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New testing, more


From: 	Esondrmn-at-aol-dot-com[SMTP:Esondrmn-at-aol-dot-com]
Sent: 	Thursday, September 11, 1997 7:10 AM
To: 	tesla-at-pupman-dot-com
Subject: 	New testing, more


Well, I fired up my coil again tonight after a few months of waiting for the
replacement Condenser products capacitor.  It arrived a few days ago and was
installed with a spark gap across it set at about 1.0".  I also recently
rebuilt my ground system using solid copper flashing to interconnect all the
ground rods and to the base of the secondary - only maybe 4.0 feet from the
base of the secondary to the ground system.

Using a 14.4 kv, 5kva pole pig and a 220 amp lincoln welder with superior
powerstat for primary power.  I have a switch system set up to switch in
resistor elements in parallel with the welder.  All switches off is 22 ohms
in parallel with the welder and all switches on is 3.3 ohms in parallel with
the welder.  I set the welder on low and the rotary on low speed.

When I first powered it up, the primary current in to the pole pig was about
12 amps.  The gaps would only fire erratically even at full variac voltage.
 I tried switching in more resistive load in parallel with the welder and the
gaps almost quit firing altogether with all elements on - about 3.3 ohms.  I
unplugged the resistive element bank so the welder was on it's own.  As I
increased the variac voltage, the gaps started firing erratically again and
the spark gap across the main (.025 mfd) cap started firing.  Someone said
this would be very loud and they are right, no mistaking if it is firing or
not.

I tried different tap settings on the primary and did not have much luck.
 Still can't get the gaps to fire smoothly.  The coil is trying to tell me
something and I just don't seem to get it.  I have been having problems with
this system for the last year, every since I rewired all the primary
interconnects by replacing the wire (two pieces of RG213 in parallel) with
3/8" copper tubing.  This coil used to run very well and has produced 80"
discharges.

I thought maybe the RG213 high voltage feed lines to the coil maybe shorting
internally but I should see high primary current draw if that is the case.  I
have checked all the primary wiring probably a dozen times and can't find a
problem.  I am ready to take all the copper tubing back out and rewire all
the primary interconnects with wire again.  I have three static gaps in
series with the rotary gap.  The coil originally ran fine with these in the
circuit and I thought it would help quenching - should I pull them out?  They
are set at .030" each.

After I shut the system down for the night, I checked the rotary gap
carefully and found the gap between the stainless steel acorn nuts on the
polycarb disc and the fixed (2) tungsten electrodes to be a bit wider than I
would like.  The disc doesn't run perfectly true so I need a bit more gap
than I would like.  The total was probably about .150 to .200".  I closed it
down as close as possible without it hitting.  The total gap now is probably
.100" plus the three .030 static gaps for maybe .190" total.  Will the system
be this sensitive to gap distance setting?

Anyone have any ideas?

Now I am answering my own post.  This exact set up has now killed two C.P.
caps.  I can't afford to keep doing this.  Maybe you can have the resistance
of the primary circuit too low and the cap can't take it.  By the way, the
primary is 14 turns of 3/8" copper tubing for a total of 84 microheneries.

Thanks,  Ed Sonderman