Well, the broadcasted video mentioned the name of one of the news anchors on one of the affected channels, and the first broadcast attempt even interrupted that channel's news show. So I think the video was made specifically for this hack. It's not like there was a YouTube for them to go to and search for weird shit on.
Say some folks of mischievous "hacker" bent, having stumbled upon a forgotten "home video" grade tape containing moments of such transcendent perfection as these, decided they were obligated to share them with the world. (This theory shares the same "intoxicants may have been involved" bit as the previous one i posted)
The principle of "a clipboard and a confident manner will get you anywhere" might well have gotten someone into two different rooms on that evening where they might have had a moment to sit down with a VCR and some vulnerable interconnect cables, before packing their big duffel bag back up and leaving quietly.
"May have" seems weak. Nothing about the second intrusion screams sobriety.
I’m always afraid when I hear someone copypasting Apple memos. Obviously they must have watermark, if not text glyphs (rn = m, and further UTF-8 incantations), at least subtly different phrasing depending on which department, or person, views it.
However it's true that the top invisible scanlines normally used for Teletext could have been used for this. My VCR did record them, I was surprised to be able to view Teletext pages at the time of recording, though they were full of distortion.
It would have been possible to filter that out though.
I think at the time VHS recorders were still mostly analog and would have been recognisable from their artifacts the same way a typewriter can be identified once found.
The mechanics of how they worked are actually pretty interesting, I highly recommend Technology Connections' video on the subject [1], as well as the one on closed-captioning [2] (and his series on analogue TV in general [3])
[1] https://www.youtube.com/watch?v=KfuARMCyTvg
[2] https://www.youtube.com/watch?v=6SL6zs2bDks
[3] https://www.youtube.com/playlist?list=PLv0jwu7G_DFUGEfwEl0uW...
No schools in 1987 had color laser printers with this technology (and I doubt many businesses did either). Any students trying to do something fishy would have had to make do with, at best, 24-pin dot matrix printers with color ribbons.
A warehouse door THAT SPINS AROUND? Really?
With crack investigators like this on the case, is it any wonder it was never solved?
"You're posting too fast. Please slow down. Thanks."
TWO HOURS AFTER MY LAST POST? Up yours, assholes.
I think its also possible that the the technically equipped people who did this were perhaps not thinking as clearly as usual that evening. Intoxicants may have been involved. There were some gifted organic chemists working out in the suburbs then.