We have a b/w camera which is on about 300' of cat5, both power and signal, and is hooked to an old Gyyr DVR. Two problems, one is the picture is wavy (somebody thought it was really a ghost image on top that was causing the distortion.) The other problem is that when I stick a monitor on it, I can read license plates, (in spite of the wavyness), but when
you play it back, you can't. It's in a remote location, so it doesn't get monitored, but wer need to be able to read license plates. Any suggestions on the wavyness (how to get rid of it), and is the lack of clarity on playback a function of the dvr quality?? Any help would be appreciated.

One thing to check would be the record resolution of the DVR and the Display resolution of the monitor.

Well it turned out to be the DVR itself (an old GYYR). Once we replaced it, everything looked sharp again.