Re: Tuning a spark gap TC

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Original poster: "Dr. Resonance by way of Terry Fritz <teslalist-at-qwest-dot-net>" <resonance-at-jvlnet-dot-com>


Yes, we usually set the gap at around .080 to .100 inches during this tuning
with a 12 kV NST.  If you are running a lower voltage then set the gap so it
fires smoothly (rapid fire) at 30% setting on your variac.  Keep your run
times short --- usually 5-10 sec. bursts.  A segmented sparkgap attached to
the sec. coil is also a great aid for locating max. tuning points.

After all tuning is finished, then open it up so it hits Erms x 1.4 (ie,
your peak potential).  With 12 kV neons we seldom go higher than 0.200
inches max.  Extremely wide gap settings with erratic firing will usually
damage a NST even with protective circuits.

The key idea is never push a lot of power into a circuit that is not in the
best tune possible.  If you do the reflected standing waves can be very
stressful on your cap or xmfr.  You want the sec. circuit to absorb as much
power and energy as possible without reflecting it back into the pri.
circuit.  Take your time and use caution --- don't try to do it all in one
night --- even if you are excited!!

Dr. Resonance

Resonance Research Corporation
E11870 Shadylane Rd.
Baraboo   WI   53913

 >          I have seen posts that recommend tuning a TC at about 30% max
 > power before turning it up all of the way to avoid damaging components
that
 > may be out of tune.  I agree with this methodology, but my question is,
 > should you adjust the spark gap spacing so that it will arc at the new
 > voltage?  For my 15 kV system that would be about 4500 volts.  Not
 > adjusting the spark gap would the capacitor ever charge up enough to short
 > out the spark gap.  If it didn't, the primary would resonate at 60 Hz
 > right?  I am probably missing something here, so I thought I would ask.
 >          If anyone has any best practices or tried and true methods of
 > tuning that they feel like mentioning as well as some pitfalls to avoid
 > that would be much appreciated.  Thanks everyone in advance for your help!