Circuit arrangement for detecting an incoming call in a telephone set

作者： Preikschat Gerd Dipl Ing

DOI:

关键词:

摘要: A conventional telephone set (FE) exhibits a cradle switch (GU) which connects subscriber line (AL) with ringing element (RO) or (after taking handset off hook) dialling and speaking (WSO) is controlled by control unit (SE). The problem that the (SE), after has been taken hook, only fed via can thus not distinguish whether this an incoming outgoing call, since there no connection between According to invention, connected storage (S) stores information item corresponding valid signal. This interrogated request (TRA) confirmation (TRQ), hook.

freepatentsonline.com 本地加速

freepatentsonline.com UNKNOWN 下载加速

lens.org UNKNOWN 下载加速

参考文章(7)

Günther Weisigk, Arrangement for a telephone apparatus ,(1984)

Willhaus Werner Dipl Ing, Preikschat Gerd Dipl Ing, Device for reading status messages of a payphone ,(1987)

Rueff Joseph, SYSTEM FUER DIE DATENUEBERTRAGUNG UEBER DAS OEFFENTLICHE TELEFONNETZ ,(1984)

Erne Hansjoerg, GERAET ZUR UEBERWACHUNG DES LINIENSTROMES IN EINER TELEFONLEITUNG. ,(1980)

Luehmann Hans-Guenther Dipl In, Weise Guenter, Optical telephone call indicator - has power supply derived from calling signal using high impedance rectifier and capacitor ,(1980)

Wilhelmy Lothar Dr Ing, Dialling pulse signal generation in telephone systems - uses integrated circuit to provide pulse series from push button operated selectors ,(1978)

Strehl Herbert Dipl Ing, Visual identification of called and calling numbers - is initiated by subscriber equipment and transmitted directly over connecting telephone line ,(1982)