SL70/RD218 not showing targets

[DreamQuest]

Chuck,

Thank you. I really appreciate the quick response.

Just wondering if there is a document that describes the 4 signals in more detail; Azimuth, Trigger, Video and Data I/O? My display is not showing targets, so I would assume no video.
But I also don't see a circular sweep. Is that also in the video, or Data I/O, or does it have to do with the trigger. Or is the trigger just the signal used to turn transmit on and off. Just guessing.

Thanks,

Ken