Max Headroom newscast hack
One of the most notorious pirate broadcasts of all time, preserved well beyond its intended lifespan, occurred on November 22, 1987, during a Chicago station's nightly local news broadcast. After turning black for 15 seconds, the picture reappeared but now showed a person wearing a Max Headroom mask, situated in front of a rotating piece of corrugated metal and accompanied by a humming noise. Technicians at the station managed to halt the pirated broadcast by switching the microwave transmitter they were using to broadcast, suggesting a hack by a strong pirate microwave signal nearby.
That same night, PBS member station WTTW fell victim to the same hackers during a broadcast of the Doctor Who episode "Horror of Fang Rock." This time, the pirates were able to cut in for a full 90 seconds, and used the time to spout advertising slogans and seeming nonsense. The clip ended with the Max Headroom mask-wearer pulling down his pants, receiving a spanking from an unidentified person in a French maid outfit, and yelling "They're coming to get me!" The WTTW broadcast was being sent from the Sears Tower microwave dish and because there were no technicians on duty at the time, they were unable to trace the signal.
The identity of the hackers and what the videos mean beyond a simple joke remain a mystery to this day. Occasionally, the wide world of the internet will stumble across a character that seems like they could have pulled off the Max Headroom hack, only to dismiss the theory later. The most current thinking on the subject suggests it was someone within the Chicago Broadcasting Community because the technology required to pull off a huge microwave hack wasn't available to the average consumer in the late 1980s.