Finishing First Coil

From:  djQuecke [SMTP:djQuecke-at-worldnet.att-dot-net]
Sent:  Tuesday, June 02, 1998 6:58 AM
To:  Tesla List
Subject:  Finishing First Coil

The closer I get to finishing the longer it takes <g>.

A couple of Q's:

1.  How closely must the chokes match?  I've built two, one is 3.81mH and
the other is 2.38mH.  Is 2.38mH enough with a one or two NSTs (15kV,
30-60ma) so that I can simply derate the larger choke?

Chokes are 22g on huge Flyback ferrites (mismatched ferrites resulted in the
differing values).

2.  I need to verify grounding data.  Just what gets hooked to signal ground
and what needs a separate ground.

    a.  NST has two input leads, two output leads.  I currently have built
the safety gap as two gaps between NST out leads and NST case.  Schematics
I've viewed indicate case should be connected to signal ground?

    b.  What about NST input ground lead?  (Actually I guess the question
is: Should the ground lead on the NST input line be connected to the case (I
don't think so), to signal ground (I don't think so), a separate ground
(seems plausible) or don't connect it at all (seems strange to me but...).

    c.  What ground should strike rail connect to?

3.  I see ton's of pix with coils running in garages.  I can't imagine
firing mine off in the garage (or in a kitchen as I've also seen).  I have a
rather crowded bench with electronic gear etc, flammables (paint, etc) and
other misc.  How far does the coil need to be from such gear? From a parked

Should just be a matter of a day or two now (but I've been saying that for a
week <g>).