Abstract: A headset control system for operating a microcontroller based device includes a microphone, a first and a second speaker, and a user operated switch. The switch selectively disables said first speaker in a first state or said microphone in a second state. A momentary switch creates patterns of momentary switching from one of a first, a second and a third state to at least one other state and back. A switch detector comprises a plurality of comparators to implement threshold logic and produces a signal indicating the respective states of said user-operated switch and said momentary switching means. A microcontroller responsive to said switch detector includes a means to differentiate between different switching patterns of said momentary switching means and initiates respective function as a function of a pattern of momentary switching and state of said user-operated switch and current operational mode.

Abstract: A constant wattage electronic ballast circuit for lamp comprises a circuit for producing a voltage feedback signal substantially proportional to voltage of the lamp. A diode function generator processes the voltage feedback signal so as to produce a processed signal which, within sequential bands of lamp voltage, varies less for a specified variation of lamp voltage in a higher voltage band than in a lower voltage band. A circuit produces a current feedback signal substantially proportional to current in the lamp. A circuit for controlling lamp current comprises a circuit for summing the processed signal with the current feedback signal to create a summed signal, and a circuit for adjusting lamp current in response to the difference between the summed signal and a reference signal.

Abstract: A portable communication and audio system includes a radio telephone for receiving a first audio signal and transmitting a corresponding first radio signal through a transmitter to another location, and for receiving a second radio signal through a receiver and converting it to a second audio signal. An audio device provides a third audio signal. A microphone receives the first audio signal. A headset with first and second speakers is provided for selectively listening to the second or the third audio signal. A user-operated switch selectively disables the first speaker in a first state or the microphone in a second state. A state-indicating apparatus produces a signal indicating the state of the user-operated switch.

Abstract: A network of identical atmospheric hazard detectors communicates a locally sensed hazard condition directly to multiple neighboring detectors using RF command communication, without the use of wires and without a central control location. Each detector includes a sensor of an atmospheric hazard, a detection circuit for measuring the sensor output and creating a local hazard signal, an alarm indicator, an RF transmitter for sending a neighboring hazard signal to the network, and an RF receiver for receiving a neighboring hazard signal from the network. The local alarm and neighboring alarm control signals produce discernibly different alarm indications from the detector's alarm device, facilitating an attempt to locate the origin of a hazard. In the preferred embodiment, every detector functions as a receive/transmit relay station, enabling the network to be extended in spatial expanse without limit and without increasing the power output of the RF transmitter.