Abstract: The transducer diaphragm includes a folded sheet of thin film material, having printed circuit conductors formed thereon in a Greek or serpentine pattern. The Greek pattern includes an odd number of spaced, parallel, printed conductor lines formed into longitudinal and transverse groups, with return conductors extending around the perimeter of the pattern to complete loops of a voice coil. The sheet is folded to form a plurality of rearwardly extending projections, with the folding being along the center lines of each of the longitudinal groups. In the preferred form of the invention, each one of the projections is generally channel-shaped throughout its length, and has a bight portion interconnecting a pair of leg portions, with a longitudinal conductor in the center of the bight and other conductors in the longitudinal group opposite each other on the leg portions.

Abstract: An automatic gain control circuit for an output signal of a magnetic earpiece of a hearing aid, which comprises a voltage source, an output amplifier stage having an input connected to the voltage source and an output connected to the magnetic earpiece, the earpiece having a working winding connected between the amplifier stage output and the voltage source, and a control loop for automatic gain control. The control loop includes a rectifier and an additional winding connected in series with the working winding of the earpiece, the windings constituting an autotransformer, the additional winding connecting the rectifier to the output of the amplifier stage and the rectifier being connected to the input of the amplifier stage.

Abstract: A sound-wave receiving applicance comprises a resonance panel and a crystal type piezoelectric microphone responsive to oscillations generated by the soundwaves, said microphone being adapted for connection to an amplifier. The crystal of the microphone is subjected, between two pole members, to a mechanical initial pressure to increase the pressure sensitivity of the microphone relative to the resonance panel. The receiving applicance preferably has means for manual adjustment of the initial pressure which is absorbed by the resonance panel via one pole member. The resonance panel of the receiving appliance preferably is made of a material, such as a cellular plastic, having a higher porosity and a lower specific gravity than ordinary wood.

Abstract: A lock-releasing apparatus for use in a telepone set, having a lock-releasing button (61) for a locking mechanism which locks a handset (41) stationarily to a cradle (42). The lock releasing button also actuates a muting switch (71).

Abstract: A telephone line demarcation unit separates the telephone company's property and wiring from those of the user and provides security for the telephone line connections and connectors. Compartments in the unit provide easy access for the user and further provides a selection of different types of connections or equipment that can be utilized. The telephone company terminals and test boards are separately compartmented so that the compartments can be separately sealed with seals to discourage tampering and provide evidence of tampering, and yet the user's portion of the interface box demarcation unit can be easily accessed for connecting a variety of telephone equipment.

Abstract: A recreational cooler and speaker system includes an audio signal input terminal, such as an audio jack, on an outer wall of the cooler for driving speaker elements mounted to the cooler enclosure through an electrical path within the enclosure walls.

Abstract: An electroacoustic converter with a closed-off resonance chamber, e.g. a microphone, including frame (1) carrying an electrode (2) and a diaphragm (3) connected by a connecting member (5) to an amplifier. A band (17) of plastically deformable material is sealingly attached to the frame via a weld joint (15) for providing good bass reproduction. The sensitivity of the microphone, which depends on the volume of the resonance chamber, is adjusted to the desired value by forming a depression (16) in the band. In production, the frames (1) are attached to the band (17) and are conveyed thereby between different operation stations. Sensitivity is measured by a measuring apparatus (20) and a loudspeaker (18) and is adjusted by a tool (19).

Abstract: A telephone handset having a receiver housing at one end has a flux coil positioned at the front corner at the junction between the peripheral wall and the front wall of the housing. The flux coil is connected in series or in parallel with the receiver. The flux coil, by this arrangement, is positioned very close to the front face of the receiver housing, giving very good coupling between flux coil and a hearing aid. Normally unused space is occupied by the flux coil and permits use of any convenient receiver.

Abstract: An ear microphone includes a bimorph piezoelectric transducer mounted on a PC board having an amplifier therein and surrounded by a helically wound spring. The piezoelectric transducer and spring are potted in a semi-soft potting compound which is formed in a shape adapted to be inserted into an external auditory ear canal to permit bone conduction to the microphone element. A cable is coupled to the amplifier through which a signal can be withdrawn for processing by electronic equipment.

Abstract: A microphone apparatus includes an array of equally spaced microphones divided into a center subarray and a pair of side subarrays located one on each side of the center subarray. A first weighting network having a plurality of weighting factors impresses a first weighting function on signals from the center subarray. Second and third weighting networks each having a plurality of weighting factors impress second and third weighting functions respectively on signals from the side subarrays. The first, second and third weighting functions correspond respectively to center and side portions of a total function. Signals from the first weighting network are summed in a first adder, signals from the second and third weighting networks being summed in a second adder and cmbined with the output of the first adder in a third adder to produce an output signal.

Abstract: A directional microphone having an acoustic damping washer positioned about the microphone cartridge adjacent the microphone rear sound entry.

Abstract: A hearing aid having a microphone, an amplifier and a receiver for delivering the amplified sound to a user's ear, in which an adjustable resonant peak control is used to shift the frequency response of the amplifier to a lower frequency range in order to reduce feedback without substantial reduction in high frequency amplification or saturation levels.

Abstract: An improved headset of the type including a headband having two ends provided with sliding portions, wherein a pair of adjusting pieces are slidably received through the sliding portions to permit adjusting the height of the adjusting pieces with respect to the headband. The lower end of each adjusting piece is provided with a seat having a connecting member formed on the bottom thereof. A pair of main bodies, each body including a speaker and an ear cushion, are pivotally connected to the connecting members of the adjusting pieces so as to permit the main bodies to be rotated about the longitudinal axis of the headband.

Abstract: A hearing aid having a microphone (10), a microcomputer (12) for digital signal processing of digitized microphone signals and an electroacoustic converter (14) for acoustic reproduction of the processed digitized signals, is equipped with at least one further sensor (16, 18) responsive to signals outside the acoustical range of audibility. These further sensor signals are processed according to a different program stored in a second memory (19) and supplied as additional data via an output (B2) of the microcomputer (12) preferably to the electro-acoustical converter (14). As a result, data such as the signals of a traffic light transmitter, signals from a paging system, or signals announcing a telephone call, door bell or the like, can be superimposed on the normal auditory functions. By appropriately coordinate signal trains, for example generated in accordance with the program stored in the second memory, a hearing-impaired person can easily distinguish among these additional functions.

Abstract: An arrangement for releasably retaining a telephone apparatus in a standby condition includes a handset including an earpiece and a base having a shelf portion for receiving the earpiece. A hooking post member protrudes through the shelf portion and includes an integral spring to enable the hooking post member to be resiliently movable towards and away from the shelf portion. A switch hook which is separate from the hooking post is arranged to be actuated by the earpiece when the earpiece is brought into engagement with the base. When the earpiece engages the base shelf portion, the hooking post member is resiliently urged into contact with the earpiece for releasably retaining the earpiece on the base. A guide on the base prevents the hooking post member from twisting or rotating.

Abstract: An amphibious personal audio system is provided. The system includes a band for encircling a person's end. An audio device is secured to the band for generating an audio signal. The audio device is hermetically sealed. Speakers are electrically coupled to the audio device for converting the audio signal to an audio sound. The speakers and the electrical coupling are hermetically sealed. Earpiece assemblies are acoustically coupled to the speakers for transmitting the sound to a person's ears. The earpiece assemblies have an opening for transmission of sound to the user's ear canal, the earpiece assembly being adapted to substantially hermetically seal the user's ear canal around the opening.

Abstract: A hearing aid has a housing insertable into the auditory canal, wherein the housing contains at least a microphone, an amplifier, an earpiece and a power source. In instruments of this kind it has turned out to be desirable to have, in addition to the usual volume control, an additional control for varying the way the incoming sound signals are influenced by the amplifier (i.e. its characteristic) to adapt to individual hearing impairments. For this purpose the hearing aid provides in the housing space for the battery a pitch control in such a manner that its actuating member can be operated at least when the power source is removed from the instrument. This makes it possible to reduce the space requirement for the pitch control so that even hearing aids insertable into the auditory canal can contain such an additional control.

Abstract: In a hearing aid of the type having an electrical amplifier, wherein the improvement provides an audio signal processing circuit incorporated into the amplifier and including integral computing circuitry for controlling the operation thereof; the processing circuit providing circuitry for receiving an audio frequency electrical signal, circuitry for separating the audio frequency signal into a plurality of frequency bandwidths, circuitry for separately amplifying any audio frequency signal present in each of the bandwidths, circuitry for summing the amplified audio frequency signals from each of the bandwidths to produce a reconstituted signal, and circuitry for controlling amplification including circuitry for sampling any audio frequency signal present in each of the bandwidths and circuitry for determining, in response to the audio frequency signals sampled from all of the bandwidths the amplification level for each bandwidth for the separate amplification.

Abstract: The moving coil loudspeaker drive-unit comprises a voice coil (4) wound on a former (3) and having fixed thereto a diaphragm (6) and a rear suspension spider (5). The drive unit of the invention comprises a component part build-ring (7) incorporated with the voice coil former (3) and adapted to interconnect the rear suspension spider (5) with the coil former (3) and to accurately locate it with respect to the voice coil (4). The build-ring (7) is also adapted to connect the diaphragm (6) to the coil former (3) together with the dust dome (8). The build-ring (7) also includes projections (9) to accommodate the electrical voice coil termination arrangements (10).

Abstract: This microphone includes a microphone element, speaker and antenna all internal to the microphone housing. These components are carried by a chassis that is fastened to the microphone body at its lower end which also provides the effective attachment point for the microphone cable. The speaker is mounted in the chassis at an angle having its face slight upwardly incline to project sound towards the top of the microphone. An antenna element includes walls on either side of the speaker for reflecting sound upwardly. The antenna element has apertures in its top portion to allow for the passage of sound therethrough. The microphone element is also in a position for picking up sound through the top of the microphone.