Abstract: A wall switch is provided for an automatic lighting control system for a space equipped with multiple lamps for illuminating the space and multiple power circuits for supplying power to different groups of said lamps. The wall switch includes at least one sensor detecting conditions or events that indicate that increased illumination of the space by the lamps is needed or decreased illumination of the space by the lamps is allowable. Normal control of the electric lighting is thus automatic to a large degree. But, at least two manually operable switches are coupled to the microcontroller to provide the microcontroller with ON and OFF command signals for at least two of the lamp groups powered by different power circuits. A separate status indicator light for each of the switches is controlled by the wall switch and provides an indication of whether the lamp group associated with each manual switch is currently ON or OFF as a safety and economy feature.

Abstract: There is disclosed a shroud and housing assembly which is attached to or forms an integral part of the front sidewall of a hands-free telephone subset. The shroud assembly contains a trough which is directed along the length thereof and which terminates at one end in a housing for a microphone or similar device. The shroud has a flanged wall integrally secured to the microphone housing for accommodating an electret condenser microphone. The shroud section is further supported by means of upstanding posts which are connected to the sides of the or flange by means of thin webs. The posts and webs act to strengthen the housing while further providing support to prevent undesired vibrations which emanate from a loudspeaker contained within the subset housing from coupling to the accommodated microphone. The reinforced housing minimizes the coupling of mechanical borne vibrations between the subsets loudspeaker and the microphone.

Abstract: This invention is a technique for providing isolation between the two channels of a handsfree telephone subset without resorting to gain switching or gain variations in the transmission path. The invention involves separating the frequency spectrum into two portions and allowing the stronger signal to capture a major portion of that available spectrum. Switched capacitor filters are used to control the degree of frequency bandwidth allocated to each channel while the filters are clocked from a common source assuring no possibility of overlap in the frequency spectrum. The affect of varying the bandwidth is much less noticeable than varying the amplitude and, therefore, creates much less user irritation.

Abstract: A handsfree or loudspeaking telephone circuit employing loudest speaker comparison for controlling the direction of transmission of speech signals. The circuit employs the speech network for the handset to provide gain and hybrid functions. The circuit contains logic for controlling the switching between handset operation, handsfree operation and call announcing operation.