SGTC

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Frank <fxrays@xxxxxxxxxx>

An interesting question for the group:

Which circuit makes a better SGTC and why?

1) The cap in parallel with the HV transformer and the spark gap in 
series with the TC primary

OR

2) The spark gap in parallel with the HV transformer and the cap in 
series with the TC primary

OR

3) The SG in parallel with the HV transformer and caps in series with 
EACH side of the TC primary

I have plans dating back 100 yrs to the present and all 
configurations are used for small and large coils. There does not 
seem to be any preference and I have circuits using 20 KV 
transformers with all options above.

The gap in parallel configuration seems to be slightly more present 
in designs but not by a large margin.

The SG in parallel adds some over volt  protection to the HV xfmr but 
also the risk shorting the transformer is present if the gap is left 
closed for any amount of time.

The third option completely isolated the TC primary from the HV 
transformer making it by far the safest for shock hazards.

Thanks, Frank