Re: panel meters

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

Original poster: "Ed Phillips by way of Terry Fritz <teslalist-at-qwest-dot-net>" <evp-at-pacbell-dot-net>

Tesla list wrote:
 >
 > Original poster: "Jim Lux by way of Terry Fritz <teslalist-at-qwest-dot-net>" 
<jimlux-at-earthlink-dot-net>
 >
 > Do you need a scale that reads 300-400, or is a 0-0.5 Amps or 0-500 mA more
 > what you're looking for?
 >
 > Radio Shack has (had?) a variety of panel meters.  You'll have to make a
 > suitable shunt to scale it properly.
 >
 > The surplus places (Fair Radio, C&H, etc.) all have meters in one form or
 > another.
 >
 > If you're looking for a digital meter, All Electronics (among many, many
 > others) has those little LCD modules with 3.5 digits.. their basic
 > sensitivity is 200mV full scale, so you just need an appropriate resistor
 > and diode network.

	Radio Shack meters are quite expensive compared to the surplus places;
swap meet is best place if you have one near you.  A good 3" panel meter
should be worth about ten bucks, give or take, although I've picked up
plenty for as little as a dollar.  Those little LC meters require a
floating 9V power supply!  They are great little devices, but can't
share any power supply connections with the signal being measured.  I've
used a regular 9V transistor battery with good success, but you have to
disconnect it when not in use.

Ed