RE: Coil behavior

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Brian" <brianv@xxxxxxxx>

Something I have noticed, and I am by no means an expert on Tesla coils, is
that the top load depending on how it is made can change things
dramatically. I used some aluminum tape bought from a local store, and could
not get any break out, the load was 4 inch with an overall diameter of 20"
flexible aluminum. I made another one with an over all diameter of 16" and
began to get some break out. What I had noticed was the tape actually had a
very thin plastic layer which changing my capacitance and detuning the coil,
I bought some real tape and the TC performed as it should. I don't know if
this has anything to do with your situation, but thought I would let you
know so may check that.

-----Original Message-----
From: Tesla list [mailto:tesla@xxxxxxxxxx]
Sent: Saturday, October 21, 2006 11:12 PM
To: tesla@xxxxxxxxxx
Subject: Coil behavior

Original poster: "Glen McGowan" <glen.mcgowan@xxxxxxxxx>

Hello All,

I'm afraid to ask but I think I may be lacking in primary turns. I'm
running a resonate coil (poor planning on my part). That said I'm
running very conservitave spark gap settings. One of the issues I'm
running into is I have my tap connected to the very end of my primary
(15 turns counting the tap lead). I dont' get streamers at any other
position but the one I just mentioned. If I connect to turn number 14
I get nothing. I do notice however that my safety gap (Terry's
Filter) fires solidly at turn 14 and any other turn for that matter
and no streamers. The safety gap fires quit frequently even at
primary turn 15 but more pronounced at 14. ( I just realized
I  should prolly open up the safety gap a hair while proof reading my
post.).

My question is can I adjust anything besides adding extra turns to
the primary? Can I use a smaller toroid, raise/lower the secondary or
raise/lower the topload? I really don't want to re-build the
primary.  JavaTC says I should be tuning at 13'ish turns. I tried 13
and get nothing but a safety gap arc. I know I'm doing something wrong.


Transformer: 15/60
Primary: 15 turns of 1/4 copper tubing.  (including Tap lead.)
Secondary : 4" and 23" of actual coil on a 25" form. (first turn
level with primary, maybe a hair above)
Toroid: 4x19 sitting at 25" high.
MMC:  .0093uF  (Ya I know I'll build another one)