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RGB on the 2068 is probably one of the most gratifying additions you can get. The problem is that there is no simple way to do it and few companies (if any) have any to sell. E. Arthur Brown did have one they were selling for $19.95 which installed inside the machine, stripped the sync from the video, and provided for RGB connections. The Timex Technical Manual also shows a way to add RGB by building a three transistor circuit to strip sync from the video for RGB operation.