This circuit was obtained from a 1967 General Electric manual. The circuit uses components of the time, but equivalents can be used, for example, a BC547 for the transistor and a TIC106 for the SCR.
This circuit generates 5 notes in sequence, which are programmed in the connections of the 4017...
This circuit with low-slip characteristics uses an operating system that is not very common today....
Found in ancient American documentation, this circuit uses an operational amplifier of the time,...