This circuit was found in a 1965 Electronic Design. What it does is respond only to positive pulses (above zero volts) and can be used in automation systems.
This circuit uses unusual operational amplifiers, but equivalents can be tried. FETs can also be...
This circuit was obtained in a 1991 publication. What it does is to amplify a signal with unit...
This small digital transmitter uses a 1 MHz crystal, or another nearby frequency, to produce a...