coverting analog to digital meters on old test equipment

[trog1058]

any material that can help pick the best meter to replace analog meters?

[Signal32]

You mean something like this ? http://www.aliexpress.com/item/Green-LED-display-Color-DC-0-4-3000-33-000V-0-36-Digital-Voltmeter-three-Wires/1320678280.html

[trog1058]

I was thinking of material that shows if I need voltage or current for different types of test equipment. If a meter is plus and minus is there a digital replacement.  Just a book or pdf that would bring me to the best type of meter for what ever type of analog is to be replaced.

[barry14]

It is unlikely that you will find literature directly useful to you for this issue.  Each meter will have to be considered on an individual basis.  Analog meters can vary widely: some are designed to read voltage and have a relatively high input resistance, some are designed to read current and have a low input resistance.  In many cases, there are external resistors that set the type of reading and the range scale. Some meters have zero at the center.  The damping of the meter may be significant in some applications so replacing it with a digital meter may be difficult. Also, some meters are designed to be used to set a peak or a null; again these may be difficult to replace with digital meters. To repeat, there is too large a range of possible analog meter functions to generalize how to replace them with a digital meter.