Abstract: A portable interconnection system has a housing having and a plurality of communications ports adapted for connection to a plurality of audio communication networks; electronics substantially enclosed by the housing; the electronics including at least interconnection electronics operative to selectively establish a plurality of independent connection sets, each connection set interconnecting at least a plurality of the communications ports for communications between a plurality of audio communication units operating in at least two different and incompatible ones of the audio communication networks; a user interface connected to the interconnection electronics and operative to control the interconnection electronics; wherein a combined weight of the housing and the electronics is not more than fifteen pounds. A display may show an interconnection status of the plurality of audio communication units for a plurality of the independent connection sets simultaneously.

Abstract: A scanning FM monitor receiver is disclosed which is of the superheterodyne type and is capable of scanning and receiving a plurality of channels on a plurality of bands. The receiver incorporates a phase-locked-loop frequency synthesizer which eliminates the need for crystals for every channel. The input data that the synthesizer requires to develop the individual preselected frequencies is provided by a random access memory that is programmed by the user for the frequencies desired. Indicator lamps on the receiver illuminate when a channel is being scanned and also provides a visual accuracy check when an operator programs the random access memory with the data codes for producing the various frequencies.

Abstract: A scanning FM monitor receiver is disclosed which is of the superheterodyne type and is capable of scanning and receiving a plurality of channels on a plurality of bands. The receiver incorporates a phase-locked-loop frequency synthesizer whih eliminates the need for crystals for every channel. The input data that the synthesizer requires to develop the individual preselected frequencies is provided by a random access memory that is programmed by the user for the frequencies desired. In one embodiment, decimal frequency information is entered on a numerical keyboard and converted into binary form for programming the memory. Indicator lamps on the receiver illuminate when a channel is being scanned and also provide a visual accuracy check when an operator programs the random access memory.

Abstract: A scanning FM monitor receiver is disclosed which is of the superheterodyne type and is capable of scanning and receiving a plurality of channels on a plurality of bands. The receiver incorporates a phase-locked-loop frequency synthesizer which eliminates the need for crystals for every channel. The input data that the synthesizer requires to develop the individual preselected frequencies is provided by a random access memory that is programmed by the user for the frequencies desired. Indicator lamps on the receiver illuminate when a channel is being scanned and also provides a visual accuracy check when an operator programs the random access memory with the data codes for producing the various frequencies.