Found in a 90s American documentation, this circuit uses an integrated from the time that is difficult to obtain today. The sensor is a common photodiode.
Here is another project that is based on an astable multivibrator, in a demonstration of the...
This circuit was found in an Elektor from the 90s. It is a circuit that generates different types of...
The circuit shown in the figure converts a sinusoidal signal of convenient amplitude into a CMOS...