RE: ...sounds totally newbie, but...

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

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

If you're just trying to tune the primary, etc... and want to dump the 
energy, why not a resistor in the circuit that provides a load comparable 
to that of the secondary.   I believe that Terry modeled the secondary load 
as a 220K resistor with reasonable success (comparing waveforms against 
spice).. So.. if you could transform that 220K at the secondary to 
something equivalent in the primary.

Another way to choose the resistor would be to calculate the approximate 
reactance of the primary at your approximate resonant frequency and then 
use a resistor that is 10-15 times that (i.e. a loaded Q of 10-15).  Sample 
calculation: 0.08 uF primary capacitor, 200 kHz...  about 10 ohms 
reactance.. so a 100-150 ohm resistor  might work..


At 04:32 PM 1/31/2003 -0700, you wrote:
>Original poster: "Christopher \"CajunCoiler\" Mayeux by way of Terry Fritz 
><teslalist-at-qwest-dot-net>" <cajuncoiler-at-cox-dot-net>
>
>Ok, it's coming back to me now.
>The question that arises now, would be how one might go about
>constructing a "dummy load" that could dissipate the power at
>a reasonable level... and at the same time, be re-useable on
>nearly any other new coil...
>...just a thought.
>---
>C.L. Mayeux
>Owner, MSB Data Systems
>http://www.msbdatasystems.tk
>
> > -----Original Message-----
> > From: Tesla list [mailto:tesla-at-pupman-dot-com]
> > Sent: Friday, January 31, 2003 4:41 PM
> > To: tesla-at-pupman-dot-com
> > Subject: Re: ...sounds totally newbie, but...
> >
> > Without the secondary in place, the gap dissipates almost all the
> > power as
> > heat.  The primary current is also maybe 2X higher.  That is
> > "maybe" ok,
> > but just be aware of it.
> >
> > Operating without the spark gap with resonant sized caps is a sure killer
> > of NST or caps.  But having the spark gap in circuit should
> > protect in that
> > case since the gap will keep the voltage from going too high.