On Monday 28 April 2008 03:06, James Sweet wrote:

The Trinitron tube has a "unified" electron gun, it's more marketing than
anything else, but in a nutshell it uses the same focus and accelerating
electrodes for all three cathodes. There are still three separate guns in
effect, just bundled into one tidy assembly. Electrically it is no different
than the three separate gun assemblies used in other CRTs.

You will not damage anything by disconnecting a cathode, the accelerating
anodes, grids, focus, etc will still be active.

OK, thanks. I will have a look soon if I can desolder the blue gun and see if
the screen still flashes blue. But first, I will look up all the parts after
the (blue) cathode driver transistor and use a strong magnifier glass to look
for broken solder joins and such.