>Arthur Moe wrote:
>>I have some very vice 1ma meters that I would like to use in my
>>amp project. Question is, which method to use, wind shunts or use
>>them as volt meters and measure the voltage drop across a 1 ohm
>>resistor? Meters to be used to measure both Grid and Plate current.
>Shunts are better when everything is working normally, because they
>produce the minimum voltage drop,
>in the event of current surge (due to an arc or whatever) it's more
>difficult to protect shunted meters effectively using diodes.
Simple shunts also have the disadvantage of one's not being easily able
to calibrate the meter. I like to start with an easy to obtain standard
value such as 0.1 ohms for the shunt, and then calibrate the meter to
read what FS is needed with a series resistor
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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