E-mac Monitor Blurriness

the artist

My monitor has been acting up for a couple of weeks now, by going from crystal clear to blurry to very blurry to clear again throughout the day. My co-worker has been troubleshooting macs for a long time and said it might be the picture tube. But i wanted your advice to see if he should try to fix it himself(to save $) or take it to a professional tech, please help!...
sounds like the CRT (the screen) is on the way out. it can't be that old though? i had an old CRT that started going blurry. it also went dark. they all do eventually.