Found in Texas Instruments documentation from the 1980s, this circuit applies to digital signal transmission with FSK modulation. The circuit is slow, as it uses period components.
With this circuit it is possible to measure RF signals with a common multimeter. Signals up to 200...
Also suitable for use as a noisy alarm, this Morse Code or telegraph practice oscillator was found...
We show in the figure how to implement a current monitor circuit using only an operational...