Patent ID: 8793755

Claim:
A network interface device operable to connect subscriber devices to a cable television (CATV) network over which (a) downstream signals are transmittable to the subscriber devices; and (b) upstream signals are transmittable from the subscriber devices, the subscriber devices including a passive subscriber device and an active subscriber device, the network interface device comprising: a first signal splitter configured to conduct CATV signals towards a passive branch circuit and an active branch circuit, the active branch circuit including an active signal conditioner configured to modify characteristics of active branch signals conducted through the active branch circuit; a sensor connected to the active branch circuit, the sensor configured to determine whether power consumption of the active branch circuit is indicative of one of: a normal condition, an inoperative condition and an abnormal condition of the network interface device, the sensor further configured to (a) supply a first control signal which is indicative of the normal condition in response to determining that the power consumption is indicative of the normal condition; and (b) remove the first control signal in response to determining that the power consumption is indicative of one of: the inoperative condition and the abnormal condition; a selectable switch connected to the active branch circuit, the selectable switch having an activated position and a deactivated position, the selectable switch configured to enable communication of the CATV signals between the CATV network and the active subscriber devices when in the activated position, and the selectable switch configured to enable communication of the CATV signals to a signal reduction path when in the deactivated position, the selectable switch configured to assume the activated position in response to the supplying of the first control signal and to assume the deactivated position in response to the removing of the first control signal; and a phase cancellation circuit connected to the signal reduction path, the phase cancellation circuit configured to split the CATV signals communicated to the signal reduction path into a first signal and a phase-delayed signal, the phase-delayed signal being substantially equal in magnitude and opposite in phase with respect to the first signal, the phase cancellation circuit further configured to recombine the first signal and the phase-delayed signal to a single, reduced CATV signal, where the reduced CATV signal cancels the first signal.