Infrared modulated transmitter (CB7247E)

This simple Philips circuit from the 1960s can use any general-purpose transistor. The signal is modulated at 2.7 kHz.

10 A Bidirectional Current Sensor (CB5261E)
With this circuit it is possible to monitor the charge and discharge of a battery. The circuit is...
Solid state relay (CB8395E)
Found in 90s Radio Electronics, this shield can control high voltage loads in the power grid....
IR Monostable (CB874E)
The duration of the output pulse in this circuit depends on C. This capacitor can have values in...