The integrated circuit and configuration are uncommon. However, the sound quality is good. The circuit is from the 1983 Intersil Databook. The output transistors must be provided with heat sinks.
This circuit is from a 1977 timers Cookbook, but can still be easily assembled with the eventual 3130...
This circuit can be used to activate the lamp when it gets dark. We found the circuit in old...
This adjustable source was found in a 1979 documentation, but all components are still common...