By G.K. Bayne, Updated Mar 24, 2022
Analog multimeters use a delicate needle to translate probe readings into a visible scale. The needle crosses a series of markings on the meter’s face, and the point of intersection represents the measured value. Most analog meters are designed for three core functions: resistance, voltage, and low‑current measurement.
The meter’s front face houses the display, a function selector, and two probe connectors. Insert the red lead into the "Ohms" jack and the black lead into the "Common" jack. Rotate the selector to the ohms range and set the dial to the 1X position; 1X means a 1:1 scale. To calibrate, short the leads together so the needle moves to the far right. Turn the "Zero" or "Calibrate" knob until the needle rests on the zero mark. Repeat this calibration before each resistance measurement. For higher values, switch to 10X, 100X, or 1000X; each range has a corresponding scale on the display. Place the probes on the component or circuit segment whose resistance you wish to measure.
Move the red lead to the "Volts" jack and set the selector to the voltage section. Choose the appropriate AC or DC setting based on the source. Many analog meters offer multiple voltage ranges (e.g., 120 VAC, 240 VAC, 1000 VAC). Align the selector with the desired range, then connect the leads across the voltage source. The needle will indicate the voltage relative to the displayed scale.
Analog meters typically support up to 20 A of current. The function selector may have a single position for amperage, but the lead connectors are often marked "A" or "Amps". Ensure the leads are inserted correctly; misplacement can damage the meter. Unlike voltage or resistance tests, current measurements require the meter to be placed in series with the circuit. Use an alligator clip or clamp if necessary to secure the connection. After the meter is inserted, read the current directly from the needle’s intersection with the amperage scale.
