Apparatus for blocking voice band signals when receiving caller identification information for a waiting call

摘要

An improved caller identity on call waiting unit permits caller identification signals to be received without changing the direct current state of a customer telephone station. This is accomplished by using a capacitor/inductor circuit with appropriate bypass to accomplish the function of blocking voice band signals to and from the station. Advantageously, such an arrangement avoids the problem of falsely disconnecting calls on hold.