SSTC - primary and secondary coils

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Original poster: "Chris Swinson by way of Terry Fritz <teslalist-at-qwest-dot-net>" <exxos-at-cps-games.co.uk>

Hi all,


I tried various other coils to see how they would preform. My best working
coil is my 0.2mm 17"high coil ~2000 turns. I tried a 0.4mm 34"high and gave
no spark output. Current draw was only about 1amp from the 30VDC input test
voltage. With the 0.2mm coil I could draw 6amps with 30VDC input. I thought
it may be because the coupling was less since the coil was taller. I put
this to the test and wound a test primary direct ontop of the coil. This
proved to be of no benifit. I went mad and wound about 15" of coax cable
directly ontop of the 0.4mm coil to give the same area of coupling which the
smaller coil had. this proved to work even less than the other 2 primary
tests.

I also tried a 18"high coil wound with 0.4mm wire ~1000 turns and this gave
poor results the same as the previous coil. I also tried a 40"high coil
wound with 0.8mm wire and about 500turns and gave even less results. I can
only assume now that poor coupling is not the reason why the coils do not
work well and it is down to the use of 0.2mm wire with 2000 turns. I would
have thought 0.4mm wire with 2000 turns would work the same if not better
though it doesn't work even with more coupling.

This now proves a interesting puzzel since with my spark gap coil tests the
bigger the wire was the better the results I got were. Now with my SSTC I
can only see that the thinner wire works better. I don't see why 0.2mm
2000turns works better than 0.4mm 2000 turns. With 0.2mm wire I recall the
resistance was very high around 2K. I recall my 0.4mm coil was around 200R
so should give far better results. I now wonder on winding a test coil with
0.2mm with 1000turns to see what would happen. I also ponder about winding a
0.1mm wire coil 2000turns...

What coils do you lot use and what results to you get from them ? Can anyone
tell me what size coils they use, what size wire ( in mm ) and how many
turns they use, plus give me arc lengths based on a fullbridge design with
30VDC input ? I can't beleive that 0.2mm wire works better over 0.4 even if
they have the same number of turns....

Chris