1
Charles E Conklin, Duncan Bruce: Remote telephone line switching and testing. Conklin Instrument Corporation, Sughrue Rothwell Mion Zinn and Macpeak, March 24, 1981: US04258236 (17 worldwide citation)

Apparatus for remote switching and testing of a four-wire telephone line system is disclosed. The telephone line provides four-wire service between a first location and one or more second remote locations. The switching and testing apparatus provides the capability at the first location of controlli ...


2
Charles E Conklin, Duncan Bruce: DTMF Activated remote telephone line switching and testing. Conklin Instrument Corporation, Bernard Rothwell & Brown, September 6, 1983: US04403119 (5 worldwide citation)

DTMF (dual-tone multi-frequency) activated apparatus for remote switching and testing of a four-wire telephone line system is disclosed. The telephone line provides four-wire service between a first location and a plurality of second remote locations. By using a standard twelve button or expanded si ...


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Conklin Charles E, Bruce Duncan: Appareil de commutation et de verification a distance de lignes telephoniques actionne par signaux multrifrequence a double tonalite, Dtmf activated remote telephone line switching and testing. Conklin Instrument Corporation, RIDOUT & MAYBEE, CA1179043

TITLE : DTMF ACTIVATED REMOTE TELEPHONE LINE SWITCHING AND TESTING ABSTRACT OF THE DISCLOSURE DTMF (dual-tone multi-frequency) activated apparatus for remote switching and testing of a four-wire telephone line system is disclosed. The telephone line provides four-wire service between a first locatio ...