Abstract: A battery charger for recharging nickel cadmium batteries includes trickle charge, fast charge and deep charge modes. A control circuit responsive to the terminal voltage of the battery includes a clock-driven mode control counter having counter states which condition power supply circuitry within the charger to the mode appropriate to the battery terminal voltage. The counter is conditioned to its deep discharge state by actuation of a user-accessible switch. When the terminal voltage falls below a first predetermined level, the counter automatically reverts from the discharge state to its fast charge state to establish the fast charge mode. When the terminal voltage rises above a second predetermined level, the counter automatically reverts to its trickle charge state to establish the trickle charge mode.

Abstract: A battery charger for supplying charging current to the rechargeable battery of a portable battery powered device includes a one-piece housing and removable bottom plate. A first portion of the housing includes a receptacle for receiving the device. Upon insertion of the device into the receptacle electric contacts projecting from the bottom wall of the receptacle are biased by a spring acting against the bottom plate into electrical contact with the device to establish electrical communication between the device and charging circuitry within the housing. A first portion of the circuitry is contained within the first portion of the housing to provide mode indications and switch means user-actuable through an aperture in the bottom wall of the receptacle. A second portion of the circuitry is contained within a second portion of the housing having integral ribs on its exterior surface for improved heat dissipation.

Abstract: A housing for an electronic circuit board includes a housing member and identical top and bottom cover members. Inwardly extending ribs located on the interior sidewalls of the housing member align and support the circuit board, and provide convection cooling channels which allow air to circulate freely over the circuit board. The housing member is preferably an integrally cast member formed with integral fin surfaces which dissipate heat for the protection of temperature sensitive electronic components within the housing.

Abstract: A swivel base assembly for mounting radio apparatus or the like on a supporting surface includes a first support element for engaging the apparatus housing and a second support element for engaging the supporting surface. A spacing element in the form of a sphere allows relative movement between the support elements while maintaining a fixed minimum spacing. Locking means in the form of interlocking hook members draw the mounting plates into engagement with the spacer element to fixedly position the first plate with respect to the second plate and the supporting surface.

Abstract: A battery charger system for supplying charging current to either a battery-powered transceiver or to the rechargeable battery pack of the transceiver includes a housing housing a receptacle for receiving the transceiver. Upon insertion of the transceiver into the receptacle an electric contact projecting from the bottom wall of the receptacle contacts the transceiver to establish electrical communication between the device and charging circuitry within the housing. When supplying charging current to the battery pack an adapter having a smaller receptacle is inserted into the receptacle to establish electrical communication between the contacts and the battery pack. A reciprocatively mounted actuator stem in the adapter housing enables actuation of a deep-discharge mode select switch through an aperture in the bottom wall of the receptacle.

Abstract: A housing for a battery operated portable transceiver includes an elongated generally rectangular housing. A battery pack received in a recess in the housing forms in part a surface for gripping the housing. A combined latch and contact arrangement retains the battery pack in position and establishes electrical contact between the battery pack and the transceiver. A protective boot fitted to the lower end of the housing protects the transceiver from physical shock.

Abstract: A belt holder for portable radio apparatus and the like includes a belt fastener and a receptacle housing. The receptacle housing is pivotally mounted to the belt fastener. A clamp mechanism includes a sliding clamp body having two projecting clamp arms which engage the radio apparatus to prevent the apparatus from falling from the receptacle housing. A cam mechanism, operated with rotation of the receptacle housing with respect to the belt fastener, actuates the clamp mechanism to disengage the radio apparatus from the belt holder.

Abstract: A method and apparatus for producing a honeycomb pattern of projecting frameworks from a drop ceiling utilizes cardboard rectangular frameworks having four side walls with respective hinged locking flaps along a top edge of the side walls. As the cardboard frameworks are inserted from below into rectangular support frames of the drop ceiling, the hinged locking flaps are pushed flush against outside surfaces of the framework side walls until they clear the support frames. After clearance is achieved, the locking flaps assume a locking position wherein they abut against a corner formed by T-section channels of the drop ceiling defining the support frames.