RE: First light...Sort of

Hi Aric:

I think you did a good job of self-diagnosis.  By all means, chop down that
secondary.  Even 30" is on the long side for a 4" secondary, 20-24" is more

There's not enough info about your coil to tell if it is a tuning problem as
well.  What wire diameter did you use on the secondary, and what is your
primary inside-diameter?

Regards, Gary Lau
Waltham, MA USA

>Original Poster: Aric_C_Rothman-at-email.whirlpool-dot-com 
>I started up my complete coil for the first time, with disappointing 
>results.  Vital specs (from memory) are:
>Power Supply:      15 kV NST
>Tank Cap:          0.01 uF styrene
>                    (0.04 uF 40mil dielectric x 4 in series)
>Primary:           18 turns, 30 degree inverted cone
>                  1/4" soft copper tubing, 1/4" spacing
>Secondary:         4.125" dia. x 51" long secondary
>Top Load:          4" x 32" toroid
>Spark Gap:         RQ style, 1/2" Cu tubing, 0.02" gaps, 10 gaps       
>First off, I know the secondary is way too long.  It was the first 
>part of the project I assembled and I didn't know what I was doing 
>(not that I do now ;)
> I tried several different tap locations on the primary, and managed to 
> get a few anemic purple sparks from the top load to the ceiling (about 
>1 foot).
>The PVC tubing around the RQ gap buckled, causing most of the gaps to 
> short out, once this happened, no further sparks from the top load 
>were produced.
>I'm going to build up a new gap, probably consisting of a series of Cu 
>tube section glued to a sheet of phenolic.
>As a first attempt to improve performance, should I slice out a 20" 
>section of the secondary and use that?