Wattmeter (T1351E)

This circuit is from a February 1949 Radio Electronics magazine. The circuit uses 3 tubes and includes the power supply.

Economic Timer (CB16468E)
This timer uses common components today. It activates a relay after intervals that can be adjusted up...
AD7779 24-bit ADC Simultaneous Sampling (COM116E)
September 2016 - It can be obtained from Mouser Electronics the new ADC AD7779 from Analog Devices with...
Battery Saver (CB7134E)
Found in Popular Electronics from the 90s, this circuit consists of a timer that turns off the...