Abstract: A ported electroacoustical device uses the action of the port to provide cooling airflow across a heat producing device. The device includes a loudspeaker enclosure including a first acoustic port, and an acoustic driver, mounted in the loudspeaker enclosure. The device also includes a heat producing device. The acoustic driver and the acoustic port are constructed and arranged to coact to provide a cooling, substantially unidirectional airflow across the heat producing device, thereby transferring heat from the heat producing device.

Abstract: A ported electroacoustical device uses the action of the port to provide cooling airflow across a heat producing device. The device includes a loudspeaker enclosure including a first acoustic port, and an acoustic driver, mounted in the loudspeaker enclosure. The device also includes a heat producing device. The acoustic driver and the acoustic port are constructed and arranged to coact to provide a cooling, substantially unidirectional airflow across the heat producing device, thereby transferring heat from the heat producing device.

Abstract: A surround for supporting a diaphragm used to create acoustic waves includes a rib section extending away from the diaphragm and a membrane section that is supported by the rib section. The membrane section has a thickness in a direction substantially normal to opposing top and bottom surfaces of the membrane section which is substantially thinner than a thickness of the rib section in a direction substantially normal to opposing top and bottom surfaces of the rib section. A restoring force returning the diaphragm to a home position is contributed to more due to deformation of the rib section than to deformation of the membrane section.

Abstract: An apparatus includes a housing. A waveguide is located within the housing. The waveguide includes a first subsection that bends around a first axis and has a first cross-sectional area with an aspect ratio that is substantially different from unity. A second subsection bends around a second axis that is non-parallel to the first axis and includes a second cross-sectional area with an aspect ratio that is substantially different from unity. A third subsection acoustically couples the first subsection to the second subsection. The third subsection includes a third cross-sectional area with an aspect ration that varies between the first aspect ratio and the second aspect ratio.

Abstract: An AM radio antenna circuit having a ferrite bar loop antenna comprises a resonating structure forming a balanced antenna circuit, a varactor diode tuning structure presenting a controllable capacitance to said winding structure, a DC path including the winding structure coupled to the varactor constructed and arranged to deliver a tuning signal to the varactor, and means for connecting the antenna circuit to the input of an external detector integrated circuit.

Abstract: An AM radio antenna circuit having a ferrite bar loop antenna comprises a resonating structure forming a balanced antenna circuit, a varactor diode tuning structure presenting a controllable capacitance to said winding structure, a DC path including the winding structure coupled to the varactor constructed and arranged to deliver a tuning signal to the varactor, and means for connecting the antenna circuit to the input of an external detector integrated circuit.

Abstract: A noise reducing AM receiver has a receiving stage for receiving an AM signal of carrier frequency separated from that in an adjacent channel by a predetermined spacing and that may have a noise component. A detecting stage is coupled to the receiving stage for detecting at least a first portion of the received AM signal. A filter is coupled to the detecting stage for extracting a spectral component from at least a first portion of the received AM signal. A noise detector is coupled to the filter for detecting the presence of a predetermined amount of noise in the spectral component and for providing a blanking control signal in the presence of at least the predetermined amount of noise. A first noise blanker is responsive to the blanking control signal to process at least one portion of the received signal in response to the control signal to reduce the audibility of the noise component.