Zenith 25" Color TV - Model A25A23W
Your problem is a bad connection on the CRT socket on the CRT driver board, a bad connection in the RGB driver supply from the video jungle IC or maybe even an intermittant Picture tube. the only way to tell would be to tap on the crt board while the sets playing with a non conductive insterment, and see if it changes. Now there is alot of HIGH VOLTAGE at this spot, so if you have no TV repoair experience Please stay safe and call in a pro to assist you. Good Luck
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