Yes, I remember when I was a child flipping through the UHF channels on my black and white tv, visible in the snow and static on one of the channels I could see the shapes in motion of my next door neighbour playing on his Atari 2600.
That most likely was caused by an overpowered "RF Modulator" transmitting a strong enough signal for you to pick up. One popular model used UHF Channel 33 https://en.wikipedia.org/wiki/Sup%27R%27Mod
