Abstract: Electronic circuit and control system and method in hardware and software for controlling fuel cell and fuel cell powered electrical or electronic device. System, device, method and computer program and computer program product for monitoring and controlling fuel cell based power supply and powered information appliance, such as mobile telephone and laptop computer. Fuel cell for powering and fuel cell powered information appliance or computer. Fuel cell power pack adapted to provide electrical operating power to an electrical device. Interface circuit and control device and method for a fuel cell powered electronic device. Method of controlling operation of a fuel cell to generate electricity for an electrical device. Electrical control power pack adapted to replace battery for a laptop computer.

Abstract: A method and apparatus for continuously monitoring and measuring the concentration of gases in a gas-containing liquid such as a transformer oil. The method and apparatus employ a passive gas extraction technique which comprises a high performance membrane material to extract dissolved gases from the oil, and an IR-based sensor to detect gases present. The passive gas extractor extracts dissolved gas from the gas-containing liquid, there being a known relationship between the concentration of a constituent gas in the extracted gas and the concentration of the constituent gas remaining dissolved in the gas-containing liquid. The gas sensor senses the concentration of a constituent gas in the extracted gas, in the presence of other constituent gases.

Abstract: An apparatus (10) and a method are described for extracting gas from a liquid containing dissolved gas. The liquid is pumped from an external reservoir (40) of the liquid into a separation cell (14) by a liquid-pumping chamber (11). In separation cell (14) a permselective membrane (17) effects extraction of the dissolved gas from the liquid. A gas-pumping chamber (23) pumps the extracted gas from the permeate chamber (16) of the separation cell (14) to a collection station (27), where the extracted gas can be analyzed, separated into its individual components, or stored, as desired.

Abstract: A method for powering a system for transmitting and receiving multiple telephone transmission signals over a single twisted pair. The method also powers down a portion of the system. An analog signal from a local switching station is converted to an 80 kbits/sec signal for transmission over a twisted pair. A remote terminal converts the 80 kbits/sec signal back into a conventional analog signal for use in conventional telephone, facsimile or other related equipment.

Abstract: A test system directed to apparatus for transmitting and receiving multiple telephone transmission signals over a single twisted pair. The system converts an analog signal from a local switching station to an 80 ksymbols/sec signal for transmission over a twisted pair by a line card. A remote terminal converts the 80 ksymbols/sec signal back into a conventional analog signal for use in conventional telephone, facsimile or other related equipment. The test equipment separately tests the entire system, the line card portion of the system, the remote terminal portion of the system, and the twisted pair.

Abstract: A method and apparatus for transmitting and receiving multiple telephone transmission signals over a single twisted pair. An analog signal from a local switching station is converted to an 80 kbits/sec signal for transmission over a twisted pair. A remote terminal converts the 80 kbits/sec signal back into a conventional analog signal for use in conventional telephone, facsimile or other related equipment.

Abstract: A method and apparatus for transmitting and receiving multiple telephone transmission signals over a single twisted pair. An analog signal from a local switching station is converted to an 80 kbits/sec signal for transmission over a twisted pair. A remote terminal converts the 80 kbits/sec signal back into a conventional analog signal for use in conventional telephone, facsimile or other related equipment.

Abstract: A method and apparatus for transmitting and receiving multiple telephone transmission signals over a single twisted pair. An analog signal from a local switching station is converted to an 80 kbits/sec signal for transmission over a twisted pair. A remote terminal converts the 80 kbits/sec signal back into a conventional analog signal for use in conventional telephone, facsimile or other related equipment.

Abstract: A test system directed to apparatus for transmitting and receiving multiple telephone transmission signals over a single twisted pair. The system converts an analog signal from a local switching station to an 80 ksymbols/sec signal for transmission over a twisted pair by a line card. A remote terminal converts the 80 ksymbols/sec signal back into a conventional analog signal for use in conventional telephone, facsimile or other related equipment. The test equipment separately tests the entire system, the line card portion of the system, the remote terminal portion of the system, and the twisted pair.

Abstract: A test system directed to apparatus for transmitting and receiving multiple telephone transmission signals over a single twisted pair. The system converts an analog signal from a local switching station to an 80 ksymbols/sec signal for transmission over a twisted pair by a line card. A remote terminal converts the 80 ksymbols/sec signal back into a conventional analog signal for use in conventional telephone, facsimile or other related equipment. The test equipment separately tests the entire system, the line card portion of the system, the remote terminal portion of the system, and the twisted pair.

Abstract: A test system directed to apparatus for transmitting and receiving multiple telephone transmission signals over a single twisted pair. The system converts an analog signal from a local switching station to an 80 ksymbols/sec signal for transmission over a twisted pair by a line card. A remote terminal converts the 80 ksymbols/sec signal back into a conventional analog signal for use in conventional telephone, facsimile or other related equipment. The test equipment separately tests the entire system, the line card portion of the system, the remote terminal portion of the system, and the twisted pair.

Abstract: Apparatus and method for monitoring a self-regulating heater comprising a PTC conductive polymer while it is being powered by a power supply signal. The apparatus is connected to a power supply and to the heater, the heater then producing a heater signal which is fed to a comparator. The comparator deterines the phasal relationship between the power supply signal and the heater signal and indicates when the signals are out of phase by a predetermined magnitude.