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Re: measurement tools was:NST resonance - Terry's testing

Original poster: "Jim Lux by way of Terry Fritz <twftesla-at-uswest-dot-net>" <jimlux-at-earthlink-dot-net>

Hall effect current sensors have bandwidths up into hundreds of kHz, and run
about $20-30.  They are normally used for current sensing in switchmode
power supplies.  They typically run off of some DC supply voltage (like +/-
12V) and produce a buffered voltage output proportional to the current in
the wire that is run through the hole in the middle.

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Sunday, February 11, 2001 6:00 PM
Subject: Re: NST resonance - Terry's testing

> Original poster: "Terry Fritz" <twftesla-at-uswest-dot-net>
> At 07:19 PM 2/11/2001 -0500, you wrote:
> >
> > Bart & All,
> > I'll second that! Many of my toys are of same vintage as Tesla himself.
> > hand-rubbed, dove-tail-jointed oak meter cases are beautiful, but the
> >
> > work has dry rot. Would anyone have a short list of what toys a modest
> > retired) but modern TC shop should have? On or Off-list answers OK to
> > space.
> >
> > Sparks in the Hills of West By G-- Virginny
> > Matt D.
> Hi Matt,
> First I would get a good multi-function meter.  The wavetek 27XT is highly
> recommended by many (I don't have one) for about $120.  It does
> inductance, frequency, and the usual functions.
> A scope of any vintage is really neat along with a sine wave generator,
also of
> any vintage, that will cover TC frequencies.  The "audio" signal
> will work well.  My new tuner (not done yet) will find the same resonant
> frequencies but a real scope and generator are great fun to play with.
> I have a high voltage 40kV DVM probe I use a lot.  They are advertised for
> color TV work but they can measure NST voltages easily where nothing else
> I think they run about $100.
> One thing to be careful of is not to buy an expensive used device that is
> match for a new modern device.  My Tek TDS 210 cost $1200 (used to be
> but you can easily find 10 year old scopes used for $5000 that can't do
> what it can.  You can also find new analog scopes in the $1000 range new
> aren't even worth looking at anymore...  My arbitrary function generator
> $1700 but I won't even mention what you can find the 10 years old used
> costing!!  I don't know how they sell some of those old things...  It is
> like you wouldn't want to pay $3000 for a PC from the 80's that cost
$10000 new
> but is now really worth 10 cents...  My stuff may seem expensive, but ten
> ago the same stuff would have cost 10X that!  Unfortunately, trying to
find the
> modern toys used for a low price is very hard!!  One place actually wanted
> for a used 33120 arb than the new book price :-))
> There are a lot of probe options too.  Current monitors and probes are
neat but
> hard to find.  I really like the Tek P5100 probe.  Probably hard to find
> and $250 new but worth every penny!  Current monitors you will have to try
> find used.  Pearson's are even out of "my" price range!
> A digital camera is really neat too since you can take pictures of stuff
> share them electronically.  Some good basic ones work very well and they
> getting inexpensive.
> My fiber probes and plane antenna's are cool too.  The antenna is very
> inexpensive.
> So I would start with the basics and work your way up and get the stuff
> want to satisfy your area of interest.
> Don't forget that much of the stuff can also be made yourself very cheaply
> there are a few tools you will have to buy.  I have made a lot of homemade
> signal generators but the new one I got beats them all 1000 times over...
> Cheers,
>         Terry