78 traverse amplifiers 74 and 76 can be disabled by an on off signal applied to their inputs the inputs applied to amplifiers 74 and 76 and rate line 78 are transmitted from microcomputer 50 of fig2 multiplexer 66 selects according to the selection signal on line 86 from microcomputer 50 one of the signals provided by module 64 or 68 and transmits it on time shared line 84 multiplexer 66 similarly transmits on line 84 a digital signal from pixel locator 88 which signifies the location of the picture element being transmitted by camera 16 clock 70 has two separate pairs of lines connected to locator 88 and camera 16 to synchronize them clock 70 has another output commonly connected to modules 64 and 68 to synchronize them the video output of camera 16 is coupled to video buffer 90 which provides a video output on line 92 the following group of lines identified as group 94 is coupled to microcomputer 50 lines 78 84 86 92 and the input lines to amplifiers 74 and 76 in this manner the microcomputer can monitor and control the operation of the equipment of fig3 to facilitate an understanding of the principles associated with the foregoing apparatus its operation will be briefly.