"Simple Simon"
** No such problem exists on any examples I have seen or heard about.Focus and linearity are both very good.
** ROTFL !!!I guess you are testing it with a fast rise and fall, lowish frequency square wave.
I guess you have never used an analogue CRO before either.
One of the nice things about them is the ability to visually judge rise and fall times from the brightness of the trace - where it is simply invisible, the times are *very* short.
Most digital CROs supply a false impression of slowness.
** Seems like you have one with a damaged / faulty CRT.** It is dead Simple - Simon.
....... Phil