zeitler@ibm.net wrote:
>
> Is there a simple way to accurately measure the low resistance of a current
> meter shunt? I am trying to get my plate current and grid current meters
> calibrated and I need to verify the values of the shunt R but the Ip shunt
> is less than .3 ohms and the Ig shunt is less than 1.6 ohms. My Fluke 77BN
> is of no real help at these low values.
There are ways of doing it, but maybe you should consider a different method:
Put a 1 or 10 ohm resistor in series with the circuit. Then use a multiplier
resistance to convert your milliammeter to a voltmeter and read the voltage drop
across the resistor:
|
|----------^^^^^^^---------|
> multiplier |
< 1 or 10 ohms M
> |
|--------------------------|
|
The multiplier is normally a relatively high value of resistance, so it's easier
to get it right. The ARRL handbook discusses this method as well as the
traditional shunt.
73,
Vic, K2VCO
Fresno CA
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