This simple circuit to monitor the frequency of the power grid uses an analog indicator. The adjustment trimpot can be 4k7 and the indicator is 100 mA full scale.
Found in a 90s Radio Electronics this circuit requires precision resistors in the dividing...
Mouser Electronics is already providing new MOSFETs EF SIHx28N60EF of Vishay series for voltages...
The LMV321 is a low voltage operational amplifier from ON Semiconductor. The following diagram,...