Re: what is an rf ground?

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

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

Tesla list wrote:

> Original poster: "marko by way of Terry Fritz <twftesla-at-uswest-dot-net>"
<moyson-at-tig-dot-com.au>
 
> Hello!
 
> i am just confused as to what an RF ground is.

	A question with multiple possible answers.
	(Skipping, for the moment, whether grounds 'help' performance,
	or are necessary.  I feel they are, and probably more so
	at high powers.  Others find differently....)

> Is it the same as a normal tesla coil ground?

	Since a Tesla system operates on RF (albeit LF RF) by
	definition a tesla ground system is an RF ground.  The
	discussion centers around a _good_ RF ground, which may well
	differ from 'any old ground'.

>as simple as a steak in the ground?
		^^^^^  8)>>  (sorry.  couldn't resist...)
	A stake WILL work, for Tesla work, since the frequencies
	are low (by RF standards...).  More stakes, or a buried grid,
	or some number of wide conductors will work better.  How
	useful a ground is seems to vary with the installation/system/
	design.

> or does an RF ground have special components??

	It should be:
		short
		Low DC resistance.  (more or less a given).
		'wide area (grid, several radials, wide strips
		(as flashing, etc...)

	A simple stake in the ground will work in 'good grounding'
	(damp) soils.  In sandy, dry, stony (ledge under) soils,
	something more elaborate may help.
	
	The idea is to get as much distributed area as possible.
	Minimal is 3-4 radials, better is more/more is better.
	(but test first with 2-3...)  Or two-4-as manyasonelikes
	stakes, separated as convenient...

> What about tuning?

	A Real Ground is not tuned, in my experience, as such, but:
 
> is it possible to "tune" a grounding??

	There are techniques which use tuned techniques to simulate
	a ground.  If a good (short, wide area) ground is available,
	likely a tuned ground will not assist.
 
> My understanding is that an RF ground is tuned.

	My understanding is as above.  That Said, if a good (RF) ground
	is available, and proves useful, monitoring the current flowing
	to it provides diagnostic and research info...

===============
An important aspect of most RF grounding installations is to separate
the RF base current from the 'house' or 'ac line' ground.  IF the
RF current gets loose in THAT ground (those grounds) it can do
unfortunate things to equipment and people.  By providing a separate,
dedicated, 'rf' ground, even as simple as a stake in the ground, the
RF current will, in general go _there_ and be less likely to wander
around the ac line ground, causing problems.