Abstract: A radio transceiver unit is provided which comprises a housing, a radio unit mounted within the housing; a frequency switch mounted within the housing and including a shaft extending above a top plate of the housing, the frequency switch permitting the unit to operate at any of a predetermined number of frequencies. A frequency selector knob is rotatably mounted on the shaft for indexing the frequency switch to any one of the predetermined frequencies, and a stop device is provided for limiting rotation of the knob to any consecutive series of the frequencies from 1 up to and including a maximum available number less one.

Abstract: A radio transceiver comprising a housing including a front cover, a plurality of interchangeable control panels adapted for selective alternative attachment to the front cover, and a plurality of interchangeable keypads adapted for selective alternative attachment to the front cover in underlying relationship with a respective one of the control panels, wherein each control panel is configured for use with a similarly configured one of the keypads. Each of the control panels comprises a relatively thin planar member having front and rear faces and defined by upper, lower and a pair of side edges, and includes a projection or locking bar extending along and away from the upper edge, and fastening means located adjacent the lower edge. A standardized electronic circuit board is provided within the unit, some or all of the switches included on the circuit being accessible, depending on the particular keypad and control panel employed.

Abstract: A switch assembly comprises an element carrying a pair of hinged switch actuators and a universal devices connector. An outer member, preferably formed of rubber, overlies the actuators and underlies the connector whereby the placement of this switch sub-assembly comprising the element and member in the switch compartment of a portable radio seals the switches in the compartment. Actuation of the switches is accomplished by depressing a switch-actuation area in the flexible rubber member to pivot the underlying hinge to engage and depress an electrical switch. The sub-assembly is mounted in the compartment by a tongue-and-groove arrangement at one end, and a single retaining screw at its opposite end. Flexible electrical circuit carrier leads are threaded through a slot in the compartment wall to interconnect the switches and connector with the internal circuitry of the radio.

Abstract: A control surface for controlling the operation of an electronic apparatus includes a liquid crystal display device and a keypad. The liquid crystal display device selectively changes its light transmittance in response to electrical signals produced by the electronic apparatus in order to provide a visual indication viewable by a human viewer. A light source emits light. A first optical coupler including a specular surface and a light transmissive diffuser is disposed a predetermined distance from the liquid crystal display device. Ambient light passing through the liquid crystal display device strikes the specular surface and is reflected back through the display device toward the human viewer, illuminating indicia displayed by the display device. Light from the light source strikes the light diffuser at a high angle of incidence and is scattered toward the display device, illuminating the display device.

Abstract: A two piece zinc die-cast housing and cover assembly includes an internal center wall structure which divides the included space into two electromagnetically isolated cavities. A VCO circuit sub-assembly and a PLL circuit sub-assembly are each removably affixed to respective opposite sides of the center wall while each is electrically interconnected to the other directly through at least one aperture provided in the center wall. A one piece molded plastic header is removably affixed to the assembly so as to close the remaining side of the electromagnetically isolated cavity and includes apertures through which electrical leads extend from the circuit sub-assemblies for self-aligning connection to sockets or other external electrical connectors. An additional internal metallic shield directly affixed to the VCO sub-assembly as well as other features cooperate to provide an overall improved frequency synthesizer module of this general type.

Abstract: A control surface is positioned on the top horizontal surface of the case of a personal radio. A flexible printed circuit connects the control surface to the internal electronic circuits of the personal radio. A printed circuit board is connected to the flexible printed circuit by a connector soldered to both the flexible printed circuit and the printed circuit board. Some of a plurality of electrical pathways disposed on the printed circuit board are grouped into conductive pairs, while other pathways connect the conductive pairs to the connector. A keypad formed of a sheet of resilient material encases a surface of the printed circuit board. Molded into the keypad are resilient hollow keys, the hollow of each of which contains a conductive pad. When a key of the keypad is depressed, the conductive pad associated with that key makes contact with predetermined ones of the conductive pairs of the printed circuit board, completing an electrical circuit.

Abstract: A housing for a two-way radio is formed of front and rear covers, left and right sides, a base plate, and a top control panel and cover. Certain pieces are provided with corresponding mating surfaces to aid in assembly, and the pieces are held together by screws and nuts. Selected pieces may be substituted to permit variations in internal structure and to provide different configurations without the need to change all of the other pieces.

Abstract: A grill for a loudspeaker has a relatively thick metallic plate with a loudspeaker opening and a plurality of T-shaped bars across the opening, and a relatively thin metallic plate with a loudspeaker opening and a plurality of U-shaped bars across the opening. The plates are mounted together so that the U-shaped bars are located between but spaced from the T-shaped bars to provide physical protection to and good acoustic qualities for the loudspeaker. The relatively thick metallic plate provides a good heat sink for electronic equipment.

Abstract: A reliable but releaseable arrangement for fastening a radio housing and a battery housing together is provided by a tongue and groove respectively positioned at one end of the housings, and by a hasp and catch respectively positioned at a second end of the housings. Separating surfaces are provided on the facing surfaces of the two housings between the one end and the second end so that the housings separate on impact and reduce the shock to apparatus in the housings.

Abstract: The circuit of a portable, two-way radio is selectively connected to an antenna mounted on the radio or to an external antenna by a stripline switch. The switch has a metallic ground plate mounted on the radio, an insulating strip mounted on the ground plate, and a movable metallic plate mounted on the insulating strip. The movable plate is permanently connected to the mounted antenna, and is moved by an insulating plunger. The movable plate movably engages a pin terminal which is connected to the radio circuit and which passes through the housing of the radio for connection to an external antenna connector. When the external antenna is to be connected to the radio circuit, a plug with an external antenna contact is attached to the housing. The plug antenna contact engages the pin terminal connected to the radio circuit. A projection on the plug moves the insulating plunger which in turn moves the movable plate away from the pin terminal to disconnect the mounted antenna from the radio circuit.