The voltages in an adjusted range in the trimpots are indicated by 3 LEDs. The LEDs indicate when the voltage is below the range, above the range and in the range.
This circuit was found in the March 1982 Radio Electronics magazine. The component is a special...
This 1969 Electronics World power supply has 5 V to power digital circuits and a 170 V output for...
Found in Radio Electronics from the 90s, this circuit uses a thermistor as a sensor that can have...