Abstract: A display test system includes a symbol source and a controller connected to the symbol source for receiving a symbol in response to a testing event whereupon the controller causes the display to produce a first area having a first light intensity, and the symbol at a second light intensity within the first area. A viewer uses an input device to verify to the controller the ability to discern the difference in light intensities of the symbol and the first area by describing or identifying the symbol.

Abstract: A method and apparatus for evaluating the degradation of a video display device. Single parameter test signals and patterns, generated either internally or externally to the video device, are displayed on the screen. A sensing device such as a CCD camera reads the screen and transmits the data to a processing unit. Codes, imbedded in the test signal or pattern, indicate to the testing device what test is currently being run, the content of the test, and/or the specific setup situation. The code may be inherent in the pattern, the sequencing, or in addition thereto. The processing unit reads and interprets the results in accordance with the received test codes. The apparatus includes a portable, hand-held unit capable of detecting video degradation on a pass/fail basis. The unit is separate from the display under test and is capable of identifying and evaluating the test through the receipt and interpretation of the embedded codes in the test patterns, and evaluating performance on a go/no-go basis.

Abstract: A method and apparatus for evaluating the degradation of a video display device. Single parameter test signals and patterns, generated either internally or externally to the video device, are displayed on the screen. A sensing device such as a CCD camera reads the screen and transmits the data to a processing unit. Codes, imbedded in the test signal or pattern, indicate to the testing device what test is currently being run, the content of the test, and/or the specific setup situation. The code may be inherent in the pattern, the sequencing, or in addition thereto. The processing unit reads and interprets the results in accordance with the received test codes. The apparatus includes a portable, hand-held unit capable of detecting video degradation on a pass/fail basis. The unit is separate from the display under test and is capable of identifying and evaluating the test through the receipt and interpretation of the embedded codes in the test patterns, and evaluating performance on a go/no-go basis.

Abstract: A control system for controlling a heating system having a heat pump and a source of supplemental heat. The indoor heat exchanger temperature is monitored, such as by a thermocouple or the like, and when the temperature falls below a given threshold level, defrost cycling of the heat pump is initiated. The control system monitors the defrost cycling of the heat pump, and when the heat pump is in its defrost cycle for more than a predetermined portion of a heating cycle, the heat pump will be shut down until the outdoor ambient temperature has risen by a predetermined amount or a given interval of time has elapsed.

Abstract: A control system for controlling a heating system having a heat pump and a source of supplemental heat. Simultaneous operation of the heat pump and supplemental heat source is monitored, and when such simultaneous operation occurs for a given portion of a heating cycle, the heat pump will shutdown until the temperature has risen by a predetermined amount or a given interval of time has elapsed. The heat pump is also shutdown if the outside ambient temperature falls below a certain level and is automatically reenabled if the outside ambient exceeds a second level.

Abstract: A control system for controlling a heating system having a heat pump and a source of supplemental heat. The control system monitors the defrost cycling of the heat pump, and when the heat pump is in its defrost cycle for more than a predetermined portion of a heating cycle, the heat pump will be shut down until the outdoor ambient temperature has risen by a predetermined amount or a given interval of time has elapsed. The heat pump is also shut down if the outside ambient temperature falls below a certain level and is automatically reenabled is the outside ambient exceeds a second level. The system results in more efficient operation of the heat pump/supplemental heat system by disabling the heat pump when weather conditions do not favor efficient heat pump operation.