The screen lines are a thin light line that moves upwards (somewhat like old tv screens used to do when their vertical setting was off) followed by a dark section then another light line, over and over so there's always two light "line" areas on the screen at a time, both moving upwards. I used an RF switch back in the 90s without screen problems, and my NES toploader has screen lines using an RF switch but they're uniform and stationary. A couple games seem to save okay, but the Landstalker saved game was wiped out of memory when I tried loading it.