mrkite

Cloak & Dagger (1984) the whole plot is about secret plans hidden in a fictional atari cartridge. (edit: actually, that's the 5200 box style, my memory is failing me)

An F-Type adapter might help since it will allow you to plug the atari directly into the antenna port on your TV, no switch box in the middle. https://www.amazon.com/RiteAV-Female-F-Type-Coax-Adapter/dp/B00SNSB1EA

Sorry for the necro, but I just wanted to highlight this for others. I used the 1 transistor/2 resistor composite mod (no motherboard changes except for clipping that one transistor) on my 4 switcher, and the video was far too dark. The signal was around 300mV peak to peak, color burst was around 140mV. Changing the resistors in the mod to 9.1k and 4.7k boosted the signal up to around 600-700 mV peak to peak (color burst now where it should be at ~300mV) and brightened the picture up considerably. It now looks amazing, even after being passed through an Extron switch.