This 1967 Raytheon circuit uses a Raystor, an optical coupler with a lamp and an LDR. The circuit can be adapted to use another type of coupler.
In the figure we have a circuit that allows to interface TTL logic with TTL logic, but with total...
New SAMHA1GxxA Microcontroller Family Delivers Integrated Peripheral Touch Controller for...
With this circuit it is possible to transmit audio signals bidirectionally through a coaxial...