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A TC without sparks ???


Greetings fellow TC'ers,

I have a serious question for the more experienced ones among us,
which I am fairly sure will have been asked by someone here before.

        I WANT TO HAVE MY TC MAKE NO SPARKS !

I have decided to build a synchronous rotary gap for my 2kW TC,  in an
attempt to achieve three things:

        1. Increased performance over RQ-gap,
        2. Smoother running of the TC,
        3. Hopefully less radiated interference.

I have taken real measurements from my ballasted supply,  done some
simulations and decided on a 200BPS sync' gap.  (Would be 240BPS in
the states.)  This should give me 2 bangs per half cycle of the supply.

I am equipped with an oscilloscope,  HV probes etc,  and would like to
monitor the capacitor voltage in between adjustments at the setting-up
stage,  __BUT__  I don't want sparks flying off my secondary while I
am making measurements !

I know that if I physically remove the secondary and toroid assembly,
then there will be no sparks, but I have been told that this will
eventually damage some components since there is no destination for
the primary tank energy.  As far as I can tell, I need to provide
a loss in the primary circuit so there is somewhere for the power to
be dissipated.  I have many high power resistors, quartz
security lamps... etc which were available as loads for ballasting etc.

MY QUESTION IS THIS:

Can I run my coil with the secondary removed, if I either:-

1. Fit a suitable resistance in parallel with my primary winding to
   absorb the RF energy ?

2. Replace the primary winding with a suitable resistance ?

3. Insert a suitable resistance in series with the primary winding ?

Remember at this stage all I am interested in is the primary cap
charging characteristic.  I know other people have done something like
this before.

Terry - Didn't you do some testing of spark gaps with the secondary
        absent ?

Finally,  can anyone suggest what sort of change in performance I should
see going from a forced air cooled RQ-gap to a 200BPS sync' rotary on
a 2KW 4" coil with Cp=44nF.

                                Richie,

                                - Trying not to make sparks (for now)
                                  in sunny Newcastle.