Abstract: A battery charger for a hearing aid includes a housing that defines at least one socket for receiving any one of a plurality of adapters. Each adapter closely fits and at least partially contains one hearing aid to hold the hearing aid in place during charging. The hearing aid includes a plurality of electrical contacts in a pattern and the adapter defines a plurality of apertures in the same pattern. Resilient contacts in the charger extend through the apertures in the adapter to contact the hearing aid.

Abstract: An audio signal is divided among exponentially related subband filters. The spectral flatness measure in each subband signal is determined and the measures are weighted and combined. The sum is compared with a threshold to determine the presence of music or noise. If music is detected, the noise estimation process in the noise reduction circuitry is turned off to avoid distorting the signal. If music is detected, residual echo suppression circuitry is also turned off to avoid inserting comfort noise.

Abstract: Feedback detection, adaptive notch filtering, and gain adjustment are combined for managing feedback. Feedback detection includes detection of short term and long term spectral peaks and assessing their magnitude, shape, rate of growth, and power concentration ratio. A plurality of notch filters are available and are allocated according to the spectral magnitude of the feedback detected. Wide band gain adjustment supplements the notch filters.

Abstract: A hearing aid is identified by storing a binary code in the hearing aid, receiving a transmitted code, reading out a subset of bits from the stored binary code, and comparing the transmitted code with the subset for identification. The reading step preferably reads the lowest order nibble, byte, or word of the binary code. In accordance with another aspect of the invention, a charger for the hearing aid, a controller for the hearing aid, and a programmer for the hearing aid store the identification codes for two way communication among the devices.

Abstract: A light shutter includes a first electrode, a second electrode, and a third electrode, wherein the first and second electrodes are capacitively coupled to each other by the third electrode. The first electrode and the second electrode can be segmented and the segments separately addressed. In a display having a light shutter and an EL panel stacked on the same side of a substrate, there is a common front electrode and separate rear electrodes for operating the light shutter and the EL panel. The common electrode is electrically floating and the rear electrodes are capacitively coupled to each other by the common front electrode. The rear electrodes can be segmented and the segments separately addressed.

Abstract: A power supply for driving an EL panel includes an inverter that produces a polarity reversing voltage at a pair of output terminals. A switching circuit coupled to the output terminals and to at least one EL lamp applies alternating current to the at least one EL lamp in the on state and blocks current from the EL lamp in the off state. The switching circuit includes a first bidirectional switch connecting a first terminal of the EL lamp to a first output terminal and a second bidirectional switch connecting a second terminal of the EL lamp to a second output terminal.

Abstract: A two step etch is used to provide access to the front electrode of an EL panel cut from a larger EL panel. The two step etch produces a set back that electrically isolates the front electrode and enables a conductive layer to be easily deposited on the front electrode. A kit contains the necessary materials and instructions for practicing the method.

Abstract: A hearing aid is identified by storing a first binary code in the hearing aid as a first identification code, storing a second binary code in the hearing aid as a default code, and replacing the default code with a second identification code if a second hearing aid is used by the person using the first hearing aid. The identification code includes a bit indicating for which ear the hearing aid is intended. If two hearing aids are used, the identification code of the first hearing aid is substituted for the default code in the second hearing aid and vice-versa, thereby pairing the first hearing aid with the second hearing aid and indicating that there are two hearing aids needed, even if one hearing aid should become lost or inoperative.

Abstract: A display includes a light switch overlying a backlight and having at least two light shutters which do not, by themselves, convey information by the shape thereof. The lit area of the backlight is equal to or greater than the sum of the areas of the shutters within the area. The display can also include a graphics layer overlying the light switch. The information content of the display is changed by changing the graphics layer.

Abstract: An antenna includes an element that is made by thermally bonding a patterned conductive layer to a dielectric sheet. The antenna can be redesigned easily for prototype or low volume production yet the invention is suitable for volume production as well. The antenna, or an element thereof, can be made from a xerographic print using toner as an adhesive.

Abstract: A control module operates a ramp in coordination with a powered sliding door. The control module couples to the OEM network and includes at least one microprocessor, a connector array coupled to at least one microprocessor, and interface circuitry. The microprocessor produces data sequences to keep the network busy, thereby preventing other modules on the OEM network from entering a low power mode. The connector array is adapted to receive daughter boards, plugs, plug-in modules, or wire jumpers for patches. The control module includes a display and a microprocessor is programmed to diagnose the operation of the ramp and provide the results of the diagnosis on the display.

Abstract: A background noise estimate based upon a modified Doblinger noise estimate is used for modulating the output of a pseudo-random phase spectrum generator to produce the comfort noise. The circuit for estimating noise includes a smoothing filter having a slower time constant for updating the noise estimate during noise than during speech. Comfort noise is smoothly inserted by basing the amount of comfort noise on the amount of noise suppression. A discrete inverse Fourier transform converts the comfort noise back to the time domain and overlapping windows eliminate artifacts that may have been produced during processing.

Abstract: A programmed microprocessor has a learning mode of operation wherein data to and from a circuit coupled to a wiring harness in a vehicle is stored by the microprocessor. After the learning mode is completed, removal of the circuit does not cause an error condition because appropriate data is supplied instead by the microprocessor. A sleep mode of operation prevents the microprocessor from interfering with the operation of the circuit when the circuit and the microprocessor are coupled to the wiring harness.

Abstract: A hearing aid having a rechargeable battery and a charger for charging the battery includes a first microphone and a first speaker in the hearing aid and a second microphone and a second speaker in the charger for acoustically transferring data between the hearing aid and the charger. The hearing aid can detect the charge state of a battery and send a signal to the charger indicative of the charge state. The charger also includes a chamber for receiving at least a portion of the hearing aid.

Abstract: Comfort noise is derived from a white noise signal by filtering the white noise signal in a QMF bank to produce comfort noise signal that is selectively coupled to at least one channel in a telephone. Preferably, a plurality of QMF banks are used and the magnitude of the white noise into each filter is controlled in accordance with the magnitude of the signal in a corresponding analysis sub-band in a channel. In accordance with another aspect of the invention, the signals from higher frequency analysis sub-bands are combined and control a single input to a QMF bank, thereby increasing the low frequency resolution of the comfort noise. In accordance with another aspect of the invention, the QMF banks are cascaded upwardly (the output of one bank is coupled to the low pass input of the next bank), which also enhances the low frequency resolution of the comfort noise.

Abstract: A path change is detected by multiplying the energy of a signal on the output of a summation circuit in one channel of a telephone by a constant to produce a product. The product is compared with the energy of a signal on the input of the summation circuit. A path change is indicated when the energy of the product exceeds the energy of a signal on the input of the summation circuit. The comparison is made in successive frames of an audio signal and a path change is indicated when the energy of a signal on the input of the summation circuit is exceeded in two or more successive frames.

Abstract: The unlit margin of a first EL lamp is covered by the lit edge of a second EL lamp to provide a substantially seamless lit area. The lamps are joined mechanically. The EL lamps are connected in parallel electrically by conductive tape overlying at least a portion of the bus bars of the lamps. A plurality of lamps can be joined together to provide an EL lamp substantially larger than obtainable by other means.

Abstract: In a noise suppresser, an input signal is converted to frequency domain by discrete Fourier analysis and divided into Bark bands. Noise is estimated for each band. The circuit for estimating noise includes a smoothing filter having a slower time constant for updating the noise estimate during noise than during speech. The noise suppresser further includes a circuit to adjust a noise suppression factor inversely proportional to the signal to noise ratio of each frame of the input signal. A noise estimate is subtracted from the signal in each band. A discrete inverse Fourier transform converts the signals back to the time domain and overlapping and combined windows eliminate artifacts that may have been produced during processing.

Abstract: A combination of noise suppression using a Bark band modified Weiner filter and linear noise reduction improves elimination of noise in a telephone. A detector for detecting long, non-speech intervals is coupled to the output of the noise suppresser and controls selection of noise suppression or noise reduction. A gain smoothing filter has a long time constant when noise reduction is used and provides a gradual transition from one level of gain to another. Comfort noise is smoothly inserted by updating the data for generating comfort noise only during detected long, non-speech intervals.

Abstract: An EL panel on a rigid substrate is thinned in selected areas, or overall, to provide a backlight for keypads and other applications that would otherwise require a more flexible panel or additional structure. Lamp materials are deposited on one side of a rigid substrate and then substrate material is ablated with a suitable tool, working from the opposite side of the substrate as the lamp materials. The depth of cut can be constant or variable, enabling one to tailor the flexibility of an area to the desired tactile response for a keypad or to provide clearance in close quarters. The invention is compatible with known process for making an EL panel.