Re: A Little more than general questions

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

Original poster: "Metlicka Marc by way of Terry Fritz <twftesla-at-uswest-dot-net>" <mystuffs-at-orwell-dot-net>

hi wade,
i'll comment on things i've noticed.

Tesla list wrote:
> 
> Original poster: "Wade B AndB Anderson by way of Terry Fritz
<twftesla-at-uswest-dot-net>" <nabedaw-at-juno-dot-com>
> 
> Hi folks,
>   I am going to turn my questions to the primary and secondary windings.
> 
> By increasing the diameter of the secondary coil, I will increase wire
> resistance, that is a gimme. In what ways does that affect the coil
> operation???
> 
> Why is 1,000 turns of wire the magic # for this coil??? Of course if the
> turns are increased or decreased the inductance is affected, as would be
> the inductive reactance, as is it's ability to establish a magnetic
> field.
> And of course the secondary voltage is directly related to the # of turns
> in relation to the primary.

i asked this same question to the list last year, i wondered why
1200-1600 turns? why not 3000, basically it was a try it and see
situation, so i did. i started with an 8.75" sono tube and used 28g wire
for 3000 turns on the secondary, my thinking was that more turns would
give more induced voltage at the start? secondary inductance of 422mh.
> 
> My question is, what effects ( to the operation of the coil) would result
> if the turns are say.... doubled, or halved???
> 
> On the primary coil how many turns would you all recommend??? Maybe a
> ratio to the secondary???
> And at what spacing???

i used 1/8" tubing for the primary at .350" spacing, this required 158'
of tubing to get the required 25.5 turns to resonate with a primary
inductance of .4090mh. this was with a 50nf cap! if i were to use a more
standard 30 nf cap it would require 32.5 turns and 230' of wire but the
primary inductance would climb to .706mh. i've thought about winding one
because the total diameter would match the height of the secondary at
42".

does it perform any better? i really can't say, with the low currents
with higher voltages i've put into it it doesn't do too bad? but i'm
thinking it should do better. maybe some resistance losses are present,
maybe not, but i didn't get a good chance to do much tuning changes or
topload differences, i messed up by not winding the primary larger
allowing for many different adaptations so? 

also i have a 10-1 ratio secondary with inverted conical primary of 15
deg. that cranks real close to this output so who's to say?


> 
> >From what I can gather from previous responses, it sounds like that a
> flat or coned primary is just a matter of preference??? Is there a
> different affect if the primary windings actually surround the secondary,
> other than the fact that one may risk damaging the primary with secondary
> strikes.
> 
> Thanks, all of your comments are very helpful;

hope it helps in the learning?
marc m.

> 
> Wade