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Help in calculations



Hello Everyone
I have been working on shunt or neon transformer driven TCs with some 
moderate success. I have spent some time reviewing the archieves for the 
numerous references in the past and they have been quite enlightening, in 
particular Richard Quick's responses offer some real insights into 
various aspects. Nevertheless I have continued to pursue longer 
discharges using synchronous rotary gaps (srg) and now am now using a  
15kv, 120ma neon. I have found several advantages in using a srg. For one 
thing I can actually control the voltage across the primary capacitor by 
setting the firing point in the input sine wave. It also appears that  a 
maximum discharge can be achieved by adjusting the exact firing phase of 
the gap(s). Right now I am using a srg with one firing for each half of 
the input sine wave. It is not obvious to me that I am achieving maximum 
power transfer with only one firing per half cycle. It is certainly 
possibe to add gaps or contacts to add another firing   per each half 
cycle but would I gain anything. 

My question(s) to the group are for help in trying to determine the 
voltage across the primary capacitor at any time "t". My problem is how 
to handle the current limiting / impedance of the neon and how to fit 
this into the classical capacitor charging time constant.

For instance...If I set the first gap to fire when the voltage across the 
cap is at .707 of the peak, how long will it take the cap to recharge to 
.707 of the peak again? Will it even get there during the same half 
cycle? If I can know the time constants involved, it is obvious that the 
srg can be set up to fire at the right times. Also if I know the the 
maximum voltages to which I can get the cap charged, it becomes trivial 
to determine if additional fires per half cycle will gain any increase in 
power transfer.

Why do all this? Basically I believe that bigger discharges can be wrung 
out of neons and this may be one way of doing it.

My present system using the above mentioned components and a .021 cap 
delivers 54" point to point discharges. Since I have gone to the 
synchronous gaps I have not blown up any more neons or capacitors either.

I would appreciate any help that anyone in the group can offer.

Skip Greiner