Re: Halloween Coiling and the FCC

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "davep by way of Terry Fritz <twftesla-at-qwest-dot-net>" <davep-at-quik-dot-com>

>>The RF ground lead is the most likely source of excess radiation.
>>For some reason folk believe that hammering in loads of huge
>>earth stakes will automatically ensure a good ground for the coil,
>>but if the ground lead has to travel from the coil base down three
>>flights of stairs, through the garage and out to the yard, that
>>doesn't really do anything for the coil, except to give it a
>>reasonably good antenna.

>>I would always advocate confining the E-field close to the coil,
>>by using an artificial ground plane beneath the coil, if it can't
>>be operated directly over the earth.
 
> I heartily agree.... keep the RF path short (that includes the path from
> topload to bottom of coil via ground...
	Concur, tho a good ground doesn't hurt.

	In a real sense, the phrase 'ground wire'
	is meaningless in RF work.  It is sort of OK
	at Coiling freqs, but gets meaningless as the freqs
	go up.  Once the wire is 1/10 wave, and up, its
	not a wire: its an 'insulator' (or, rather,
	varies with the frequency).  And makes a dandy
	Antenna, the while.  Using shielded wire is helpful,
	sometimes, if the source is shielded, filtered, etc.


>>To pick up a TC at 20 miles is really some feat!  At TC
>>frequencies, the background RF noise against which the TC signal
>>is received is quite high, so a fair bit of signal must be being
>>radiated - rather more than we would expect from the coil and
>>topload alone.
	Subject to correction:

	My impression is that HAMs used to work Spacelab with
	1W ish Walkie talkies?
	
	(hmmmmmmmm
	Work with NASA on a getaway special to receive from
	a Tesla coil while in space????
	(JUST KIDDING)
	)

-- 
	best
	dwp

...the net of a million lies...
	Vernor Vinge
There are Many Web Sites which Say Many Things.
	-me