Abstract: A personal microphone that includes a structure having a live-performance form factor, a capsule that converts acoustic energy into an input signal, a signal processor that converts the input signal into a processed output signal, and a microphone output connector. The signal processor has input terminals that receive the input signal and input/output terminals that receive a phantom DC voltage from the microphone output connector while sending the microphone output connector a processed output signal. The signal processor has a dynamic range compressor that compresses the processed output signal, and a programming or adjustment device that sets the signal processor operating parameters. The personal microphone can have a security device for avoiding unwanted changes to the operating parameters of the adjustable signal processor. The personal microphone can be powered by a phantom power supply coupled to the microphone output connector via a mixing console and/or other devices.

Abstract: An audio level compressor for compressing the dynamic range of an input audio signal. The audio level compressor can be part of a microphone, or a separate component. The audio level compressor includes input terminals for receiving the input audio signal, a lamp having a filament resistance that is a function of the input audio signal; a load resistance; a signal gain controller that includes a means for increasing dynamic range compression of the input audio signal, and output terminals for providing an output audio signal that is a function of the input audio signal and the signal gain. The signal gain controller provides a signal gain that is a function of the filament resistance and the load resistance. The audio level compressor can also include an expander circuit or a power conditioning circuit. Power can be provided by an internal source or a phantom power supply.

Abstract: A personal microphone that includes a structure having a live-performance form factor, a capsule that converts acoustic energy into an input signal, a signal processor that converts the input signal into a processed output signal, and a microphone output connector. The signal processor has input terminals that receive the input signal and input/output terminals that receive a phantom DC voltage from the microphone output connector while sending the microphone output connector a processed output signal. The signal processor has a dynamic range compressor that compresses the processed output signal, and a programming or adjustment device that sets the signal processor operating parameters. The personal microphone can have a security device for avoiding unwanted changes to the operating parameters of the adjustable signal processor. The personal microphone can be powered by a phantom power supply coupled to the microphone output connector via a mixing console and/or other devices.

Abstract: An audio level compressor for compressing the dynamic range of an input audio signal. The audio level compressor can be part of a microphone, or a separate component. The audio level compressor includes input terminals for receiving the input audio signal, a lamp having a filament resistance that is a function of the input audio signal; a load resistance; a signal gain controller that includes a means for increasing dynamic range compression of the input audio signal, and output terminals for providing an output audio signal that is a function of the input audio signal and the signal gain. The signal gain controller provides a signal gain that is a function of the filament resistance and the load resistance. The audio level compressor can also include an expander circuit or a power conditioning circuit. Power can be provided by an internal source or a phantom power supply.

Abstract: The invention relates to the provision of a sustainer that is compatible with single coil pickups and stacked, single coil pickups. In this regard, feedback is substantially eliminated by processing and altering the direct electromagnetic radiation emitted by the driver. Another aspect of the invention provides a musical instrument, and a sustainer for a musical instrument that overcomes the problems with shifting forces between magnetic fields that are present in some known prior art devices and that are worsened when the driver is placed between the neck pickup and the bridge pickup. Another aspect of the invention is to provide suitable drive force and battery life with half as many batteries of some known sustainers, thereby providing a high efficiency switching amplifier. Another aspect of the invention provides that the sustainer can be enabled or disabled by one momentary contact switch, thereby providing that the major components of the sustainer are responsive to a transition in a control signal.

Abstract: A sustaining device is provided for prolonging the vibration of a string of a stringed musical instrument having a first magnetic pickup means responsive to the vibration of the string. The sustaining device includes a magnetic string driver capable of inducing a vibration in the string. A first amplifier amplifies the output of the pickup to a level that provides sufficient energy to the driver to prolong the vibration of the string. A switch is coupled to the driver for selecting the mode of operation of the driver between the pickup mode of operation wherein the driver functions as a second magnetic pickup, and a driver mode of operation wherein the driver functions as a magnetic string driver. An output changing device is provided that is responsive to the switch for changing the output of at least one of the first pickup and a driver in response to a change in the mode of operation of the driver.

Abstract: A sustaining device is disclosed for prolonging the vibration of a string of a stringed musical instrument, such as an electrical guitar having a magnetic pickup responsive to a change in the magnetic field caused by vibration of the string. The sustaining device includes the magnetic string driver disposed in magnetic proximity to the pickup. an amplifier is coupled between the pickup and the driver for amplifying current from the pickup to the driver to impart sufficient magnetic drive energy to the driver to produce sustained vibration of the string. An unbalancing device is provided for creating a magnetic imbalance between the pickup and the driver to minimize direct magnetic feedback between the pickup and the driver. This unbalancing device can take the form of an unbalanced pickup, an unbalanced driver, or a shunt plate disposed between the pickup and the driver.

Abstract: A transducer for a musical instrument through which vibrations can be fed back to the instrument so that notes played on the instrument can be sustained. The transducer comprises a bracket for mounting the transducer to the instrument. First and second opposited permanent magnetic poles project away from the bracket. A first surface of a sheet of non-magnetic, non-electromagnetic resilient material is attached to the projecting first and second magnetic poles. An electromagnetic core has a spine and first and second legs originating at, and extending away from, the spine and terminating at first and second end faces, respectively. The first and second end faces are attached to a surface of the sheet opposite the surface of the sheet to which the permanent magnetic poles are attached, with the first face adjacent the first permanent magnetic pole and the second face adjacent the second permanent magnetic pole. A conductor is wound on the core.

Abstract: A low pass filter is placed between an input pre-driver amplifier and an output driver amplifier of a display driver stage, e.g., forming a cascode amplifier. The filter suppresses noise components present in the signal from the pre-driver to prevent the noise components from being amplified and radiated by the output driver amplifier. The filter also suppresses high frequency arc currents before reaching the pre-driver amplifier.

Abstract: Apparatus to permit service adjustment of a television receiver includes a microprocessor which normally controls parameters of a video signal processed by the receiver. The microprocessor also automatically establishes a desired video signal reference condition for the service mode when manual service controls are to be adjusted. The service mode is entered by pressing a designated microprocessor keyboard key while plugging the receiver into a source of primary AC power.

Abstract: An auxiliary kinescope beam current limiter in a television receiver includes a control circuit responsive to a sensed signal representative of the combined instantaneous magnitudes of plural color video signals. The control circuit includes, in the order named, a first low pass filter, a first peak detector, a second low pass filter, and a second peak detector which provides a control signal to video signal processing circuits for limiting the amplitudes of the plural color video signals when a given amplitude threshold value is sensed as having been exceeded. The auxiliary beam current limiter is able to prevent warping or blistering of a shadow mask in a color kinescope due to scenes having a high beam current in, for example, an area equal to or greater than five to ten percent of the display screen area of the kinescope in both the horizontal and vertical directions.