CRT TV red / green vertical moving lines? (video link included)

[krs000a]

I just plugged in an old CRT TV manufactured by RCA in 1984 that supposedly has never been used before, but the first thing I'm presented with is not the typical static noise you would expect on such a TV, instead there is just a black screen with a red line moving from the left to the right, when it reaches the end of the screen it turns around and moves from the right to the left.
If I flick the RECALL switch from "2-13" to "14-83" the line turns green instead but does the same thing, just moving back and forth. If I push the CHANNEL UP / DOWN buttons I can make the line switch direction. Here is a video I made to demonstrate exactly what it looks like: https://www.youtube.com/watch?v=cz6zKsB4Hek
What does all this mean? Is the TV broke or is this normal behavior for an old CRT TV? I can not remember ever seeing this on any of the CRT TV's I had. I can't plug anything in and test the TV because it only uses indoor VHF/UHF antenna (no coax input) and the analog network doesn't exist anymore in my country.
Before I go thru the trouble and expense of obtaining a VHF/UHF-to-coax converter etc. I want to know if this TV is broke or not! Any suggestions?
PS: I am not a TV repairman or expert in any way as you probably can tell, so please don't get too technical, just explain so I can understand. Thank you so much for reading.