Abstract: A system and method for controlling and distributing the entertainment signals from a plurality of electronic entertainment devices to a plurality of remote locations within a building; A host controller combines the respective entertainment signals from a plurality of sources, such as a satellite receiver unit, a video cassette recorder and a rooftop antenna, to provide a mixed output signal at a relatively constant impedance. The mixed output signal is transmitted along a single coaxial cable to a plurality of remote locations distributed along the cable. Each remote location includes an infrared detector for receiving infrared control signals from a remote control transmitter for controlling the corresponding entertainment device. The infrared detector converts the infrared control signals into corresponding electrical control signals and transmits the electrical control signals back to the host controller on a second conductor which is also included within the coaxial cable.

Abstract: A radio receiver for frequency modulated signals in which direct conversion techniques are used to provide zero I.F. quadrature baseband signals I & Q. The I & Q signals are limited (11,12) to form square wave signals and pulse forming networks (13,14) derive pulse sequences the frequencies of which represent the polarity changes in the square wave signals. Each square wave is multiplied (15,16) by the pulse sequence derived from the other square wave to produce a unipolar pulse train. The two unipolar pulse trains are combined (17) to give a digital output signal the frequency of which is equal to the sum of the frequencies of the two pulse trains. Low pass filtering the output signal produces a simulation of the original baseband modulation.