What kind of meter is it?

[uki]

Hey guys !

I got this from an old electronic kit. It had several things, pots, LEDs, bunch of coils to hold components, a small protoboard, ferrite coil, a seven segment display, push buttons,
and the meter in the pictures.

It does read 1.6k ohms. In the display it says I/V so current and voltage.

Does anybody know what kind of meter is this? A galvanometer ?

Thanks in advance !

[PRR]

> ? A galvanometer ?

Yes; except a "galvanometer" is an expensive antique. This is a small cheap current meter. To read real volts you add a series resistor.

Get a 9V battery and a 10k resistor. Wire like this. TAP the last connection to be sure it won't SLAM the meter. Does the meter go up to 77.6% (3/4) of full scale? (Reverse connections if needed.) Then it is a 1milliAmp meter. (If it slams, try 100k, but a 100uA meter is unlikely in a child's project kit.)

[uki]

The device is cheap indeed, the needle was stucking, loosing the screw a bit did the trick, 10k resistor did slam it, 100k did work, the needle go up to about to the 100 and go back to about 1/2 of the full scale. With two 100k in series, it goes up about 1/4 of full scale.
With a 48k it did go up full scale. The needle always go up and back a bit every time the battery is connected.

[uki]

I did read the galvanometer resistance again (about 1655 ohms), with a working needle now, and it does move to about 3/4 of the full scale while reading with a DMM at 2k ohms scale, at 20k goes down to 1/4.

try 100k, but a 100uA meter is unlikely in a child's project kit.)

So 48k means about 50uA, or 5mA ?

Found this http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/ammet.html

What if it is used with high voltage as ammeter, does the shunt resistor need a bigger value? how to find the value?