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of 1/4 waves and olde movies

>I've found again, if enough input power is used, the BEST amount of terminal
>capacitance is  the amount that would cause ACTUAL 1/4 wave resonance in the
>secondary  winding, I.E. a coil wound with 1800 feet of wire may resonant at
>around  230 to 250 Khz.with no terminal on top, but the WIRE in the secondary 
>is a physical 1/4 wave at about 130 Khz.

	hmmmm.  This is wot i was rambling about a while back" 1/2 wave of wire,
	wound, resonates as a 1/4 wave.  (ROUGHLY)  Depending on Form Factor
	(aspect ratio...).

+++++++++++++++++
Was it here or elsewhere, someone was aking about olde movie props and if they
had real purpose.  Some do, most don't.  Interestingly (to me....  8)>>), the
Jacobs Ladder effect is from real application, called arcing horns.  When a
HV switch opens live, it can arc.  By providing arcing horns (Upstanding \/)
the arc rises of its own accord, eventually blowing out AND removing the arc
damage from the switching contacts proper.  The "ring of fire" effect is simply
a form of rotary gap.  Various glowing tubes are usually of no practical
purpose.  Lines of sparking gadgets are usually high power contactor, clattering
in sequence, into a large, usually inductive load (good spark...8)>>).  Other
than these, my meory fades.  (Tesla coils, per se, for lightning are common...)

Had an interesting observation recetnly, in NH, where the trains to NYC run off
12KVAC/60Hz overhead.  One of the MU cars had a faulty pantograph control.  The
pan (the bit that contacts the overhead wire) kept dropping, then rerising,
then dropping.  Sometimes ther was a small spark.  Sometimes a nice lacy
12" (more or less) sustained discharge.  Pretty, after dark, but tough on the
pan and wire.  Presumably the variation was due to whether or no the compressor
was drawing power and where in the sine wave the break took place....

regards
	dwp