Original poster: Sparktron01@xxxxxxxxxxx
When I first started coiling ( late 60's - telling age :^? ) had very
little success with "home brew" systems (even built the "Big TC that was
in Popular Electronics, best I could ever get was ~ 12"). I built at least 3
from scratch systems with "zero, zilch, nada" to show for the effort
until...
I did finally successfully build a TC using a 5kV 30mA NST, glass plate
caps in
a cigar box (2-3nF at max), while a senior in HS. I used a needle
electrode (BAD) but put a fan in front of it for cooling (GOOD) and also
put steel bolt in center of primary and secondary to boost coupling.
I could get about 4-5", and actually could see the effects of:
1. Good quenching (turn fan off, spark length was cut in half).
2. The utility (NECESSITY!!!) of being able to tune the system
(I believe this one factor was the major design issue with the Big TC
machine, other then sucky SG design, and glass crap caps).
3. I put a small tophat allumum pulley on coil and could see longer
sparks, and benefit of top capacity.
This small system was an incredibly illuminating (no pun) project, and a
real joy (BLAST) to run. And actually had pretty good (maybe even high)
performance considering the state of knowledge of TC's at the time.
At this point (staring EE in college), I felt we would eventually gain
understanding of these deceptively simple (but damnifyingly complex)
transient circuits. Finally are getting close, still ALOT left to
research, particularly in SS realm... only 30+ years later...
OBTW, other then mechanical sizing of components (measuring and cutting
parts), not ONE calculation on the electrical side, from the outlet to the
HV electrode.
Best Regards
Dave Sharpe, TCBOR/HEAS
Chesterfield, VA USA
> Original poster: "Derek Woodroffe" <tesla@xxxxxxxxxxxxxxx>
>
> Have any of you guys ever just built a good TC by trial and error?
>
> Yes I have made a couple of TC's and an SSTC by trial an error,
> using bit I had lying around.
>
> But when I started coiling, I tried much the same things and had
> many total failures. Even with trial and error you must start with
> components in the right ball park, you can then fiddle to get them > right.
> I'm sure most of us on the list who have built a few coils could guess > at
> the frez of a secondary, pick a primary that'll be about right, and be > in
> the correct order of magnitude for a primary cap to match. This is due > to
> experience. Even then you probably wont get the max out of the coil.
>
> Without the experience, you can save yourself a lot of time and play
> with some numbers in JavaTC, WinTesla or similar. Its much quicker in > the
> end, believe me..
>
> Derek
>
>