Re: impedance meter

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

Original poster: "Kevin Ottalini by way of Terry Fritz <twftesla-at-qwest-dot-net>" <ottalini-at-mindspring-dot-com>

Justin:
        I presume you really want an inductance meter.

Impedance is the opposition that a circuit presents to ac, including the
circuit's
resistance, capacitance, and inductance. Impedance is the ratio of current
to voltage
in a system.  Impedance is measured in Ohms, like resistance and reactance,
whereas inductance in measured in Henries.  A good example of this is
speakers
... they typically have impedance ratings of four ohms, eight ohms,etc.

A quick Yahoo search for inductance meter circuits turned up:
http://my.integritynet-dot-com.au/purdic/lc-meter-project.htm
http://members.aol-dot-com/sbench102/owens1.html
http://members.aol-dot-com/sbench102/owens2.html

And this poptronics article:
http://www.web-ee-dot-com/Schematics/Inductance%20Meter/IndMeterAdapter.pdf

I haven't tried any of these circuits.  Good DMMs with inductance scales are
pretty
inexpensive these days.  I use a BK Precision 878 at home, but it was about
$225 new.

At work I get to play with an HP 4263B ... about $6K ( you should see the
eyebrows lift when I haul in my primaries and secondaries to measure
them! ).

I noticed that the little Wavetek Meterman 27XT was listed at $119 in the
Mouser
catalog, (as low as $110 street) and it does inductance, resistance,
capacitance
is a frequency counter up to 20MHz (someone also claimed it has a special
range for testing microwave oven Diodes too).
http://www.mouser-dot-com/catalog/cat_606/428.pdf

Wavetek's datasheet:
http://www.metermantesttools-dot-com/downloads/DataSheets/DMM/XTSeries.pdf

This little gem  was also passed around on the archives a couple of years
ago:
http://www.pupman-dot-com/listarchives/1998/December/msg00055.html

and I believe that Ross Overstreet uses one (so it has to be good!).

In my opinion, probably the most valuable $100 tools you could invest in
for TC work.

Kevin

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Saturday, July 28, 2001 12:31 PM
Subject: impedance meter


> Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<Cydesho-at-aol-dot-com>
>
> I drove down to All Electronics store in downtown L.A. the other day and I
> saw that they had a kit there that allows you to use your DMM as an
impedance
> meter even if it doesn't read impedance. I don't have an impedance meter,
and
> it would make things a hell of of lot easier when I'm working on my tesla
> coil. I was wondering if anyone out there knew where I could find a
schematic
> or some plans for something similar.
>                                         Justin