Common enough with older Toshiba models. What you are seeing is poor field linearity. The cure is to replace two capacitors, both are 2.2uF. One of them is near the i.f amplifier and the other is close to the field timebase output. Sorry, I don't recall the designations, but C317 seems to ring bells.
If you have no idea what I am talking about then you need to have it repaired by an expert. It is a simple enough remedy and should not cost too much.
Colin, November 2007
