at. 
This new phase position is near the point where the gaps refuse to fire,
so this too is similar to the set up with the LTRS cap.

Just to verify, I went back to the original phase position, which did
give 42" sparks at 120 volts into the variac, and drew 740 watts as
I had seen in the past tests.  The safety gaps were set wide in this
test, and I forgot to see how much I might be able to narrow them, if
at all. 

Next I went back to the .0118uF LTRS cap, and found that it never
drew more than 400 watts from the 360 watt rated NST at 120 volts
input.  Of course the power increased quickly as the input voltage
was increased over 120 volts.  I thought I might had seen some
sync phase positions the other day that drew more power at 120
volts, but if they did, the spark output was weak at about 24".  I 
should recheck still more phase positions, since I'm not 100 % sure
here about the power draw at 120 volts, but I know the spark was
never strong.

I also made the same kind of test using the .0147uF LTRS cap and
it never drew more than the NST rated 360 watts at 120 volts input,
again, power increased quickly as the input voltage was raised over
120 volts.  Again I'll have to recheck for other phase positions to
verify that no positions can draw more than 360 watts at 120 volts
input.  But again, i know the spark was never strong at 120 volts
input.

BTW, regarding some recent work I did while powering my coil with
potential transformers, I didn't have enough ballast range for the set
up, so I'll have to redo those tests.  I will also try the larger cap
values for the 42" spark tests

John Freau