Radio postal system acknowledgement apparatus

Claim 1

In conjunction with a radio postal system of the type including an orbiting satellite having a transmitter and antenna for relaying message communications in a video signal format from a first ground station to a second ground station where recording is desired and wherein each of said message communications includes an electrical coding signal identifying said second ground station to receive said communications and an electrical timing signal identifying the state of completion of said message communications, the combination comprising: means cooperating with said second ground station for receiving said video signal message communications and for providing video signals representative of the relayed message information as an output thereof for recording at said second station; means at said second ground station coupled to said cooperating means and coded to respond only to those video signal message communications including that particular identifying signal associated therewith, and further responsive to the presence of said relayed timing signal to provide a signal indication as to the extent of receipt of said message communications; and circuit means coupled to said last-mentioned means and including a code signal generator and second transmitter responsive to the provision of said extent of receipt signal for relaying a control signal indicative thereof and of the particular ground station receiving said communication to said first ground station via said orbiting satellite to control the message communications therefrom, said circuit means including said second transmitter being selected to radiate signals from said second ground station to said satellite transmitter within a bandwidth substantially less than the band width of signals radiated to said second ground station from said satellite transmitter.