Took me 9 hours over 3 nights to get my NES working on a modern TV, and the fix was a $12 box
I decided to hook up my old NES to the flat screen in my Denver apartment and figured it would take 20 minutes. Wrong. The picture came in but every game looked like a fuzzy mess with a half second delay, so I went down a rabbit hole of RF switches, then composite cables, then reading forum posts from 2009 about upscalers and refresh rates at 2am on a Tuesday. I ordered the wrong converter twice, returned both, and finally grabbed a cheap composite to HDMI box from a game shop on Broadway for $12.99. The thing that killed me was the delay, not the picture. I tested Duck Hunt and it felt like the light gun was drunk, and that is how I figured out my TV's game mode was off the whole time. My wife thought I was losing it when I moved the console to a different outlet to check for interference. Turns out old hardware and new panels just do not get along unless you flip the right settings, and nobody selling those converters tells you that. How many of you have fought a modern TV to get an old console running, and did you ever get the light gun to feel right?