New Coil/First Run (15 1/4" dia)

Subject:  New Coil/First Run
  Date:   Sun, 27 Apr 1997 07:23:56 -0500
  From:   Chuck Curran <ccurran-at-execpc-dot-com>
    To:   Tesla List <tesla-at-pupman-dot-com>

Hello All:
        Last night I was finally able to set up and put power to my
coil.  This is the one with the 15 1/4" dia. secondary with a 56" long
winding of #15 wire (motor magnet wire comes in 1/2 size steps and odd
numbers too).  The toroid is 10 1/2" x 56" and I attached a breakout
bump during assembly.  Well, things went O.K. at first.  I did video
tape it in order to slowly examine things later and that will help.  As
I ran up the autotransformer I was expecting to hear the spark gap and
then with a bit more input voltage achieve breakout on the toroid.  As
soon as I heard the gap fire within a split second 6-8 foot sparks shot
out of the breakout bump on the toroid.  There was also quite a bit of
light coming up from beneath the primary where I house the spark gap,
more than I recall from when I ran just the one .025 CP cap.  Oh, I
better mention I had my new Plastic Capacitiors .05 and the older .025
CP cap in parallel.  The light had me watching since it really reflected
off the bottom of the aluminum foil covered toroid.  Well, within about
20 seconds I apparently popped the fuse on the circuit for the rotary
motor and it started to wind down with an interesting display of how
higher break rates promote better spark! I did use a tach to set the
rotary at a break rate of 360 bps for this first run. Today I'll be
checking out the details of the short run and then try again.  I watched
the video, in some sections frame by frame and I didn't see any clear
evidence of any "unplanned" arcing.  The light coming up from the vacuum
and rotary gaps did however sort of mask things abit so it's really way
too soon to know if the coupling and other items are O.K. or not.  The
few sparks that did occur were dramatically more intense with this
bigger coil when compared to my 8" dia secondary coil from last year. 
The final resonant frequency turned out ot be 65 Khz on this new coil,
just for information.  I hope that within about one hour today I'll have
things ready for another test run, even though rain is predicted, I'll
at least get it ready for today or tomorrow!

Chuck Curran
Cedarburg, WI