Abstract: A method of acoustic transducer calibration (200, 400) using a band limited pseudo random noise source with an internal digital signal processor (209, 403) to tailor audio characteristics of an internal microphone 103 and internal speaker (301) within a communications device (101) to insure consistent amplitude and frequency characteristics of these microphone and speaker transducer devices. The method offers and advantage such that tuning of the amplitude and frequency response consistently converges to the desired filter response with a filter type offering operational stability.

Abstract: A method and apparatus are provided which detects distortion in a received FM signal caused by amplitude modulating and phase transition of two combined FM signals. A method corrects and modifies the distortion by detecting a distorted sample, replacing the distorted sample with an appropriate sample, and applying a smoothing process to the sample.

Abstract: A method for controlling audio gain balance in a multi-mode communications device (200) includes providing (201) microphone audio input to the multimode communications device. The audio is supplied to an amplifier gain stage while a dynamic instantaneous energy value of the audio input is computed (203) when in a first operational mode such as an analog mode. A predetermined gain algorithm is processed (207) representing an audio input when in a second mode such as a digital mode using the energy value. The audio gain stage in the multi-mode communications device is then adjusted (209) so that audio gain when in the first mode substantially approximates an audio gain when in an second mode. This provides a consistent audio amplitude output when receiving the first and second modes in a radio receiver.