Re: Superior Power Supply

["Kevin Ottalini" <ottalini-at-xxxxxxxxxxxxxx> (by way of Terry Fritz <twftesla-at-xxxxxxxxxx>)]

Alan / Brian / All:
	My DC driven TC runs very well down to a BPS or so
and all the way up to 700+BPS.

There are certainly many interesting variations in the
spark behavior at different rates, as well as a few slightly
better spots where the AC ripple on top of the DC matches up
well with the ASRG rate.  Spark performance at the slower
rates though is very dependent on total losses and coupling
through the system since there is minimal reinforcement.

As long as the coil is resonant, (and reasonably efficient),
each shot will generate pretty much an optimum spark, and
the total input power will be self limiting.  I was running
a small (marginally tuned) 6" coil this Halloween that was
producing nice bright 18" sparks from around 1/2bps to
around 20 BPS from a 12/30 NST and a full wave rectifier.
The spark appearance was the same, just more of them at the
higher BPS (and more noise!).

One "problem" with slow rep rates is that the more powerful
the DC supply is, the faster the cap bank will recharge
until the gap dwell time is too slow to quench a single
discharge (it will start acting like a static gap).

For really slow spark generation, you need a large rotor
with only one or two poles so the dwell time is small.

My friend Mike Loftus suggested making a "steely shooter"
spark gap, where the main gap was fixed and a small tube
with air pressure would spit a ball through the center of
the fixed gaps and another tube on the other side would
receive the ball and dump it back into the feeder.

This might work very well for slow BPS DC driven coils
(and kinda cool besides!).

Kevin

----------
> From: Tesla list <tesla-at-pupman-dot-com>
> To: tesla-at-pupman-dot-com
> Subject: RE: Superior Power Supply
> Date: Wednesday, November 15, 2000 3:34 PM
> 
> Original poster: "Basura, Brian" <brian.basura-at-unistudios-dot-com> 
> 
> Alan,
> 
> I have to disagree. When I had my coil set up to run in a DC mode I was
> able to let the RSG spin down to less than .5-bang per second and the
spark
> length wasn't effected I was still getting 5'-6' arcs). What was
noticeable
> was the thickness and brightness of the arcs decreased as the bang rate
> dropped below 4-5 bangs per second.
> 
> Maybe Kevin O. has some comments on this. His DC coil ran at any break
rate
> if I remember correctly...
> 
> Regards,
> Brian B.
>