Re: synchronous RSG or not

["Barton B. Anderson" <tesla123-at-pacbell-dot-net> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

Interesting observations. 

An SRSG at 120 bps can be phased to fire at each peak of the AC 1/2 cycle. One
can also run SRSG's at 240, 480, etc.. bps rates, but I doubt an SRSG gap rate
above 120 will show any improvement (probably a loss of spark length). You have
demonstrated what is "nice" about a DC drive spark gap. With DC, varying the
break rate is simple and odd things do occur at different rates of the break.
Although I run an SRSG currently, I have ran DC and I loved being able to
adjust the break rate while the system is running. My particular coil had
longest arc lengths at around 270 bps at that time (I didn't try extremely high
rpm though). 

I am curious however, what size capacitor are you using? 

Tesla list wrote: 
>
> Original poster: "D.Wightman" <dwightman-at-mmcable-dot-com> 
>
> Recently i ran my 8 inch coil at various speeds on my rsg. it has 6 rotating 
> electrodes and 2 fixed electrodes,the drive motor is d/c with a built in 
> tachometer..The coil is powered by a 14400 * 5kva pole pig..the rpms were
> from 
> 1000 to 5000 rpm...all of this is on video tape which is 30 minutes long..an 
> interesting phenomona happens..at fairly low power levels and slow rpms the 
> coil will function very well it was easy to get 5 foot ars, by turning up the
>
> rpm of the rsg at this point there is no visible improvement in performance..
>
> when you turn the power up to the coil it would tend to want to arc down the 
> secondary, and also hit the secondary..by increasing the rpms of the rsg at 
> this point it would seem to go back into tune and the destructive arcing
> would 
> stop..at this point you can really crank up the power to the pole pig and get
>
> nearly constant 8 and one half and 9 and one half foot sparks.. this
> secondary 
> coil is only 25 inches high!!!! now upon further experimentation...at full 
> power..rsg at 5000 rpm 10 foot sparks super hot, hitting a metal support beam
>
> for building we would begin to adjust the speed of the rsg..down at approx
> 2000 
> to 1000 rpm the destructive arcing would propagate..arc length was effected
> by 
> at least 10 to 15% "reduced arc length"..at 700 to 1000 rpm you would see
> white 
> hot spots on the secondary coils,by turning the rsg at that point immediatly 
> back to the 2500 to 3500 rpm range the hot spots went away and the unit was 
> really getting with the program. at that point the rsg was turned up to
> around 
> 5000rpm, it seemed that power output was slightly reduced maybe 5 %... 
> unfortunatly this experimentation has destroyed the secondary but the results
>
> are very interesting for those of you who would like a copy of the tape let
> me 
> know.. in the end, you will see it with lots of smoke pouring out of the 
> secondary and a small fire .....these things are GREAT...now for the question
>
> one must ask...why do most perfer synchronous rsg's?? what is the point.. it 
> did seem that a spark gap can be tuned for a specific power level....does 
> synchronous operation tend to mostly protect the caps or the
> transformer.....i 
> realize that the 60hz a/c cycle can be optimized, sort of,, by selecting a
> rpm 
> on a rsg that tends to "hit" at the peak of each cycle...but i really did not
>
> see this..thanks everyone.