04644347 is referenced by 137 patents and cites 4 patents.

In the preferred embodiment the multiple frequency receiver comprises a decoder responsive to a transmitted coded message signal having a special code for designating that the message is being sent on the local frequency and which is also responsive to the absence of the special code which indicates that the signals are being transmitted on a designated nationwide frequency. The decoder includes a microprocessor which generates an output to turn on the local frequency channel element so that the pager may receive the local frequency when the special code is detected and generates a second output to turn-on a nationwide frequency channel element so that the receiver can receive a nationwide frequency when the special code is absent. This enables the pager user to transfer from his local city to another city without having to manually adjust the pager.

Title
Multiple frequency message system
Application Number
6/522066
Publication Number
4644347
Application Date
August 10, 1983
Publication Date
February 17, 1987
Inventor
Jerome C Leonard
Plantation
FL, US
Alfred R Lucas
Coral Springs
FL, US
Agent
Donald B Southard
Anthony B Sarli
Joseph T Downey
Assignee
Motorola
IL, US
IPC
H04B 7/00
H04Q 7/00
G08B 5/22
H01H 67/00
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