Looks like your vertical deflection circuits aren't working. Instead of a full raster from top to bottom, you have the classic horizontal stripe.
Don't run it for long periods with that bright horizontal line, or it may burn a dark strip across your CRT.
Have you replaced any parts on this TV? If not, caps in the vertical seem like a good starting place.
Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html