Re: TC Electrostatics
Conclusion: The Tesla Coil is a major electrostatic device.
A series of experiments were preformed measuring TC base current as
measured with a Weston Thermo-galvanometer and various components in
series. The meter and all components were placed in series with the TC
base. Again, the square root of meter reading was not taken, even
though the meter measures I^2.
The variac was adjusted (~60 vac) for 90 ma meter reading. The spark
discharge appeared the same as with no meter in series. Forward
conducting, reverse conducting and back to back blocking diodes were
placed in series with the meter and TC. The spark discharge appeared
unchanged and meter currents were 80 - 90ma. The diodes were checked
with DC and appeared good afterwards.
A 22 uH ceramic roller inductor was place in series. The spark
discharge appeared the same as originally and meter currents were 90 -
95 ma. This coil was off axis to the TC secondary and did not appear
to affect tune or TC output.
A 50 pF 35 kV fixed vacuum capacitor was placed in series. Spark
output decreased markedly and meter current read 20 ma. This was off
axis capacitance for the TC secondary and did not participate in the TC
field. Attempts to retune the TC primary made little change in output
and base current.
The coil was fired without a secondary ground connection and Richard is
right that the TC seeks ground/counter poise with a vengence. The base
of secondary arced ~ 3" - 4" over a plexiglas barrier to the TC primary
coil. Of course, this is a straight shot to the neon secondary. I
stopped it immediately. Neon still fires, for now anyway.
Blocking EM base current with diodes has little affect on the coil
output. My next experiment is to confirm with a current shunt and
scope that EM is truely blocked with the diodes. If the diodes blocked
any EM and EM is the major electricity (really basic term) responsible
for TC output, then there should have been some indication of decreased
output. This doesn't appear to be the case. Note, as in measuring TC
output with the ESVM, it appears that diodes permit passage of
Adding series inductance made no real change. It is off axis and did
not appear to change tune, spark output or base current. Inductance
should imped EM current at RF frequencies and if EM is responsible for
TC output the output should have decreased. The output did not
decrease. The inductor should easily conduct DC and presumably
electrostatic charge. Since base current and coil output were
unchanged with increased inductance it is good evidence electrostatics
may be involved.
My first impression of decreased spark output and decreased base
current using the 35 pF capacitor in series was that the coil was out
of tune. Retuning didn't change much. It's noted that the capacitor
is off axis and does not participate in the TC field or function. It's
my impression that this added capacitance just gets lumped in series
with the earth capacitance. The cap presumably should conduct most of
the EM current, but block DC current and presumably electrostatic
current. Again, if EM current was primarily responsible for TC output,
the output should not have decreased so drastically.
These findings are qualitative and preliminary. Much work and
verification must be done. Correct tuning with and without added
capacitances and inductances must be verified.
It appears there are two basic currents in Tesla coils. The TC
secondary is coupled to the the primary driver and of necessity energy
is transferred primarily by electromagnetic induction. Resonating coil
energy and TC ouput appear largely electrostatic in nature with a
secondary EM component.