Success!

Replacing the Sony CXA1145P video encoder fixed the yellow and green flickering completely.

This was the Mega Drive that behaved badly from a cold start and then settled down after warming up. Sony designed the CXA1145P to convert analogue RGB into composite video, so replacing it was a reasonable test once the fault appeared to be colour and video related.

Since the flickering disappeared after the encoder was replaced, the original CXA1145P is now the strongest culprit. I still can’t say exactly what failed inside the old chip, only that replacing it solved the symptom.

I broke the repaired Mega Drive in with some Metallic Uniframe Super Hybrid Armor.

As you can see, complete success, even with the fairly limited tools I had on hand.

I could really have used my Hakko 808 vacuum desoldering tool for removing that 24-pin DIP cleanly. It would have made life considerably easier.

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