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Re: Sync gap test



Original poster: FutureT-at-aol-dot-com 

In a message dated 11/30/00 4:58:51 PM Eastern Standard Time, 
tesla-at-pupman-dot-com writes:

> Jon,
>  
>  Will do.  As Bill Wysock pointed out to me yesterday, I really don't know 
if 
> 
>  I am firing at 120 bps or 240 bps right now.  I have no instrumentation to 
> be 
>  able to tell.  Your idea of feeling the rotating electrodes is a simple 
>  solution to this.  I might try running at 120 bps, which means removing 
two 
>  electrodes.  This could be difficult, they are pressed into the rotor disk 
>  quite firmly.  I did try increasing the capacitance last night to .013 ufd 
>  (should be right at resonance) but could not get it to run right.  I 
thought 
> 
>  I had a tuning problem, even when the primary tap was set right where it 
>  should be - according to my calculations.  John Morawa pointed out to me 
> that 
>  I needed to re-set the phase angle on the motor after increasing the 
>  capacitance - which hadn't occured to me.
>  
>  Ed Sonderman
>  

Ed,

You can also tell if the gap is firing at 120 or 240 bps by the
sound.  The 240 bps will give twice the pitch.  Of course you'll
only be able to compare once you've achieved each break-rate,
but I thought I'd mention it.  With the larger cap you're using now,
it will be impossible to keep the NST voltage output low at 120 
bps due to resonance, thus the safety gaps will fire.  At 240 bps
it should be OK.  At 120 bps, you'll need to widen the safety
gaps more than they were using the small 0.008uF cap.  LOw
(120 bps) break rates are more efficient in an optimized system.
For 120 bps, an LTR sized cap of about 0.024uF  or  0.028uF would
keep the NST voltage and cap voltage lower, so that may be better.
I always run LTR (with NST's) now at 120 bps.

JOhn Freau