Re: New idea for TC Primary

From: 	Peter Electric[SMTP:elekessy-at-macquarie.matra-dot-com.au]
Reply To: 	elekessy-at-macquarie.matra-dot-com.au
Sent: 	Monday, July 14, 1997 3:38 AM
To: 	Tesla List
Subject: 	New idea for TC Primary

Glad to see the list is back up, many thanks Chip and Storey for your

After the recent discussions on the 30vs 60mA neons, It seems to me that
an AC Tesla's primary circuit is basically a no win situation with
regards to power efficiency. You have to provide inductive balasting, or
current limited Xformers to be able to quench the gap after the gap
fires but then you are limited by this inductance as to how fast you can
re-charge your cap and this in turn limits your maximum breaks/sec. Also
as the AC cycle reverses, whatever charge the cap already has is wasted,
as it must discharge before it can start to charge with the opposite
polarity for the next few breaks.

With this in mind, I propose the following system. A pole pig or even
Microwave oven transformers and voltage doublers, are used to produce
around 10Kv DC. (in this mode of operation, they should be reasonably
efficient). This is used to charge some fairly beefy caps, say around
1uF. The output of this supply is connected to a standard TC primary
circuit but via a special, two stage rotary gap as follows

      Commutator    Discharge
         Gap         Gap
----------* *--------* *---------
+                  |             \
                   |             /
High current      --- Pulse      \ TC
DC Supply         --- Cap        / Primary
                   |             \
                   |             /

The Gaps consist of a motorized plexiglass disk with a Cylinder of brass
with four notches on the inside, say 4" diam (commutator gap) and a ring
of bolts on the outside lined up with the notches, say 6" diameter
(normal gap). The gaps are arranged so that when the normal gap on the
outside lines up with its discharge terminals, the comutator gap breaks
the flow of current due to the notch. The commutator gap must be set up
with fairly fine tolerances.

The basic idea is to allow the pulse cap to charge up via the commutator
and then discharge via the normal gap. The commutator will allow the cap
to charge very rapidly, as there is no inductive limiting from the
supply filter caps, and then the normal gap will allow the cap to
discharge and quench rapidly as, at that moment, the supply is
disconnected. Theoretically, the number of breaks per second should only
be limited by the DC supply current and the size of the primary cap. The
primary cap could be kept fairly small and the system run at very high

Has anyone heard of, or tried this idea? The gap should be fairly easy
to build for you guys that have lathes, unfortunately I am not in this
category yet. Please send me flames or otherwise as I intend to try the
idea as soon as I collect enough parts.


Peter E.