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Re: VOMs



Tesla List wrote:
> 
> >From chip-at-poodle.pupman-dot-comTue May 21 21:36:11 1996
> Date: Tue, 21 May 1996 13:24:34 -0600 (MDT)
> From: Chip Atkinson <chip-at-poodle.pupman-dot-com>
> To: Tesla List <tesla-at-poodle.pupman-dot-com>
> Subject: VOMs
> 
> Greetings,
> 
> I have been thinking of getting a new VOM.  Since I don't particularly want
> to smoke it, could anyone make a recommendation?  It would also be nice
> to measure capacitance too.
> 
> Chip


Chip,

Many more modern DMM's (Digital multimeters) are including capacitance 
and inductance ranges nowadays.  I find them a bit on the unreliable side 
compaired to a dedicated LCR meter (Beckman 875A).  A VOM is a classic 
analog needled movemnt type meter with far less sensitivity than a DMM.  
I assumed you meant you wanted a DMM.  The VOM is fast disappearing from 
the scene, much to my disgust, because the metered movement allows a bit 
of optical integration that the DMM just can't do, period.  I have all 
three meter types.  A VOM from Radio Shack should be about $30.00 a real 
cheap DMM might be had from the same source for about the same price or a 
bit more.  An LCR meter of any real quality will run about $80.00 
minimum.  I would suggest an old Heath capacitance checker or a Sprague 
"teleohmike" capacitance checker.  (hamfests for about $10-20)  These 
older "magic eye" instruments were incredibly robust and more than 
accurate enough for the coiler.

Be adived that one single inadvertent check of a cap with a charge 
remaining on it will destroy a modern, digital LCR meter.  The older tube 
units just laugh at such little faux pas on the part of the experimenter.

Richard Hull, TCBOR