I stumbled upon this today, and it’s something I’ve never heard of before. Most of you probably know about the Max Headroom broadcast 1987 Chicago. However, there was an earlier event like this in the UK:
The Southern Television broadcast interruption was a broadcast signal intrusion that occurred on November 26, 1977, in parts of southern England in the United Kingdom. The audio of a Southern Television broadcast was replaced by a voice claiming to represent the ‘Ashtar Galactic Command,’ delivering a message instructing humanity to abandon its weapons in order to participate in a ‘future awakening’ and ‘achieve a higher state of evolution.’ The broadcast resumed its regular programming after six minutes.
Subsequent investigations revealed that the Independent Broadcasting Authority’s Hannington transmitter had rebroadcast the signal from a small but nearby unauthorised transmitter, rather than the intended source at Rowridge transmitting station. The perpetrator of the hoax was never identified.
The incident prompted hundreds of phone calls from concerned members of the public and was widely covered in British and American newspapers. These are sometimes contradictory, such as differing accounts of the speaker’s name and the wording of their message.
There has been a quite a few tv broadcasting hacks, in February 2013, someone hacked KRTV, a tv station in Montana, during a broadcast of The Steve Wilkos Show. The person actually hacked into KRTV’s emergency alert system to warn viewers of an ongoing zombie invasion in Montana. The hacker claimed that zombies were leaving their graves and had already taken over parts of Montana. He advised the viewers against approaching the undead assailants.