Found in a 90s Electronic Design, this circuit can generate sinusoidal signals from 0.1 Hz to 25 kHz with low distortion using a MA292 from Maxim.
With this circuit it is possible to use a common hair dryer as a hand dryer. The circuit is timed...
This circuit was obtained from an English magazine from 1979, but can be easily assembled today...
This circuit was obtained in a 1975 magazine, but it can be easily assembled using BC548...