Re: multigap

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Finn Hammer by way of Terry Fritz <twftesla-at-uswest-dot-net>" <f-hammer-at-post5.tele.dk>

Duncan, Chuck, all!

I have here a plastics catalog, and one entry describes a product called
"Flourosint". This is a trade name, but it is a Mica/Teflon composite,
which combines the excellent insulating, and heat enduring properties of
both, while avoiding the coldflow of teflon alone. Available as thick
walled pipe, ideal for parting off in the lathe, as washers for a gap of
this type. This is probably what I will use for my quencher, when/if I
get that far.

As far as sections go, I wonder:  The first spark gap that I made, was a
linear static, where I could suck trough the gaps. It had some 30 odd
sections max. It was my impression that the gap ran best, when each
individual gap was set to 0.35mm (14 thou) or less.

Now I am thinking, perhaps each gap should be set close to, or narrower
than  the distance that is equivalent to the minimum breakdown voltage
of air, or whatever atmosphere the gap is running in. Without alcohol or
external hydrogen added, this would soon be a Nitrogen atmosphere.

This gap didn`t last long, due to poor choise in materials, but it made
the running of the coil a pleasure, very smooth, in that there was
rarely any kickback into the safety gap.

Cheers, Finn Hammer

Tesla list wrote:
> 
> Original poster: "Dr. Duncan Cadd by way of Terry Fritz
<twftesla-at-uswest-dot-net>" <dunckx-at-freeuk-dot-com>
> 
> Hi Chuck!
> 
> Looks like you've got into this game with a lot less bother than I
> had.  If you want a chuckle at the hard way of doing things you can
> see it at:
> 
> http://home.freeuk-dot-net/dunckx/wireless/quenched/quenched_gap.html
> 
> There will be more photos shortly, possibly this weekend (I picked
> them up from the chemist today :-)
> 
> The only thing which does, well, not exactly worry me (OK it worries
> me) is that with the tubes at right angles, the actual 'contact'
> surface area where the sparks strike is going to be very small.  In
> practice you may find this makes absolutely no difference whatsoever,
> but I just wonder whether intense local oxidation will cause muck
> build up so rapidly that they tend to short.  Time and experience will
> no doubt tell.
> 
> Regarding performance, yes, multiple gaps are nice!  I have ten for
> 10kV (actually they're a little long and only eight are usually in use
> without the spark-stretching choke) and if it was not so much work and
> expense would have loved to have doubled that number.  Maybe one day
> when I'm feeling both rich and masochistic . . .
> 
> Dunckx