Motorola Corporation

Steven G Parmelee

Gary W Grube

Lawrence Marvin Ecklund

Gregory J Buchwald

Arthur J Edwards

Adelore F Petrie

Thomas F Karlmann

An adaptive graphic equalizer (200, 400) has various ordinarily fixed parameters (such as center frequencies, filter bandwidths, and step response sensitivity) that are automatically altered to suit a particular audio source. In one embodiment, a radio (100) includes the graphic equalizer, and such adjustments are automatically made depending upon whether the user has selected the AM or FM reception band.

Adaptive graphic equalizer and radio using same

A personal communications device (100) includes a wireless transceiver (206, 207, 208) to allow a two-way exchange of user information, and to allow down loading of remote control signalling information. The latter can be transmitted via an appropriate transmitter (210 or 211) to facilitate remote control of a remote controlled device.

Personal communications device having remote control capability

An improved dual limit solenoid driver control circuit is disclosed in which solenoid current is sensed and provided as an input to two separate comparators (24, 25). Each comparator receives, during a solenoid pull-in (initial) period (T.sub.1), fixed maximum and minimum reference threshold levels which determine the maximum and minimum current limits (I.sub.max, I.sub.min) for solenoid current during initial pull-in excitation. Subsequently during a hold period T.sub.2 following the pull-in period, each of the comparators receives different maximum and minimum thresholds so as to establish holding solenoid current limits (H.sub.max, H.sub.min). The outputs of the compartors are connected as inputs to a set/reset flip flop (32) whose output controls the operation of a solenoid driver circuit (15). A monostable multivibrator (33) reacts to an initial control pulse (41) to produce a predetermined pull-in time pulse (43) that results in the maximum and minimum pull-in solenoid current limits. The comparator thresholds are provided by a fixed resistor divider circuit (27, 29, 31) which receives a pull-in signal from the monostable multivibrator. The pull-in period (T.sub.1) is independent of the sensed solenoid current, and the switching thresholds are fixed and independent of the magnitude of the solenoid current during the pull-in and hold periods. The above configuration provides improved performance and stability, and is readily implemented with just a few components.

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Crystal Lake, IL, United States of America

Steven G Parmelee