Re: Solving the DC coil mystery

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

Original poster: "S & J Young by way of Terry Fritz <twftesla-at-qwest-dot-net>" <youngs-at-konnections-dot-net>

To Deano and all DC coil affectionados,
 
See the idea below Deano posted recently.  FABULOUS!

 
> Original poster: "David Dean by way of Terry Fritz
<<mailto:twftesla-at-qwest-dot-net>twftesla-at-qwest-dot-net>"
<<mailto:deano-at-corridor-dot-net>deano-at-corridor-dot-net>
> > 
> A couple of years ago, maybe three, I spent a summer working on some
> 
> fancy gap designs, some for MOT supplies. If I understand, You are using
> 
> a MOT supply with now a voltage Tripler with a gap that operates like a
> 
> SPDT switch. The gap first charges the tank cap from the DC power supply,
> 
> then discharges it through the  Pri. coil.  That is one of the designs I
> 
> mulled over. The design then evolved to have the storage cap be very large
> 
> in relation to the tank cap size, with pulse capability. (low ESR) The tank
> 
> cap then became in series with the primary coil, and the spark gap first
> 
> charged the tank cap through the primary creating one "bang", and
> discharging
> 
> the tank cap through the primary creating another "bang". I started to build
> 
> the thing, but then lucked into a pig, so I used one of the rotary disks for
> 
> my first SRSG, then the other for my second. So I don't know if it would
> work.
> 
Deano - I tried it - yes it works!  Boy, does it ever work!!  By rearranging my
SPDT RSG per your idea, I gained amazing improvements with my twin 4 inch TC! 
Namely:  
1) double the BPS for the same RPM - I can now safely do 1000 BPS (8 spinning
electrodes -at- 3750 RPM).
2) No power wasting, current limiting, "softening" tank charging resistor
needed - wonderful!!  I connected directly to my 6 MF reservoir cap and it
stayed cool as a cucumber.  With my other arrangement, it would get rather warm
without a big power resistor to limit current.  The primary seems to limit the
peak current very nicely.
3) More efficient:  old way took 1440 watts to produce a 42 inch arc (500
BPS).  Deano's way took 1344 watts to jump 48.5 inches (1000 BPS).   I was
chicken to see what it would do at 1440 watts.
 
THANK YOU Deano!  I recommend others give this a try.  Here is the schematic -
use courier new font 
 
 
+12KV -|--------------O       O--|
       |               ^         | 
       |      async RSG \        |
       |                 \       |    
 6 MF === reservoir cap   O      |
       |                  |      |
       |       tank cap  ===     |
       |        19 NF     |      |    
       |                  -at-      |
       |          primary -at-      |
       |                  -at-      |
       |                  -at-      |
-12KV -|------------------|------| 
 
Other experts have said the reservoir cap only needs to be about 10 to 20 times
larger than the tank cap, so mine is overkill.   It is actually 4 23 MF 4.1 KV
eneragy storage caps in series from USA Manufacturing at $2 each.  (They have
wonderful capacitor bargains.  MO caps 0.97 -at-2.2KV are currently selling for 70
cents.   3 MF -at- 1.5 KV for 75 cents.  <http://www.usamfg-dot-com>www.usamfg-dot-com)
 
Again, thanks Deano!
--Steve