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Re: Coil behavior
Original poster: "Gerry Reynolds" <gerryreynolds@xxxxxxxxxxxxx>
You have several choices (assuming the problem is really the fp>fs):
1. Lower the freq of the primary by increasing the Cp.
2. Add some offaxis inductance in series with the primary.
3. Increase the freq of the secondary by decreasing the topload capacitance.
4. Sometimes raising and lowering the topload can make small changes
in resonance as well.
Original poster: "Glen McGowan" <glen.mcgowan@xxxxxxxxx>
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.
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)