[robryk]

Similar incident: in 1985, political opposition in People's Republic of Poland "hijacked" TV by broadcasting in sync with the actual TV signal. This allowed them to superimpose things on top of the image (within some range around their transmitter), which they used to broadcast political messages.

Differences: not complete replacement, but superposition; "attacked" signal was the final signal to consumers; the hackers were caught (by standard police methods).

Some details: https://hackaday.com/2016/07/05/retrotechtacular-how-solidar...

[pomian]

That was brilliant! Great that they made the write up on hackaday, for posterity.