Need help with mystery

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Original poster: "S & J Young by way of Terry Fritz <twftesla-at-qwest-dot-net>" <youngs-at-konnections-dot-net>

List,

This is more puzzlement regarding a problem I mentioned in earlier posts.  I
have a DC supply of about 12 KV which has a reservoir cap of about 6 mfd.
It connects to a RSG which alternately charges the tank cap from the DC
supply, then discharges it into the primary (SPDT switch action).

If I directly connect the output of the reservoir cap to the RSG, the
charging gap spark is quite bright and noisy (same as the discharging gap
spark), and tends to erode the electrodes.  The charging gap sparks can be
toned down by putting a power resistor between the reservoir cap and the
RSG.  This lets the tank cap charge a bit more slowly and doesn't burn up
the gap electrodes as much.  Charging gap spark is reduced to a much
smaller, dimmer spark, and TC performance is still good.

Here is the puzzle.  My most recent power resistor is 6 400 ohm 10 watt
power resistors in parallel for 67 ohms at 60 watts.  Current going the
resistors is high amperage pulses, but the average current is only 50
milliamps.  Current is measured with an ordinary moving coil ma meter.

Power dissapation for this series resistor is I-squared R = .05 x .05 x 67
which is about 0.17 watt.  So the resistors will stay cold, right?  Wrong!!
When the TC runs for a minute, the resistors get literally smoking hot!  I
am guessing the power dissapated is well over 100 watts!!  This means the
resistor impedance is at least 40K??

Another clue is that the voltage pulse across this power resistor is on the
order of 5 KV as it will jump across a 1/4 inch gap.  If the power resistor
is a pure resistor, this would indicate current pulses of about 75 amps
flowing into the 19 nF tank cap.

What in the world is going on here??  My guess is the wire wound power
resistors are also inductors - thus the higher impedance.  I suppose I need
to make a big bank of carbon resistors (non-inductive) to see if the same
heating effect occurs.   (another alternative of internal arcing between
turns of the power resistor doesn't solve the mystery.  This would not
generate any more heat than pure resistive heating).

So, list, why do my power resistors get smoking hot?

I suppose the same effect should happen with a normal AC powered TC.  How
about if some of you add a power resistor in series with your spark gap and
see what happens?  If you have a 60 ma NST, for example, the RMS current
through the resistor should be 60 ma or so.  If it was 100 ma through a 50
ohm power resistor, it should only dissapate a half a watt.  A big resistor
would barely get warm after a few minutes.  What do yours do?

Thanks for any light you can shed on this mystery.

--Steve