As tomlee59 writes. A CRT is very much a case of 'Have power. Will excite the phosphors.' Everything else depends upon inputs from elsewhere. Rotated or non-rectangular display? Talk sternly to the yoke or bias magnets. Squeezed, undulating or quivering display? Interrogate the deflection circuitry. And so on. If warm-up time is unduly extended you have to suspect heat-sensitive components, needing time to rediscover their original values. Take your pick where these are to be found. Gives one a new understanding of Apple's (and other companies') "pluck'n'chuck" style of Service Source directions for repair.

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