For example, during times when subscription television signals are not being transmitted, the subscriber demand switches 33 may be operated by the subscribers in a voting mode or shopping-at-home mode in response to program material provided via the non-subscription television channels.
In a subscription television system wherein subscription and non-subscription television signals are distributed from a central station via a cable distribution network to a plurality of subscribers, a switching station comprising: first coupling means for connection to said cable for receiving a composite signal including said television signals and interrogation signals from said cable and for providing return signals to said cable; signal splitting means connected to said first coupling means for separating the received signals; a plurality of switching means each connected to said signal splitting means for receiving said subscription television signals therefrom; a plurality of signal combining means each connected to said signal splitting means for receiving said non-subscription television signals and to respective ones of said switching means; a plurality of second coupling means connected to respective ones of said signal combining means for providing television signals to respective subscriber drops; a plurality of sensing means connected to respective ones of said second coupling means and to respective ones of said switching means each for providing a switching signal to the corresponding one of said switching means when the presence of a subscriber demand signal is detected thereby; and interrogating means connected to said signal splitting means for receiving said interrogation signals therefrom, to each of said sensing means, and to said first coupling means for providing a return signal indicative of the signals from said sensing means in response to said interrogation signals.
Such systems also involves physical collection of the tapes.
Those skilled in the art will realize that the pass bands of the various sections of signal splitter 23 will necessarily correspond to the frequency allocations of the various signals.
Parity checking can also be incorporated, if desired.
The junction between winding 45 and diode 47 is connected by a diode 55 in series with a resistor 56 to junction 54 which is further connected by a capacitor 57 to circuit ground.
The television signals from signal combiner 124 are coupled via the high pass section of diplex filter 124 and capacitor 26 to subscriber drop 27.
I switching station to generate a return signal indicative 3.