This circuit generates a siren sound. It was found in the April 1969 Radio Electronics magazine. The output signal is to be applied to an external amplifier.
Found in American documentation from the 1970s, this circuit employs an integrated circuit from...
This transmitter uses a small loudespeaker (FTE) as microphone and can send the signals to...
We found this circuit in a 1977 publication. With it we can test general purpose operational...