Re: argh -- poor output on TC #2

To: tesla-at-pupman-dot-com
Subject: Re: argh -- poor output on TC #2
From: "Dr. Resonance" <Dr.Resonance-at-next-wave-dot-net> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)
Date: Mon, 13 Dec 1999 17:53:29 -0700
Approved: twftesla-at-uswest-dot-net
Delivered-To: fixup-tesla-at-pupman-dot-com-at-fixme

to: Stan

Don't use aluminum.  It's not a great conductor at RF frequencies and
diminishes the peak RF currents.  The peak RF currents produce the powerful
magnetic field linking the pri to sec coils.  If you start to diminish the
pri RF current peaks you will lose a lot of power that is available for
transfer.  Use copper or brass as a heatsink holder and then use only
tungsten electrodes in a reasonably large dia for the power levels you are
running.  You should be running a 3/16 or 1/4 inch dia electrode size with
this much power.  1/8th will work but will cost you some current in the
poorer quenching factor due to overheating of this small electrode cross
sectional area.

Regards,

Dr. Resonance


-----Original Message-----
From: Tesla List <tesla-at-pupman-dot-com>
To: tesla-at-pupman-dot-com <tesla-at-pupman-dot-com>
Date: Monday, December 13, 1999 9:06 AM
Subject: argh -- poor output on TC #2


>Original Poster: Stan <sdarling-at-columbus.rr-dot-com>
>
>Hello all, I have finished my TC #2.  This one is 30.5 in of 22AWG wound
>on 6" drain pipe.  Toroid is 6"x20".  Right now I'm using 3 15/60s and
>an EMMC at 22.5 nF.  Primary is .25" cu tubing spaced .25".  Using the
>original Victoreen ceramic gaps from my old coil, I get 45"+ which
>rapidly diminishes because (I'm assuming) of too much power and
>overheating for those gaps.  So, I put together a 'blast gap'.  I used
>some L-shaped pieces of aluminum and ran stainless bolts through.  I
>epoxied an appropriate PVC reducer about .25" from the gap and plugged
>my shopvac hose in.  In short, the gap was horrible--I'd say 20" of weak
>streamer.
>
>So my questions are:
>
>1) Anyone else used the Victoreen gaps at medium power levels?  How good
>are they compared to other possibilities?  Why was my blast gap giving
>such poor results or is it really that lousy of a gap?
>
>2) How much would a SRSG help output? 45" seems poor given the amount of
>power I'm dumping in.  What else would those with experience with
>various gaps recommend?
>
>3) I know for my 3 15/60's I should be using aroun 30nF to be mains
>resonant.  Would I be better off removing one of the NST's to get close
>to mains resonant with 22.5 nF?
>
>4) Would it be unusual for a coil like mine to have a large tuning
>range?  It seems quite content from about 9.5 turns up to 11.  My old
>coil had maybe a 1/2 turn range where output seemed to peak.
>
>I have noticed that this coil also seems much less drawn to typical
>strike objects.  For example, it seems happy to have its streamers go an
>extra 6" to hit wooden shelving than to hit a grounded wire with a
>pointy tip.
>
>Am I missing something?  I know I'll probably never match the efficiency
>of aces like Terry but this is pretty bad!
>
>Help! :)
>
>-Stan
>
>
>