Focus Issue Mag T940
 

Need a fresh set of eyes for a moment. Mag T940 chassis with a 25BP22 pix tube running at 24KV on the anode, good 2AV2 focus rectifier yet I can't get a uniform focus. Set the control for sharp focus in the middle and the edges gradually blur going outward, focus the edges and the center is blurred. Tube tests strong on a B&K 467 with even tracking and 90% life, focus voltage varies normally when I move the stick in & out, can't get a solid read on the voltage being too low for my probe but it's there and my high voltage regulation is about what it should be with a known good 6BK4. Horiz out and damper both check strong and the picture isn't bloating on extreme highlights so I'm at a loss here, am I missing something?

Historically the focus has never been "stellar" with this set so maybe it's a flaw but I've had much clearer 23" sets in the past with the same tube, could use some ideas here.

Thanks

If you have a HV scope probe rated for the focus voltage I'd try scoping the focus wire to the CRT and seeing if it's somehow being modulated by the sweep a similar amount to the DC difference between focused center and focused edges.