Re: Solid State - No Current Limiting..

>Paul if you >> just feed the 4428 a square 
>how do you do current limiting? 
>I won't get much chance to play for a couple of weeks - first my wife's parents
>and then my parents are coming for a week :) but I've had to clear my
>from the spare room :( .

Bummer   :(

>Have fun,
>Alan Sharp. (UK)


My driver does not have any current limiting.
I'm not shure where the current limiting is needed.
Do you drive your secondary like an induction coil?
If so why?

The driver i have been experimenting with uses a push-pull setup
to drive a clamshell transformer. The output of the transformer
is your basic square wave. (same freq as resonate freq of secondary 
of tesla coil). This square wave is then put through a low pass
filter. The output of the low pass filter drives the primary of the 
tesla coil at it's res freq.(primary has 3 turns for one I am playing with)

The low pass filter thing is to remove the harmonics from the square wave.
set the filter rolloff at  2X the res freq.

I have been playing with setting this filter at the res freq but the 
voltage buildup caused by this melted my little 1KV (25 cent looking) caps.
And the current saturated my clamshell. (got very hot very fast!)

try it and see if you like
its not for me im tring to build a coil that requires nothing special ie 
High current carring caps, massive step up transformers.

Have fun 

Paul Harriman EE