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Test of 6" coil

Subject:  Test of 6" coil
  Date:   Tue, 27 May 1997 11:51:05 -0400 (EDT)
  From:   Esondrmn-at-aol-dot-com
    To:   tesla-at-pupman-dot-com


I finally got my 6" coil set up this weekend to try some new tests. 
Based on
tests with my small 3" coil, I used two toroids this time.  The 40"
mounted
on the coil, with a 14" tall x 20" wide hollow cylinder made from
aluminum
roof flashing for a spacer with the 33" toroid sitting on top of this. 
The
idea here is to get the discharges to go up and out and stay off the
strike
rail.  I also made up a new switch system for the resistive bank in
parallel
with the welder.  It is now variable from one 2000 watt element (about
22
ohms) to 3.3 ohms with all elements in the circuit.  There are 6 total
elements.  This is all an attempt to get the primary back in to
synergistic
tune which I lost last year when I rebuilt the primary set up and
replaced
all the interconnect wire with 3/8" copper tubing.

I had the rotary speed set down quite low for this first test.  As I
started
to bring the voltage up on the variac, the welder started growling, the
spark
gaps started to fire but weak and erratic - just like last time I tried
to
run it.  No spark breakout from the toroid.  I was in the process of
closing
the switches one at a time on the resistive element bank to see if this
would
make any difference when everything stopped.  The 30A fuse on the
powerstat
variac was blown.  I traced this problem to a short in the secondary.  I
further traced this problem to a shorted capacitor.  My trusty Simpson
VOM
measures about 10 ohms across the capacitor.  This is a Condenser
Products
cap .025 mfd rated at 20,000 volts AC.  This cap came from the second (I
think) group purchase.

At least this cap did not blow up like the last one.  I don't understand
how
I can possibly be doing anything to destroy these caps.  This is the
second
Condenser Products cap that I have lost.  Anybody have any ideas here? 
Am I
just having a bad run with C.P. caps???  I will call them today and see
if I
can send this unit back.

Looking at my notes from last July, I did get this capacitor to run good
in
the system one time.  I set a new distance record of 80" discharges at
that
time.  It ran for maybe 15 minutes and then the primary started acting
up -
just like it was this time before the cap finally shorted.  I am
guessing
that maybe I don't really have any primary set up or design problem and
the
only problem has been bad caps.

I know there has been a lot of debate about this, but who should I go to
next
time?  Plastic Capacitors?  Has anyone on this list had one of their
caps
fail?

Ed Sonderman