This circuit was found in Radio Electronics from the 90s. It converts capacitance into frequency in order to obtain a proportional voltage that can be measured in a common multimeter.
This UPS circuit was published in the March 1985 issue of Radio Electronics magazine. The...
Found in a 1965 General Electric Hobby Manual, this timer was originally created to operate with...
This circuit allows coupling optical signals to a TTL input with excellent performance. Among the...