I've got a rare old vector arcade monitor from a "Warrior" arcade game
that came out in 1979. Everything works except that the picture is way
off center. To the point that about half of it is off-screen. I've
adjusted the horizontal and vertical controls as far as they go. So
I'm thinking I need to adjust the yoke. But I've never done that
before. I tried loosening the screw and I can rotate it which rotates
the picture. But I don't know how to move it to a different angle to
get the picture back in the middle. It's an old b&w monitor so I don't
have to worry about color convergience or anything like that. Can
someone give a novice a clue on how to go about this? Thanks!

John