Abstract: In an exit sign, a canopy bracket has a pair of resilient spring fingers which are inserted through a central circular opening of a mounting plate mounted to a standard electrical box located in a wall or ceiling. The spring fingers temporarily secure the canopy bracket to the mounting plate thus allowing an electrician to easily align and secure screws to the mounting plate, thereby greatly facilitating installation. The wires from the electrical box are extended through mounting plate and the canopy prior to securing the canopy to the mounting plate. Once secured, the user simply fits a hub portion of the canopy bracket telescopically within an opening with the exit sign housing. Spring capture barb members of the hub engage the housing to fixedly secure the exit sign to the wall or ceiling. Then the user connects the wires extending from the canopy bracket to those in the exit sign.

Abstract: In an exit sign, a canopy bracket has a pair of resilient spring fingers which are inserted through a central circular opening of a mounting plate mounted to a standard electrical box located in a wall or ceiling. The spring fingers temporarily secure the canopy bracket to the mounting plate thus allowing an electrician to easily align and secure screws to the mounting plate, thereby greatly facilitating installation. The wires from the electrical box are extended through mounting plate and the canopy prior to securing the canopy to the mounting plate. Once secured, the user simply fits a hub portion of the canopy bracket telescopically within an opening with the exit sign housing. Spring capture barb members of the hub engage the housing to fixedly secure the exit sign to the wall or ceiling. Then the user connects the wires extending from the canopy bracket to those in the exit sign.

Abstract: An improved power supply capable of driving an external device at relatively high power levels for intermittent periods of time with the power supply driven by relatively low current input power which can vary widely in voltage. The power supply incorporates a step-up switching voltage converter module for increasing the input voltage to a higher value so as to charge an energy storage capacitor to an energy level sufficient to power the external device for said intermittent periods of time at relatively high current. The energy storage device voltage output is regulated by a step-down switching voltage converter module. Control signals sensing the voltage of the energy storage capacitor can be used to control energization and de-energization of the external device.

Abstract: A communication method and system for determining the transmission speed of a communicating remote unit with respect to a host communicator. The communication method uses a start of message header containing a known number of timing intervals, called ticks, with the header transmission in a logic one or a logic zero state. A start of message header is detected by the host communicator and its logic one state is sampled after a given period of time in order to determine its actual logic one duration. From this, the actual tick time is determined so as to be able to determine data "1" bits and data "0" bits from the remote unit by sampling the incoming data at precise intervals of time so as to properly determine the data bit states. A logic zero to logic one state transition at the start of each data bit is used to reset the communicator tick timer.

Abstract: An improved line receiver with high common mode rejection is operable at voltages above the power supply voltage (VCC) as well as below ground. Input resistors provide high input impedence as well as means through which current summing of current mirror currents at the input transistor base nodes is translated into voltage drops which boosts the common mode rejection range of the circuit. Built-in hysteresis circuitry ensures proper detection of non-common mode signals. The high input impedence and high sensitivity allow multiple receivers of the type to be connected in parallel across a common bus for interrogation by a remote system. The preferred embodiment of the present invention is implemented in integrated circuit technology.