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Re: Primary Strikes

Tesla List wrote:
> 
> >From Esondrmn-at-aol-dot-comWed Jun 19 21:33:27 1996
> Date: Wed, 19 Jun 1996 16:16:20 -0400
> From: Esondrmn-at-aol-dot-com
> To: tesla-at-pupman-dot-com
> Subject: Primary Strikes
> 
> Richard Hull,
> 
> I saw a recent post of yours about directing discharges from a toroid.  I am
> having a problem with my 6" coil with strikes down into the primary.  I use a
> 40" toroid and am running between 5 and 9 kva.  Pushing it and probably
> overpowering this coil.
> 
> I have a strike rail around the top of the primary.  Previously, I have had
> to lay a coat hanger (or piece of wire) on the toroid, sticking out over the
> edge, in order to run the coil at all - at higher power levels.  Without the
> wire, the strikes would hit the primary in the first few seconds and fire the
> safety gaps which would stay fired until I removed the power.  A couple of
> months ago, I added a continuous ridge to the top outside edge of the toroid.
>  I used 3/8" plastic tubing, taped in place and covered with aluminum foil
> tape.  This had helped a great deal but I still cannot run more than maybe 10
> or 15 seconds before the primary gets hit and it all shuts down.
> 
> My toroid is mounted about 10" above the last turn on the secondary.  The
> resonant frequency is around 130 khz.  Do you have any ideas on how to
> prevent this?
> 
> Thanks,  Ed Sonderman

Ed,

The solution to no primary hits lay in getting rid of the primary!  This 
is no joke either.  Only a magnifier system will ever perform to 
"plus-ultra specs"  A two coil system is doomed to the primary slapping 
limitation.  I don't know the actual spearation between the base of the 
toroid and the primary winding.  It should be about 4-5 feet!  Nemesis, 
our best and biggest two coil system (10-13 KVA), had to have a full 
grounded ring around the primary of 5/8" copper pipe 1" above the outer 
primary turn.  It was hit all the time!  The primary, itself, was 
virtually never hit by the addition of this ring.

I am sorry about you primary hits, but there is a limit to the 
performance of two coil systems.  This limit is always related to the 
required proximity of the primary to the output terminal.

Richard Hull, TCBOR