This is a very simple. The IC UM3561 produces four differen sound effects, the output at Pin 3 being amplified by the transistor 2N2222. A 64 ohm loudspeaker can be substituted in place of the 56 ohm resistor and 8 ohm loudspeaker.
The IC sound generator UM3561 is now available in a kt from Maplin Electronics. Click here for the link.