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Speculation: litz wire, sewer ground


Myself, i would not get litz wire, fearing that the small strands would be
subject to corona losses.  Much rather have solid wire of equivalent copper,
following the "use decent size seconday wire rule".  Litz wire should, due to
the "internal" insulation, always have lower "linear packing density" (which i
understand to bea good thing...) than plain insulated solid wire.  Litz wire
was developed for flexibility (irrelavant to tesla coil work) and hf perfromance
(relavant, but I do not believe Litz wire is apropos for hi power hf work.)

(For those unfamiliar with litz wire:
it is a specialized form of stranded wire, with the individual conductors
"insulated" from erach other.  The insulation is imperfect, by design, as it is
intended for separating the conductors to improve hf performance, not insulating
for large voltages (poor explanation.)  I believe sometimes the individual
strands are in fact "ribbons", meaning edges, meaming ease of corona...)

That said, the final (and interesting) test, would be to try it an _know_.

Sewer pipe grounds:

(this is a radio (ham) story.  Allegedly true.  Possibly relavant)
The ham, at his seaside cottage, had trouple getting a decent ground.  Sandy
soil, above the water level meant poor conductivity.  Finally got real good
results with grounded vertical, with base set in vent pipe from septic system,
and shunt feed.  Minor retune as the tide went in and out, but otherwise, ok.

Until....

As it happened, his mother in law was visting.
As it happened she was "in the john".

	Turns out the "facilty" was 1/4 wave from the base of the antenna.
	Along the nice, conducting, drain pipe.

	Can you say:
		Voltage Peak at the end of a 1/4 wave?
	?

In the case of Tesla Coil ops, the freqs are likely to be low enuf that the
1/4 wave point will be far enuf away that the power loss in the underworlds
will limit the voltage at the far end....

============
Oh.  Spark Gap tuning aid.  At a ham radio flea market, i once picked up a cute
little HV "voltmeter" intended for servicing TV HV systems.  Plastic tube, with
1 cm roughly sphere gap inside, mounted on threaded rods, adjustable spacing,
outside of tube scaled directly in volts.  Designed to fit in a shirt pocket
like a pen.  Similar widgy might be useful in coil work...

regards
dwp