05802167 is referenced by 107 patents and cites 13 patents.

A hands-free device is adapted for use with a cellular telephone in a car to permit hands-free operation of the cellular telephone, and includes a main terminal, a secondary terminal, and a microphone provided on one of the main and secondary terminals. The main terminal includes a first casing, a power supplying unit, a voltage regulating circuit, a first connector, an audio output amplifier circuit, and a sound output unit. The secondary terminal includes a second casing, a second connector connected removably to the first connector, a third connector connected removably to the cellular telephone, a hands-free control circuit, a voltage output control circuit, and a gain control circuit. The secondary terminal can be replaced so that the hands-free device can be used with any type of cellular telephone without changing the main terminal.

Title
Hands-free device for use with a cellular telephone in a car to permit hands-free operation of the cellular telephone
Application Number
8/745493
Publication Number
5802167
Application Date
November 12, 1996
Publication Date
September 1, 1998
Inventor
Chu Chai Hong
2F, No. 83, Min-Chuan Rd., Hsin-Tien City, Taipei Hsien
TW
Agent
Michael Best & Friedrich
IPC
H04M 9/00
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