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Re: Stuborn Little Coil!

Original poster: "D.C. Cox" <resonance@xxxxxxxxxx>



You need a "scrap wire" pri of 25-30 turns to find the proper tuning point. This can be a flat spiral lying on cardboard or plywood. Proper capacitance would be around .015-.016 uF, so, assuming you have this value or close to it, then you might need 15-18 turns on the pri depending on your topload. Using scrap wire primaries always allows you to explore the full range of tuning prior to making a fixed pri. If you have less turns than you need you will be plagued with racing sparks and other problems until you hit the proper tuning point.

You could also check the tuning with a sig generator and oscope --- that will get you usually within 1/2 to 1 turn of the correct value.

Dr. Resonance

I scrapped the crap-worth helical primary coil I made,
and swapped it with a pancake at 15 degrees.  Im
tapped at 10 turns with 3 to spare.  I am using a
static gap for now "this is PART of the problem".  My
secondary is 3.5" x 13" wound with 1300 turns.
Coupeling is tight.

Im only getting maby 10" of spark from this coil, and
the spark ain't impressive either.  I am at a loss as
to why this little beast SUCKS so badly.

BTW: this is the same coil I had racing sparks with,
cardboard tube primary was the cause.

Throw some ideas @ me.  Thanks for any thing you've
got.

Coiler Forever: Jeremiah Popp

PS: I STILL NEED YOUR INFO FOR THE "Coilers World Map"
project!!!!!  Remember to put "Private info" or
"Public Info" as the subject.