Original poster: "Barton B. Anderson" <bartb@xxxxxxxxxxxxxxxx>
As mentioned my sec is 4.5" x 21.8085" wound with 24 awg. It's 895
turns (had to remove 5 turns due to a pin point breakout right at
the top a few weeks ago when testing other primary configurations).
My topload is 6.25" x 21". It's operating excellent right now using
a static gap (1.25" x 3" copper tubing with .05" spacing between 6
tubes, 0.25" total). It's a vacuum gap. I've found the copper tubing
to be superior to the solid brass which contradicts my statements in
this area previously. The guys talking about thermal superiority
using the copper tubes were correct. So out with the brass. Sure
looked nice though.
Coupling is 0.129. The bottom sec winding and flat primary are even
on the same plane. Free-air spark lengths are around 54" and my son
mentioned a couple days ago that it's the smoothest running coil
he's seen me build. This coil is also wound on a black pvc tube. Cap
size is configured for 0.0188 uF and the inner primary is 1.48" from
secondary (1/4" tubing, 1/4" spacing edge to edge tapped at 8.4 turns.
Take care,
Bart