This circuit produces the sound of a motorcycle or an outboard motor. The frequency is adjusted in the pot. For supplies above 9 V the BD136 must be equipped with a small heat sink.
The circuit is from old documentation from the 70s, but the components are still common, as the...
This circuit uses a common cathode display and TTL integrated circuits. We found it in a 2001...
We found this circuit in Popular Electronics from 1992. The circuit uses general purpose...