What's a few degrees?

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"Adrian Smith" writes:

I have an Iiyama Visionmaster Pro 410 with a severely scratched CRT face
which would not polish out. I replaced the entire CRT assembly including
scan coils with one from a scrap Dell P791 which uses the same type of tube
(Mitsubishi Natural Flat 17") but different coils. A quick check on the coil
resistances proved them to be the same readings as the original but I cannot
check their inductance. I connected the rotation coil and the coils for
convergence and found the image when powered up is sound geometry wise
indicating the scan coils are probably compatible.

However, the line output transistor seems to be running a few degrees hotter
than normal, but the unit worked fine for two days. The greyscale needs
adjusting slightly but this is not possible as I don't have Iiyama's
software to set it up.

It is too much hassle to swap the scan coils over between the two tubes and
I can live with the greyscale problem but would the monitor be OK long term
with these substitute coils? It was suggested to uprate the line output
transistor to a 25A transistor instead of the fitted 20A but I don't think
it will make much difference.

Any suggestions before I bin the old CRT?
Also does anyone have the service software for this monitor?

Any help would be greatly appreciated.

Adrian