Re: Small coil and Primary

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

Original poster: "Jim Lux by way of Terry Fritz <twftesla-at-qwest-dot-net>" <jimlux-at-earthlink-dot-net>

There is some measured data from HEI coils on my web site at:
http://home.earthlink-dot-net/~jimlux/hv/igncoil.htm


Tesla list wrote:
> 
> Original poster: "Ben McMillen by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <spoonman534-at-yahoo-dot-com>
> 
> Thanks everyone for the help with the oil.. ;)
> 
>   I started building a table top coil that I want to power with an
> HEI/dimmer setup for the HV supply.. I've wound a secondary on a piece of
> 2" PVC with 31GA wire.. winding length is 10" (~1000 turns if I remember
> correctly).. resonant frequency is about 526KHz with a 2.5" doorknob as a
> topload.. Here's what I need to know:
> 
> 1. How do I go about measuring the secondary inductance of the HEI so that
> I can be sure of being LTR? Does LTR even matter with such a small coil? I
> think I remember a site somewhere that had the measurements worked out for
> 60Hz and 1KHz..
> 
> 2. What is the most efficient primary design for a coil of this size? I've
> seen a few coils with a helical primary.. does anyone see any problem with
> this?
> 
> 3. Would a small NST or OBIT be a better choice for a HV supply? I don't
> know how much current an HEI's secondary can put out before frying.. If I
> remember correctly, the output power depends on the size of the motor run
> cap that's in series with the dimmer and coil..
> 
> Again, thanks for any help..
> 
> Coiling In Pittsburgh
> Ben McMillen