monitor with screwed colour in bottom-right of screen

This is called a purity problem. There are basically 3 sets of adjustments to a colour CRT/monitor over and above the ones for a monochrome CRT : Purity : Getting the red beam to only hit red phosphor, etc Convergence : Getting the beams to hit dots next to each other Grey Scale Tracking : Getting the relative intensities of the colours correct (so that grey/white are neutral colours) Gettign the purity correct depends on having a good shadowmask (or equivalent in Trinitron, etc CRTs -- all these tubes work on essentially the smae principles!). You then use magnets on the CRT neck to deflect the beams slightly. Normally you set the thing up displaying a pure red raster, at which point you hope the other colours are right too! After setting the purity, you then have to do the convergence. This is set (on modern CRTs) with more magnetic rings on the CRT neck, and also by tilting the yoke slightly. I can remember, though, when there were a dozen or more electrical convergence controls, and when you had to set up the monitor in the position it was going to be used. Mind you, the results were worth it (I've nver seen a modern TV that has as good a convergence as my old Delta-gun Barco!). You mentioned in another message that this monitor has suffered physcial damage. And I may therefore have some bad news for you. Try hitting (carefully!) that corner of the CRT with the palm of your hand when the monitor is on. Do the colours change, and end up different? If so, then I suspect damage to the shaddowmask or its fixing (I seem to rememebr this is a Trinitron tube, the mask in those is a whole lot of thin 'wires' running veritcally down the CRT). Nothing much can be done about this short of a new CRT (even rugunning places can't normally fix this). -tony