Each of the four connectors on the monitor is BNC type. A cable can be
made to direct-connect the Macintosh to the Electrohome, using RG59 75-ohm
cable. Because the Electrohome can use the composite sync signal available
on the green video pin of the Macintosh video card port, essentially only
three video cables are needed. Each cable carries each of the video
signals and its accompanying ground line.