Radio with amplifier (CB20486E)

We found this circuit in a publication of 1991. The audio amplifier is an operational that admits equivalent.

Smart Protector (CB18766E)
This overcurrent relay was obtained in a documentation from the 90's. The sensor consists of a...
Touch or leak alarm (CB22092E)
This circuit was found in old documentation. The SCR can be any of the 106 family. Note the sensor...
300 Hz Flasher (CB6800E)
Found in old documentation, this circuit uses special discharge lamps (neon) of the time. The...