schaltungsanordnung to a central review of the state changes of a connector arranged at the exit schaltmittels in telecommunications, in particular telephone

摘要

Pulsing contacts are in a station supplied through a line affected with capacitance, and are tested by an indicating switch at the beginning of the line in the exchange. It evaluates the current in the subscriber line, changing when the contacts are operated. A constant current source is connected in the exchange to the subscriber line at least during the testing period. A capacitor is connected across the line, so that when the tested contact is operated, the capacitor charging current abruptly reduces the voltage apllied to the indicating switch below its specified response level.