Simple 5V regulator (CB8815E)

This simple 5.6 V regulator circuit was found in a 1966’s Philips. The zener can be changed to obtain other voltages.

Sound Sequencer (CB17981E)
We found this circuit in a 2002 documentation. The frequency of each note is determined by the...
High Power Learning Circuit (CB11910S)
This circuit memorizes the input voltage that is then applied to the load in the form of a...
Call silencer (CB9237E)
This interesting circuit found in American documentation generates a busy signal, without you...