Electronic system for the recording of periodically sampled variables

Claim 1

An electronic system for the analysis of television audience ratings by monitoring and processing into a recorder the code pulse signals received from the channel selector switch of a television set, said processing into the recorder being in the form of units of words of an even number of pulses each, said system comprising: a television receiver set having a channel selector switch, a generator of code pulses connected to the channel selector switch for supplying code pulses indicative of the station received, a receiver connected by transmission means to said generator of the code pulses from the station received, a memory for storing the code pulses of the station received, a comparator connected to said receiver for receiving the code pulses and for distinguishing them from the code pulses previously stored in the memory, a logic circuit connected to the memory and to the comparator, a selector switch connected to the logic circuitry, a recorder connected to the logic circuit and to the selector switch, a source of timing and control means providing timing and control pulses to the memory, comparator logic circuit, selector switch and recorder, a parity pulse generating circuit connected to the output of pulses from the selector switch and consisting of an inverter of said pulses and of a divider of the inverted pulses to provide an additional pulse which is added to output of the selector switch to insure that each word recorded always contains an even number of pulses, said recorder being activated by pulses from the comparator when the newly received code pulses at the comparator differ from the code pulses previously stored in the memory.