Been down this rabbit hole a few times over the years. The official explanation was always "pirate broadcast" but nobody was ever actually charged or identified, which is the part that always bugged me. For something that was supposedly just some pranksters with a signal hijacker, the authorities seemed very keen to drop it quickly and move on.
The voice itself is odd too, very calm and measured, not what you'd expect from someone pulling a stunt for laughs. And the timing - interrupting the news of all things.
I know some people reckon it was an inside job at Southern TV itself, like a disgruntled employee or something. That honestly feels more plausible to me than a random external hijack of that quality.
Anyone here looked into it properly? I'd be curious if anyone's found anything beyond the standard Wikipedia summary because I feel like theres more buried in old newspaper archives that never made it online.