Re: Frequecy counter, measuring 2ndary output

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

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <FutureT-at-aol-dot-com>

In a message dated 5/21/01 11:17:06 PM Eastern Daylight Time, 
tesla-at-pupman-dot-com writes:

> Trying to measure the BPS is a more difficult task.  I've also asked but
>  found no way to directly measure this with a counter.  The best way is
>  to use a single-sweep storage or digital scope.  Lacking that, Richie
>  Burnette has used an audio tape recorder to record the gap sound, then
>  played that into his PC's audio recorder.  This allows the ampitude
>  peaks to be seen and counted over some interval of time, thereby
>  indicating the BPS.  Haven't tried this myself but sounds simple enough.
>  
>  Regards, Gary Lau
>  MA, USA 

Gary,

I would think it would be easy to make a hand-held device, using
a photocell and a self-designed counter circuit to count the light pulses
from the spark gap to measure the bps.  A low pass filter would
be used so the RF or notches are ignored.  THe device would
count for a given amount of time such as 1 second, and would
read out how many firings occured during that time on an LED
7 segment display.  I've always been meaning to build one, but
never got around to it.  There would be a sensitivity and reset
button, etc.  All built into a small metal box with battery power.

I was also thinking of making a similar device to measure quench
times.  The firing of the gap would start the clock, etc.

John Freau