This circuit was found in General Electric documentation from the 1980s. The circuit is intended to receive 50 kHz modulated optical signals. The components support modern equivalents.
This 1967 Philips circuit recognizes a light signal (visible or infrared) modulated by tone. The...
This circuit turns on an old cassette recorder when the telephone rings, thus enabling the...
This is the receiver for the previous circuit transmitter. Similarly, no information about the...