COMPACT HANDS-FREE ADAPTER FOR USE WITH A CELLULAR TELEPHONE

摘要

The present invention provides a portable, pocket sized speakerphone device (102) adaptable for use with a cellular telephone (120), and a method (Fig. 1) for making such a device. The device reduces howling, including echoing and feedback, sufficiently to enable use of the device as a telephone speakerphone (102). To reduce howling, one or more of the following may be utilized: attenuation circuitry; sound insulation means; positioning the loudspeaker (116) and the microphone (114) of the device such that the outlet of the loudspeaker (116) for emitting sound from the loudspeaker (116) faces in the same direction as the outlet of the microphone (114) for receiving sound into the microphone (114) and such that a line extending between the outlet of the loudspeaker (116) and the outlet of the microphone (114) would form a right angle with a line extending in the direction of the outlet of the loudspeaker and the outlet of the microphone face.