Found in an Electronic Design of 1964 this circuit has a control for the frequency and another for the active cycle the signal. The bipolar transistor can be a general-purpose type.
This ultra-low power metronome was found in a 1991 documentation. The output transistor is general...
This circuit is very interesting due to the range of practical applications it can have, from...
Found on Popular Electronics in the 1980s, this circuit detects a change in air pressure using a...