PRODUCTION OF TELEVISION SIGNALS 



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Considering the limited number of picture elements, a surprising 

 amount of detail can be transmitted with this television system. A 

 distant person can be seen and easily recognized and his motions can 

 be plainly followed as he talks into a transmitter, turns the pages 

 of a magazine and goes through other similar motions. Large-sized 

 pictures in a magazine can be seen as the subject turns the pages and 

 looks at them himself. 



Fig. 8 — Disk receiving apparatus. The observer looks through the shielding window 

 at a picture on the 36-inch disk 



An auxiliary television receiving system also accompanies each 

 transmitting set and enables the operator to see that he is sending a 

 satisfactory picture current out over the channel of communication. 

 This auxiliary or pilot picture is formed on the scanning disk itself. 

 A small fraction of the outgoing picture current is tapped off and 

 amplified to operate a neon lamp, which is placed behind the disk 

 ninety degrees around from the scanning beam. An image of the 

 subject may thus be seen on the scanning disk just as at a receiving 



