you can use a 12" monitor circuit with a 9"
tube. Did I made it easier for
you? :o)
I can understand how that can be so, but I didn't assume it was true.
I certainly have never tried it (though now I might).
Most of mono monitors are the same. Never had a different tube that I
couldn't exchange between boards (but you have to use the same yoke coil
from the board - you just swap the glass tube). I used
tubes from 5" to 12"
in the same board. All of then worked the same, with
retouches on the pots
(width, height, bright, so on)