Strange, colecovision only works on flatscreen

[eggmanfat120]

I got a colecovision recently, and only now just got around to trying it out. I thought something was wrong with it, as there was an unbearable amount of static when played on my crt. I couldn't hear any of the sound. I later went to try it on my flatscreen, and voilà, it worked perfectly; despite the resolution being less. Why did this happen, it is usually the other way around where it doesn't work on the flatscreen for these type of systems.

[nanochess]

I think the base frequency is deviated, you can clean the zone around the crystal with isopropilic alcohol, and also the channel switch.

 

Also I believe there is some fine adjust in the RF module (two pots, one for color and another for sync) but I've never attempted it.

[Greg2600]

Had this happen to me, replaced the CRT and it was fine again. Prior to that I was going through a VCR to get it to work.