How do I get rid of horizontal lines?

[Magnavox300]

Got it!!!!
Special thanks to mstaton, and Eric H.
I could never have done it without your expertise!!
I went back, and tried turning the Horiz.Freq alot further,
and slowly it started to get less and less lines, 5,4,3,2 then crystal clear!
I will plan on posting some photos of this great set within a couple days.
It's my first set, I could never have completed it without all the help from everyone here at VideoKarma!!

Magnavox300