Continued Problems (fwd)
From: Esondrmn [SMTP:Esondrmn-at-aol-dot-com]
Sent: Monday, May 11, 1998 5:08 PM
Subject: Re: Continued Problems (fwd)
In a message dated 98-05-09 01:08:41 EDT, you write:
What is your main spark gap set at? This would be the total of the rotary
gap and the static gap. My guess now would be that you have too much gap.
My suggestion would be to record all your parameters ( i.e. primary tap
point, gap distances, rotary speed , current settings (amperage), ) so you
can get back to where you started from . Then close down your main gaps to
the minimum safe distance. I am not sure if your rotary gap is adjustable,
but if it is, I am sure that there needs to be enough clearance for
mechanical vibration. I would probably bypass the static gap in order to
start at the minimum gap distance.
I would then begin tuning the coil as if it were a brand new coil . I would
find the best primary tap point. At this point you may need a ground point
only a few inches from the toroid to tell (not having worked with a pole
pig, I don't know what to expect at this level). Tune it for maximum power
throughput without changing the gap length. When max output is reached,
record the settings. The safety gap on your cap should not fire at all
during this tuning. Open the main gap a couple thousandths of an inch and
retune for max throughput. Record the settings. At no point should the total
distance of the main gap (rotary and static combined) exceed the distance of
the capacitor safety gap or the safety gap will fire.
By doing this you will get a good idea of how your coil operates at
different voltage levels (your main gap controls the voltage at which the
capacitor discharges). You should find a point on the way where the max
output is reached without firing the safety gap.
If the safety gap is firing at a very low voltage, the first thing I would
check is too much resistance (including impedence) between the main gap and
the cap. If it is not that, then I would consider puting some chokes on
either side of the cap (chokes designed for large current i.e. out of 3/8"
tubing) to stop the high voltage spike reaching your cap.
I hope this helps.
The clearance on the rotary gap (between moving contacts and the stationary
contacts) is probably .08 to .10 on each side. The static gap consists of
three .030 gaps in series. I now have the static gap out of the circuit and
the next firing will be with the rotary only.