[TCML] Non-DR SSTC primary - interesting facts

[TheBypasser <bypasser@xxxxxxx>]

Well, upon an attempt of further civilizing my flower-pot primary I  
removed a turn (getting 6 turns instead of 7) and blew two fets (was a  
pretty stupid idea - even the primary itself lost ~25% of it's inductance,  
first blow on the finished construct btw) - and the interesting part is -  
the spark almost didn't grow (was up to 60cm - remained the same). Of  
course I put the turn back and replaced the fets (working fine again, same  
spark - and the heating of the bridge is very subtle btw, even with my  
really bad cooling), but it led to some interesting thoughts, also based  
on my older research.
The idea is - you have a fixed-height primary with a significant number of  
turns and start reducing that number one by one, keeping the height  
constant. At first you get a low transformation coefficient and high  
inductance, thus the power is too low. As you remove the turns, the  
transformation coefficient gets higher and therefore the power transfer  
into the secondary increases. That's good, but - you slowly increase the  
reflected power by doing that, therefore the SWR gets worse and worse,  
making LESS power supplied into the secondary. The question is - is the  
resulting power supplied into the resonator rising all the time, or  
there's a peak after which you start making the coil be able to transfer  
less power again? By the way (didn't test that on my new coil, actually as  
far as it's working well and never blows I'm not going to change much -  
60cm on a bps up to around 30 with a pretty high pulse length feels like a  
proper result for a bridge of 30a fets ;) - and the secondary heats up  
pretty much anyway) the tests on the previous version of this coil (there  
was no feedback at the point, and the secondary was much smaller and ran  
at ~300kHz instead of the present ~150) showed that the primary height  
(meaning not how high the top turn is, but the distance between the top  
and the bottom turns - eg the top turn remained at ~1/4th of the  
secondary, but I tried both spreading the primary to the bottom of the  
secondary and winding it tight) doesn't affect much as long as the winding  
remains close to the secondary..
So, is there a point of an "optimal" primary, at which further turn  
reduction has only negative effects?
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