Using the LM3909 this circuit was found in the January 1992 issue of Radio Electronics magazine. Resistor R1 should be chosen according to the table given next to the diagram.
This configuration, which uses a transistorized circuit in the feedback, provides a logarithmic response...
This receiver uses one of the first transistor types available on the market, the CK722, but it...
Suggested by General Electric in 1967 this circuit generates a single pulse when receiving a light signal...