Under this name, Radioelectronics magazine published in the January 1974 issue a light exposure meter for photographers. The circuit used general-purpose transistors and a FET, with an LDR sensor.
This circuit is from a 1977 application manual for timers. The circuit provides a negative pulse...
The sensor of this circuit is an NTC with a resistance between 200 and 1000 ohms. The resistor R1 must...
This receiver can operate with the transmitters shown in previous articles and even others...