Abstract: A signal processing method and apparatus provides a capability of storing a portion of an input signal representing a received program and accessing the stored information to provide a signal component representing a time-compressed version of the portion of the program during a playback mode of operation. When viewed, the time-compressed signal produced during playback provides the portion of the program in a fraction of the original time duration of the portion of the program. Playback occurs at a rate faster than the rate at which new data is stored and, as a result, there will be point in time at which the “past” signal produced during playback and the received signal, or original input video signal, coincide in time. This point in time is detected and the output signal is automatically switched back to the received program signal.

Abstract: A system for programming/controlling various audio/video devices coupled to one another via a bus structure, through the use of a single macro key utilizes an addressing structure. Each various audio/video device includes memory and a processor/controller for the memory and bus management. The memory is divided into master data memory and slave data memory depending on the role of the audio/video device. Data transfer over the bus only contains dummy numbers that are used as macro command addresses, with the macro data itself processed and stored in the various audio/video device. This eliminates the need to store the different commands of the various audio/video devices in the device chosen to initiate the macro. For each macro, one audio/video device is the master device while the remaining audio/video devices are slaves.

Abstract: A circuit presented automatically controls sound level. Sudden peak signal levels are controlled with a fast time constant of response and the overall sound level is controlled with a slower time constant of response. The feature can be enabled or disabled by the user via a microprocessor responsive to a remote control.

Abstract: A full wave rectified AC mains supply voltage is produced from an AC mains supply voltage without low-pass filtering. The rectified voltage is developed in a winding of a flyback transformer. The winding of the flyback transformer is also coupled to a switching transistor that generates in the winding a first plurality of current pulses at a frequency that is higher than the frequency of the mains supply voltage. The current pulses energize a load circuit. A capacitor voltage is coupled via a second switching transistor to the winding to produce in the winding a second plurality of current pulses that energize the load circuit during a portion of the period of the mains supply voltage that does not occur in the vicinity of the peak of the mains supply voltage. When the second plurality of current pulses are generated, the mains supply voltage is decoupled from the first winding.

Abstract: A pulse-width modulator controls a switching transistor. The switching transistor is coupled to a primary winding of a chopper transformer. The switching transistor and the primary winding are referenced to a nonisolated ground conductor. To initiate a standby mode of operation, a first on/off control signal that is referenced to an isolated ground conductor disables a horizontal oscillator that is energized from a secondary winding of the chopper transformer and that is also referenced to the isolated ground conductor. As a result, a decrease loading of circuit elements that are referenced to the isolated ground occurs. In the standby mode, current pulses in the primary winding are produced at a substantially higher frequency than in normal operation. A frequency detector referenced to the nonisolated ground generates a second on/off control signal that is referenced to the nonisolated ground in accordance with the frequency of the current pulses in the chopper transformer.

Abstract: In a switch mode power supply, a full wave rectified AC mains supply voltage is produced from an AC mains supply voltage without low-pass filtering. The unfiltered rectified voltage is applied to a winding of a flyback transformer that is coupled to a switching transistor. A first plurality of current pulses are generated in the winding from the rectified voltage at a frequency that is higher than the frequency of the mains supply voltage and at peak amplitudes that vary in accordance with the rectified voltage in a manner to increase a power factor. The rectified voltage is further rectified via a rectifier coupled in series with a resistor and a low-pass filter capacitor and produces current pulses in the capacitor. A voltage in the capacitor is coupled via a second switching transistor to the winding to produce in the winding a second plurality of current pulses that reduce a ripple component at an output of the power supply.

Abstract: In a switch mode power supply, a full wave rectified AC mains supply voltage is produced from an AC mains supply voltage without low-pass filtering. The unfiltered rectified voltage is applied to a winding of a flyback transformer that is coupled to a switching transistor. A first plurality of current pulses are generated in the winding from the rectified voltage at a frequency that is higher than the frequency of the mains supply voltage and at peak amplitudes that vary in a manner to reduce a power factor. A second supply voltage is applied via a second switching transistor to the winding to produce in the winding a second plurality of current pulses that reduce a ripple component at an output of the power supply. The second plurality of current pulses are pulse-width modulated in a feed-forward manner during a period of the mains supply voltage in accordance with the mains supply voltage.