Motorola Corporation

William Arthur Burzynski

Charles W Bethards

Michael W Null

Robert Martin Beckmann

Dennis Eugene Tomlinson

Fred Alan Reimers

William Henry Schwartz

An electronic pushbutton tunable radio (10) having various audio controls is disclosed. A single pushbutton (22) is utilized to implement volume, fader and balance modes of operation during which up/down pushbuttons (20,21) control the overall and relative magnitude of audio signals produced by four speakers (24-27) while at the same time a single display (17) is utilized to display, respectively, either the channel to which the radio is tuned, the relative magnitude between right and left speaker audio signals, or the relative magnitude between front and back speaker audio signals. The radio has tuning pushbuttons (14) for direct recall of preset radio channels in a tuning mode operation. The radio includes an audio mode pushbutton (23) which terminates the tuning mode and implements an audio control mode wherein the recall tuning pushbuttons (14) now serve as on/off manual controls for audio control circuits, such as the radio local/distant (L/D) circuit, while at the same time utilizing the display (17) previously utilized to indicate channel frequency to now indicate the operative state of the audio circuits controlled by the recall pushbuttons in the audio mode.

Radio with audio controls and associated displays

The synthesizer uses phase lock loop techniques to generate either the carrier signal for an associated transmitter or the injection signal for an associated receiver. A programmable divider controls the specific channel to which the synthesizer tunes the transmitter or receiver whereas operation in the transmit or receive mode is dependent upon which of two oscillators is coupled in the synthesizer circuit. The oscillators are designed to run at two frequencies having a difference equal to the intermediate frequency of the receiver. This allows the one output from the synthesizer to be used in both the transmit and receive modes.

Synthesizer

Growing community of inventors

Des Plaines, IL, United States of America

William Arthur Burzynski