05590414 is referenced by 20 patents and cites 32 patents.

An adapter unit for a portable radio telephone is disclosed. The adapter unit is selectively used for either one of the data transmission and the hand-free operation in response to a control signal from the portable radio telephone. The signal paths for the data transmission and the hand-free operation may be established in the adapter unit when the portable radio telephone is attached to the adapter unit. The adapter unit may be activated upon a connection of the portable radio telephone and the adapter unit.

Title
Adapter unit for a portable radio telephone enabling either one of data transmission and hand-free operation
Application Number
7/818567
Publication Number
5590414
Application Date
January 9, 1992
Publication Date
December 31, 1996
Inventor
Goichi Sato
Tokyo
JP
Kuniyoshi Marui
Saitama-ken
JP
Agent
Banner & Witcoff
Assignee
Kabushiki Kaisha Toshiba
JP
IPC
H04B 1/40
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