Re: super cheap capacitance/inductance Tesla coil metering

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: robert heidlebaugh <rheidlebaugh@xxxxxxxxxxxxxx>

Think analog...Cheep test equipment can be made. a capacitor across a
voltmeter as a load will read frequency if you use a constant amplitude
input. clamp the input with a zener and a input resistor/diode. since the
input is pulse DC only frequency can charge.  the capacitor over the
discharge of the meter . If you like parts a LM555 in the one shot mode can
produce  the DC pulses to charge the capacitor. More pulses per second
produces more average charge. or frequency indication. This is not for
digital only analog meters, but I have used it for over 50 years for rough
quick measurment. Harbor freight has a capacitance meter available cheeper
than you can build one.
   Robert   H--


> From: "Tesla list" <tesla@xxxxxxxxxx>
> Date: Tue, 29 Nov 2005 16:58:26 -0700
> To: tesla@xxxxxxxxxx
> Subject: super cheap capacitance/inductance Tesla coil metering
> Resent-From: tesla@xxxxxxxxxx
> Resent-Date: Tue, 29 Nov 2005 16:52:45 -0700 (MST)
>
> Original poster: Terry Fritz <vardin@xxxxxxxxxxxxxxxxxxxxxxx>
>
> Hi All,
>
> Making an oscillator with a 555 timer to measure capacitance is on my
> mind.  I "think" it could do inductance easily too...
>
> I was thinking of a trivial LM555C timer circuit powered by a 9V
> battery that would plug into the sound card jack of a computer to
> read the frequency.  A little program might be able to do the math 
directly...
>
> Thus, one might be able to make a LC meter for like $5 which I think
> many of us would like.
>
> There is probably some free program out there that does the "sound
> card input jack to frequency readout" function????
>
> Everyone has a sound card these days and plenty of resistors protect
> the computer...  So the "high level" hardware is already done...
>
> I suppose such a thing could be made into a Tesla coil primary and
> secondary "tuner too"...  A PC with a sound card plus some cheap and
> easy "Radio Shack" parts is a pretty powerful machine!!! It really
> could be a sound out cable to alligator clips and a resistor
> protected similar input cable if you had nice software...
>
> I know the hardware side, but not the software side...
>
> Hmmmm....
>
> It would be a cool addition to Tesla coil design programs...  I would
> love to be able to send out $10 worth of stuff for someone to hook to
> their coil and it would read back everything we need to know about it ;-)))
>
> Just a thought...
>
> Cheers,
>
> Terry
>
>