RE: The Tabletop Tesla Coil Showdown - OFFICIAL RULES and WEBSITE

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

Original poster: "Lau, Gary by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Gary.Lau-at-hp-dot-com>

Hi Kevin:

I didn't think that the proposed restrictions were that severe as to make
the competition boring. I was only restricting the NST power supply and gap
so as to not over-volt the NST.  I'm not sure why you suggested using
identical secondary forms and wire, this is something that doesn't affect
the underlying fairness intent, and may have some surprising results.  The
optimum aspect ratio and number of turns have never been nailed down beyond
vague rules of thumb, and I would personally love to see people experiment
here.

I was hoping that differences in primary capacitance, top load size,
secondary dimensions and wire size, and gap geometry would give rise to
performance gains more so than assembly and tuning, which are pretty much
cut and dried.

I think it's vital to limit the power to a particular VA number.  While 5
Watt battery powered coils may indeed be interesting, it's pointless to
discuss them in the same breath with the class of coils I'm talking about.
Don't mix stock cars and bicycles.  I'll leave it to someone else to
organize a low power competition, it's hard enough to get a consensus for
the rules for the mini coil competition.

I think spark length has to be the only judging criteria.  Who among us is
qualified to render an _undisputed_ verdict as to which entry is most
aesthetically pleasing, based upon the photographic skills of the coil's
creator?  Don't forget, this is an on-line competition, there will be no
judge physically present to witness each coil.  Least expensive?  I'm
personally not interested.  Lowest power?  Can you say "off"?  Most
efficient?  If you supply the necessary instrumentation to all entrants to
measure time-averaged true RMS Watts, maybe, but since efficiency is not
linear /wrt power level, it will have to be at one chosen power level.

This is one competition (OK, with two, maybe three sub classes).  Look at a
car race.  All entries are pretty much the same.  I don't want this to be
quite so boring, but I don't want to mix stock cars, funny cars, and
unicycles, all in the same competition.  I think the things that make one
coil superior will be applicable to any power level, so it's pointless to
gather data on more than one power level class.

Again, my goal is to compare coils similar only in their power supply
sizes.  The proposed restrictions are to ensure that the power supplies are
equal power-wise and are not operated in a way that risks damage to the NST
while providing a performance advantage.  That would be too expensive,  too
easy, and does nothing to advance the art.

Regards, Gary Lau
MA, USA


>Original poster: "Kevin Ottalini by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <ottalini-at-mindspring-dot-com>
>
>The way the existing rules are stated this is not a particularily
>interesting contest unless you set up a small kit with all the parts in it
>like a stock car race.
>
>IE: identical secondary form, identical secondary wire, identical NST, but,
>leave the primary and the tank and the gap and the secondary topload to the
>imagination of the builder.
>
>That way the assembly, mounting, control and tuning all become the key and
>good challenge and all those that have problems can quickly implement the
>winning solutions and try it out for themselves.  Everyone wins then with a
>working table-top coil.
>
>If you want this contest to be real interesting, only limit the maximum
>continuous input power say ~ 80 watts (but don't reject battery-power coils
>with only 5watts or 10 watts!) and who knows what wonderful designs will be
>presented?  Remember inspiration is the basis for a contest, many who would
>never bother to build a small coil will do so if they have a bit of a
>challenge.
>
>Have a couple of winning categories if you want (DC powered, AC powered) and
>perhaps limit the maximum overall physical size (it is supposed to be
>table-top, and what does that really mean physically).
>
>And is the actual final winning category only spark length? or asthetic
>design? most creative? lowest power, highest efficiency, least expensive,
>etc etc all the things that really interest the people on this list who love
>to make sparks!
>
>As a benchmark, compare the contest design to say the Science-First (same as
>Edmunds) coil which is a pretty poor performer, but fits the bill physically
>and power wise.  It uses an inductive contactor running at 110v with a
>single-loop primary ... no NST and certainly not 80 watts but it is a
>table-top and it does work.
>
>That coil would be excluded under your existing contest rules (and I'm NOT
>saying allow the Science-First coil to be entered as a design unless it is
>substantially improved either!).
>
>Even Terry's GMHEI coil the way it's designed fits the description of a
>table-top tesla-coil design.
>
>Kevin