Atomic Laboratories 71869 Tesla Coil

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Original poster: "Peter Birk" <birk@xxxxxxx>

Volunteered to work on a Tesla coil from the local high school.  The physics
teacher complained the spark was weak and he also got shocks when trying to
flip the switch on the metal case.  I was able to draw ~1/4 inch sparks off
the case.  The first thing I checked was the secondary.  I expected to find
the bottom end grounded.  Instead it leads to a potted lump of plastic that
is then connectd to the metal case.  Inside the plastic I can see a large
disk capacitor labelled .01M 3KV.  Across the capacitor are three resistors
in series red-red-green.  When I put an ohm meter between the bottom of the
secondary and ground it measures 25 X 10**5.  I was expecting to see more
like 66 X 10**5.  This suggests some problem with the disk capacitor.  I
just can't figure out the purpose of this arrangement.  I'm planning to
attach a piece of ground strap to the case so it can be grounded to a water
pipe.  I'm not sure what to do with the bottom of the secondary.

Pete from Virginia