TV displays "no signal"?

I have a six year old CRT TV that’s hooked to cable for normal reception through a Comcast converter. For an unknown reason when I tried to turn in on yesterday, it showed a blank scene with a “no signal” message displayed. After making sure that all the cable wires etc. were correctly connected, and that the proper channel (in my case “3”) was set, I checked the cable connection using another TV. This TV worked which makes it appear that the problem is caused by the TV unit not the cable box or cable connection.

The TV is a 19” Apex. Is there a simple at home fix that I can do to correct this malfunction?