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.

Digitally controlled mixer (CB9036E)
This circuit, which can be used as a shield, was found in American documentation from the 1970s....
FSK Generator XR2206 (CB24511E)
This circuit for low frequency data transmission was found in the May 1977 issue of Radio...
Automatic light (CB24332E)
This circuit activates a relay that has a lamp as a load. The circuit is from a Radio Electronics from...