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Re: First light, and a poor performance

In a message dated 98-08-25 03:39:33 EDT, you write:

<<    Just fired up my new TC for the first time tonight, and
 > unfortunately the output fell somewhat short of what I was expecting,
 > I'd be very grateful if anyone could make a few suggestions about how to
 > improve it.
 >     The system specs are as follows.
 >     Power supply, 11 kV (rms) polepig with resistive ballast made of 4Kw
 > of heating elements filter consists of 2x20mH inductors and a 1.7nF
 > bypass cap. Main tank capacitor is 7.42nF and the primary coil is a 30
 > degree inverse conical with 12 turns of 1 mm wire 7 mm apart. The
 > primary is spaced 20 mm from the secondary and the bottom turn of each
 > coil line up. The gap is 6x0.5mm tungsten carbide static gaps.
 >     The secondary is 4" dia and wound to 16.5" with 0.56mm enameled
 > wire, there are around 660 turns giving an inductance of 11.4mH and a
 > capacitance of around 8pF.
 >
 >     The system was run at first with no top load, tuning was around turn
 > 6 and the maximum arc length to a grounded rod was 8", with a 4"
 > spherical top load then the arcs reached 11".  When the system was run
 > for any length of time, the nickel coating on the top load was etched
 > through, and when the plastic underneath was burnt then the arc length
 > decreased dramatically. Also it was found after a short while that the
 > acrylic support structure of the gap had melted.
 >
 >     I am planning tomorrow to build a much better gap that can take the
 > heat for longer and a finite element array toroid 14"x3". that should
 > bring the system to 1/4 wave operation, and, I hope increase the output
 > because from looking at other's coils, 11" from 4Kw seems very poor.
 > If anyone else has any other suggestions for improving the system, I'd
 > really like to hear them.
 >
 >
 >                                         Steve
 > >>
Steve,

With a pole pig power supply, I doubt that a static gap will quench at all.  I
think you need to build a rotary gap.  I tried a static gap with my 5kva pole
pig and it would not quench - even with lots of current limiting.

Ed Sonderman