We found this circuit in the November 1992 Radio Electronics magazine. The circuit uses an LDR as a sensor and the transistor can be any general-purpose transistor.
The CMOS 4046 integrated circuit is not very common today, consisting of a very efficient PLL for...
This configuration with complementary transistors causes an LED to flash at a frequency that is...
This circuit was found in a 1968 documentation. It makes use of both NO and NC reed-switches and small...