Simple good volts/ohm meter

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neazoi

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Is this circuit considered a good simple voltmeter or not? Any other better alternatives (but still discrete components and easy to be built at home)?
 

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looks fine - finding a decent meter movement may be tricky these days ...
 

    neazoi

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I have seen very cheap price and awful quality Asian ones and good price good quality Russian ones.
How do you define a good movement? What are the parameters?
 

1.
Store-bought multimeters have a single 18-position dial for selecting ranges. For convenience it's hard to beat.
As for your schematic it has several switches to keep track of. Forget to check one and you could burn up something.
Furthermore 5-position switches cost several dollars new.
It depends on how much you desire the FET input.

2.
To print/write so many numerous scale markings is a challenge. And you want to verify calibration against a known good meter. Preferably a DMM (personal note, for instance my Radio Shack D'Arsonval meter has a goofy spring which gives linear response over most of the scale except near maximum deflection when it reads 5 percent low).
 
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    neazoi

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it has to be a 50uA movement for starters with a large swing of arc to usefully see results and well damped if possible
 

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