Found in a documentation from the 90's, this circuit already includes an amplification stage. The 12 V power supply allows its use in the car.
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...