Motorola Corporation

Bakulesh B Patel

David H Karl

Bruce W Staple

Jaromir R Bares

James H Stangel

Rebecca C McNally

A packaging scheme (10) for a microphone (22) comprises a housing having first opening (50) and a second opening (52) at opposing ends of the housing. The microphone has a top portion and a bottom portion arranged within the housing wherein the top portion is exposed to the first opening and the bottom portion is exposed to the second opening. Finally, a porous membrane (20) is mounted between the microphone and the openings on the opposing ends of the housing. The porous membrane can be retained against the housing using a sticker (16).

Microphone packaging scheme

An apparatus for mounting a noise cancelling microphone (34) within a communication device comprises a housing having a front portion (36), a back portion and side portions (40). The front portion (36) and one of the side portions (40) have apertures (38 and 40). Within the housing lies a receptacle (32 or 50 or 100) for retaining a microphone or transducer (34). The receptacle is arranged and constructed to form a chamber (32) between the apertures (38 and 40) in the front portion (36) and the side portion (40) of the housing.

Noise cancelling microphone and boot mounting arrangement

A speaker grille assembly (800) includes a speaker grille 410), a felt (200), and a speaker (300). The speaker grille has a front surface (420), and a rear surface (430). The speaker grille (410) has plurality of equally spaced channels (440) for passage of sound. The sound channels (440) are formed such that that the rear surface port (422) is substantially larger than front surface port (411) thereby enhancing acoustic power transfer by increasing the effective sound passage space. The sound channels (440) can be formed such that the passage through the grille (410) are provided with either gradual or sudden transition from front port (411) to the rear port (422) resulting in a larger rear surface apertures.

Speaker grille assembly

A speech amplifier circuit increases the maximum perceived loudness at the speaker (412) and reduces distortion at high volume levels without increasing the power consumed by the speech powder amplifier (410). When a low volume is selected by the volume control (414), the microcomputer (418) sets the step attenuator (406) at a correspondingly high attenuation level and the high-pass filter (408) is bypassed. As the volume control (414) is advanced and the speech power amplifier (410) is 12 dB into clipping, the microcomputer (418) activates the high-pass filter (408) and simultaneously steps the gain of the step attenuator (406) by 6 dB.

Radio receiver speech amplifier circuit

A microphone mounting arrangement for altering the microphone's audio frequency response characteristic comprises a microphone disposed within an enclosure bounded by a loudspeakers cone on one side and a flexible diaphragm on the other side. The microphone is preferably mounted to a web-like mounting structure which is sandwiched between the loudspeaker and the flexible diaphragm. The resonant characteristic of the enclosure selectively alters the intensity of soundwaves impinging upon the diaphragm so that enclosed microphone's frequency response is altered. Improved intelligibility in high noise level environment is thereby attained.

Growing community of inventors

Coral Springs, FL, United States of America

Bakulesh B Patel