Re: 3 probably awful beginners questions ;-)

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Christoph Bohr by way of Terry Fritz <teslalist-at-qwest-dot-net>" <cb-at-luebke-lands.de>

First, thank you very much everyone for your quick response and the time you
spent helping me with my probs.

Due to the many questions I decided to anwer in one mail to all the
questions.
I hope this is not too confusing as I took statements from all your mails.

 >Assuming that you're using a static gap, using a larger power supply (i.e.
able to source more current) will definitely increase performance. If more
current is available, whatever cap you're using will still charge to the
same voltage, but it will do so more times (bangs) per second, and this
results in longer streamers.

Finally I got that, too. I was thinking I could only charge the cap
according to the mains frequency 100 times per second ( each half-wave at
50Hz )
I use a static gap as a RSG seemed not neccesary to me at these power
levels.


 >Would you be using air core chokes?  I did briefly and had all kinds of
arcing where it should not have.

I do because someone strongly encuraged me to do so, these are 2"
PVC-tubings I wound 40 turns on. The wire is the core of a RG58 ( thin
ethernet ) cable which seems to have an very goot insulation on it ( but
might be too thin ). Anyway, I will try without them an see what happens.

 >I assume your primary is a flat pancake design?  Is it possible that the
pri-sec coupling is too high?

I have build a primary in conical shape with 8" inner and ca20" outer
diameter, 13 turns, 6" high. The exact coupling I didnt worry about until
now because I didn't really understand why a higher coupling coefficient
might be a bad thing.

 >If the distance between primary and secondary is 3", there should be no
problem arcing due to arc voltage distance, but then I'm guessing at your
primary style. Maybe some more info will help point to the problem. Maybe
list the primary type style and position up and down in relation to the
secondary.

The most inner winding starts 1/2" above the Plate it is mounted on and the
secondary starts  2" above the mounting plate.


 > 2. With my coil, I get about 1/2 turn change on the primary where the
 > performance seems to be the same.  If I find the best performance at say
 > turn 7.5, there is a noticable difference at turn 8.5 or turn 6.5.  Your
 > primary components should be mounted as close together as possible and
 > connections should be made between them with at least # 12 or #10
 > wire.  What is the primary wound with?

I used 6mm ( must be around 1/4" ) copper tubing like its used for the
connection of ice-cube-makers to the wall outlet for water.
Another ( typical european question ) what does #12 mean? is that 0.12
inches ?
The components are arranged within an small table I built, so the
connections are very close together ( less than 2" from the one brushing of
the cap to the inner tap of the primary )
But I used HV-wire like its used in neon signs, probably way to thin for
this purpose, I'm definitely going for some more 1/4" copper-tubing to be
used for these connections.

 >
 > 3.  You are correct, the inner turn of the primary should not be arcing 3"
 > to the ground point of the bottom of the secondary.  I think I only have
 > about 1.5" of clearance there.  What kind of ground does the secondary
 > have?  I ran some numbers, making many assumptions, and found that your
 > coil should be tapped at turn 10 or 11 on the primary.

really astonishing ;-) I really use the 10th turn at this time. my
calculations unfortunately were never that precise...

so far thank you very much, I hope tomorrow I can make a next test run an
see how your tips work out .

Christoph Bohr