My memory of the exacts here are fuzzy, but I think this depended on whether or not your TV picked up digital signal, analog, or both. I remember around that time we had a TV that would pick up static on some channels and have a blue input screen on others.
The way digital works you would either get a "No signal" indicator (because the circuitry detects the signal to noise ratio is too low) or squarish artifacts (because of the way the compression algorithms for digital video are designed).
I remember back in the Wii days when I was young we had a flat screen that would go to the digital pattern with no input. However sometimes once in a while it would get that static loud no signal so I think mine had both
I don’t really have a point here just wanted to share
Yeah, for instance the semi-ubiquitous "small TV with a vhs player built in" that was in a ton of mini-vans and kids' rooms well into the early 2000s only supported analog cable/antenna signals, so it would give the black and white static when there was no signal.