Found in a Popular Electronics from the 90's, this circuit is used to recognize the frequency of a modulated infrared signal. The LM567 circuit must not be supplied with voltages above 9 V.
This circuit is from a 1965 Argentine publication (Radio Chassis Television). The original...
Very rapid brightness changes or flares that occur on the sun can be detected with this circuit that...
The components of this filter are calculated using conventional formulas (see mathematics section of...