Circuit arrangement for monitoring one or more subscribers in the case of incoming domestic calls, and identification of the calling subscriber in telephone private branch exchanges

摘要

The invention relates to a circuit arrangement for monitoring one or more subscribers in the case of incoming domestic calls, and identification of the calling subscriber in telephone private branch exchanges which are connected to a test and alarm recording device. The object of the invention is to construct such a circuit arrangement such that monitoring and identification of a disturbing subscriber can be carried out without any major additional circuitry or equipment cost. This is achieved according to the invention in that the call number of the subscriber to be monitored is designated in a dialling evaluator and, if this subscriber number is dialled, the calling subscriber is identified, the call numbers of the called and calling subscribers being transferred at the same time into an information memory in the test and alarm recording device, which produces a print-out of the two call numbers. IMAGE