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Re: Inductance and cap. meters

Hi Chris,

	A handheld LCR meter is very valuable for our work.  They are all very
similar.  The B&K 878 is very popular and very well liked by those that
have them.  Techni-tool has them for $275.  The B&K 875A is a simpler
version for $198 from Digi-Key.  There are some less expensive hobbyist
types (Elnico 1801) but I would spend a little extra and get the nice B&K.
The Tektronix B210 digital storage scopes show up on sale at $899.  These
scopes will blow anything else available in the price range (and in many
cases well above the price range) right out of the water.  They are heavily
protected against voltage transients and such.  They measure frequency and
all kinds of stuff saving you from needing another $200 frequency counter.
the $499 analog scopes are cheaper but the B210 will give you ten times the
value.  It is the only new scope I would consider.  For another couple
hundred dollars you can interface them to a printer and a computer.  A
signal generator may be best built out of the Maxim MAX038 IC if you are
handy at such things.  Otherwise, any low distortion audio signal generator
that can go from 10Hz to 1MHz will do.  They are all pretty much the same
so take your pick.  Beware that some of the inexpensive 50 ohm types have a
lot of distortion.  Audio generators have much less distortion but their
output is 600 ohms which is not that big of a deal.  I like the MAX chip
because it can be used directly with less than 1 ohm output impedance which
is nice if you want to measure Q.  However, the nice B&K meter will measure
Q for you (at 1kHz).  A 40kV high voltage probe that plugs into your DVM is
very useful too.  They are $80 from JAMECO.  Fluke makes the best DVMs in
the $150-200 price range (the 20 and 70 series).  Don't worry about getting
too many fancy features.  You want to measure voltage, current, and
resistance.  The rest is best left up to you other equipment.  
	If you are looking at used equipment, it is catch as catch can.  If
something doesn't work, you can buy it for $5 and fix it if you are good at
such things.  Otherwise, used stuff will cost what it costs.  Try to get
the most modern stuff you can and really try to be sure it works.  A giant
HP scope may look neat but repair parts may not be available or the price
may be shocking.  Don't buy those giant ex-military Tektronix scopes.  They
may work and cost only $5 but their size makes them pretty worthless.  You
see them often because nobody wants them.  If they are the storage types
then they may have a use despite their resemblance to a cow (offer them
$10).  In used equipment (and new equipment) the following brands should be
bought if possible:

Scopes - Tektronix
Volt Meters - Fluke
Counters, generators, and other general test stuff - HP or Wavetek

These are the "Best in Their Class" manufacturers.  Shop around for prices
in all cases.  The new prices can vary considerably.

BTW - Don't buy the capacitance only meters.  LCR meters cost just a little
more and you will use the inductance function probably more than the
capacitance.  They also measure resistance at 1kHz which can be useful at
times.  I don't mean to start a thread on who makes the best equipment or
anything like that.  These are just my feeling after dealing with this
stuff for the last 20 years.

Hope this helps.

	Terry





At 11:13 PM 11/13/98 PST, you wrote:
>what type/types of meters are available to mesure this stuff?  I would 
>think they would be necessary for any kind of accuracy when you're aiming 
>for a certain freq. or somthing like that.
>
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