Originally Posted by Mister Laz
I read forward and backward through the service manual and it doesn't mention anything about a geometry correction screen, and Google was no help either. From what I can read and find on Google, the geometry is fixed via the convergence grid screen. It looks like I'm going to have to make my own grid overlay with tape and string and manually straighten every point out. A bit of a daunting task but I'm not sure of any other way unless someone more experienced is able to shine some light.
Yes, the service menu geometry screen should look like the convergence grid screen but it will allow you to adjust the lines on all three of the guns to remove the bends in the picture.
You might try a geometry test pattern if you can hook up a laptop or desktop computer in order to show the image. I think the Hitachis allow you to bypass the internal grid when doing the geometry adjustments allowing you to use whatever grid you want. The Toshibas might be different.
You might also find geometry test patterns on calibration dvd's like Avia and Dve, though I haven't used them so I don't know for sure what is included. That would also require the ability to bypass the internal grid.
I tried a thread grid once but it didn't work very well, a string grid might be better. And yes it is a lot of work
I eventually had a grid (a pdf image provided by a forum member) printed on a clear material of some sort but I never got around to using it.
Some one on here may have an image of the the grid for your toshiba that you could have printed onto a clear material of some sort.
The Don't dump your crt thread is indeed the best place to get help with these sets.