From:  Mark Finnis [SMTP:mefinnis-at-medicine.adelaide.edu.au]
Sent:  Wednesday, June 17, 1998 6:35 AM
To:  Tesla List
Cc:  Bert Hickman
Subject:  Earthing


Bert Hickman wrote, helping a first-time coiler .......

>The base of the resonator, center electrode of the safety gap,
>strikerail, and the case of the NST's should all be tied to a good RF
>ground which is separate from the AC Mains ground.

Now, I am also a first time coiler and I prefer to learn from others
mistakes of the past, rather than simply repeat them myself ........ OK
call me lacking in adventure ;-)

I ask this precise question by private e-mail to Malcolm in NZ, and he
suggested I earth as follows:

	NST-Case/earth + safety-gap	--->   mains earth.

	Secondary base			--->   dedicated RF earth.

Noting, that we have RC filter between tank and safety gap for my proposed
scenario.  (2 x 1K -at- 100W resistors & 330 pF 45 kV caps)

Mmmmmm ......  the more I read, the more confused I get   :-(

Another point of some divergence in opinion is the arrangement of main-gap
and cap in the tank for an NST (actually using a pair of 15 kV -at- 60 mA).

Most appear to say:

	M-G in parallel with NST output, then cap in series with primary.

However, I've also received conflicting advice on this one.

Hopefully my caps are arriving within the next week, so I'd like to get
these two "little" points clear in my mind before I "hit the third switch"

PS:  Yes, I was dumb enough to buy new & not cheap NST's (hadn't done much
research then !!!) .........

	..... SO I DON'T WANT TO FRY THEM   :-)



Mark Finnis			Hm:  61 8 82895205
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