Hi Thomas,No problem. Thanks for letting me know. Certainly makes a difference and your numbers now do end up at 15 turns/cm.
Something I noticed however, the distance from the bottom of the secondary to the edge of the beginning of the primary looks to be about 5.5cm which is wide and makes for a low coupling of 0.08 along with the primary about 1cm below the secondary? I would recommend raising the primary to where the primary is 3cm "above" the secondary which would put k at 0.123. That seems extreme, but it's not with your geometry. Should tune in at about turn 3. It would be nice if you could use a few more turns out of the 8.4 you have now, but due to the situation you really can't. Normally I would say get rid of all those extra turns as it is a little extreme, but the fact is those extra turns add some external C to the coil and allows more turns to be used. So I would just leave them alone for now.
It would be nice to rewind the primary if possible starting the primary at about 2 to 2.5 cm away from the secondary and then setting the pitch to 13mm (center to center) or basically where the spacing edge to edge equals the wire diameter. No need to have such large spacing between turns.
Spark gap needs some work, but you already know that. Take care, Bart Thomas Ryckmans wrote:
Bart,Really sorry to have wasted your time; the diameter of the secondary is 70mm not 130 mm.Using the inductance calculator here http://deepfriedneon.com/tesla_frame6.html I get 3.2 uH with Diameter=70 mm, 480 turns, 15 turns/cm, 32 cm heightReally sorryThomas _______________________________________________ Tesla mailing list Tesla@xxxxxxxxxxxxxx http://www.pupman.com/mailman/listinfo/tesla
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