This filter for receiving audio in telegraphy was found in a magazine 73 for radio amateurs, in an edition of the 80s. The circuit is tuned to 700 Hz and has a 200 Hz bandpass.
This circuit activates a garage door by the car headlights car or a lantern. The circuit is from a...
We found this circuit in the March 1992 issue of Radio Electronics magazine. The circuit has a...
This circuit was found in a 1965 Electronics Design. The configuration can be applied to current...