[Amps] More FS items

[Vic K2VCO]

This prompts me to mention that I've used a lot of meters like this on aluminum panels. 
They read low, and it is easy to modify internal shunts to correct them. Often there is an 
internal shunt and series resistor made of resistance wire, and all you have to do is clip 
a bit off the series resistor.

If you need to wind a new shunt, a single strand of steel "picture wire" works.

I check meters by putting them in series with a DVM and a pot and setting the pot to 
produce a reading at the point where I want the most accuracy. Then I adjust the shunt, 
etc. until the meter reads the same as the DVM.

I know this is obvious, but you can't assume that surplus meters will be correct, 
regardless of the kind of panel.

On 7/24/2012 7:45 AM, Jack/W6NF wrote:
> This meter requires a 50mV shunt*and*  must be mounted on a steel panel
> for proper calibration accuracy.

-- 
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco/