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60 BPS sync TC tests
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From: FutureT-at-aol-dot-com [SMTP:FutureT-at-aol-dot-com]
Sent: Wednesday, February 25, 1998 12:56 PM
To: tesla-at-pupman-dot-com
Subject: 60 BPS sync TC tests
Greetings all,
Prior tests showed good performance at low break rates (120 BPS
synchronous), such as 42" sparks at 640 watts, 46" at 700 watts,
64" sparks at 1560 watts, etc. Higher break rates did not seem to
help that much, so I figured it might be useful to try an even lower
break rate.
I modified my 1800 rpm sync gap by removing 2 of the spinning
electrodes (leaving 2 in place), and I doubled the size of my tank
capacitor. By removing the electrodes, the gap now fires only
on every other half cycle or 60 times per second. I'm using a
potential tranny, and adjusting an external inductive ballast for
best operation.
The performance was quite interesting and quite good. I'm now
obtaining 45" sparks at 600 watts, at 60 BPS. The sparks appear
dimmer, and less bolt-like than at a higher break-rate, but the sparks
have quite a wonderful way of slowly reaching out...and out, to reach
the measuring wire. The sound at 60 BPS is unique in itself.
I also did some tests at a little higher power, here's a chart of all the
results:
___________Watts 120 BPS 60 BPS
600 ----- 45"
small 640 42" ----
toroid 700 46" ----
____________800 ---- 49"
large 900 ---- 55"
__toroid_____1560 64" -----
Unfortunately I did the tests at different power levels which makes
it a little harder to interpret. In some cases the coil was most
"happy" at a certain power level, although I could probably obtain
results for comparison at identical power levels, and I may redo
the tests with that in mind.
It is also important to consider that these new low break-rate tests
had two strikes against them so to speak; 1) the gap I'm using does
not quench as well as the series quenching rotary used for the 120
BPS tests, 2) the primary is still #12 wire, but considering the
larger *bang* size, a thicker wire should be used. The 60 BPS
set-up outweighs these negatives to deliver impressive performance.
It is possible that a 60 BPS system could be driven by a level
shifted (voltage doubler) type power supply which would allow both
(positive and negative) cycles of the 60Hz AC to be utilized, and
permit the use of lower voltage transformers. In such a system,
the sync gap would have a 50 - 50 chance of starting up on the
correct AC half cycle, so this would have to be kept in mind. Also
RF kickback issues would need to be addressed.
It is possible that NST's would not fare well in this system due to
potential resonant voltage build-up conditions.
John Freau