The ubiquity of integrated circuits in all things electronic has led to a flood of lower-cost digital models. However, there are still times when a digital, analog, or hybrid analog/digital meter ...

This is a take-off on Mr. Marian’s “Simple Micro Ampere Meter Circuit” that utilizes active circuitry and an analog meter to make sensitive DC current measurements. A reader subsequently asked if it ...

Here is a useful circuit for ... a simple digital voltmeter, which can safely measure input dc voltages in 0 to 30V range. The Arduino board can be powered from a standard 9V battery pack, as usual.