An analog voltmeter might look like an antiquated piece of test equipment; however, you can use it to get very accurate readings--as long as it is properly calibrated. This simple guide will show you how to calibrate an analog voltmeter.
Step 1 - Attach the Probe Leads
Attach the red and black leads to the analog voltmeter in the appropriate slots. The slide for the red probe will be marked with an "A" or "V," and the other should be labeled as ground (GRND). The ground slot is for the black probe lead.
Step 2 - Turn on the Voltmeter
Switch the power switch for the voltmeter to "On."
Step 3 - Switch to the "Ohms" Selection
Turn the dial on the voltmeter to the "Ohms" selection.
Step 4 - Check the Voltmeter's Calibration
Next touch the black and red probe leads together. If the analog voltmeter is correctly calibrated, the reading should be "Infinite Ohms" when the probe leads are not touching, and should drop all the way down to "0" when the two probe leads touch together. If the reading is more than 0.05 ohms when the probe leads are touching, the voltmeter is not correctly calibrated.