Retrotechtacular: Max Headroom Takes Chicago In Audacious TV Hack

Those of you with long memories and a compulsive TV viewing habit might remember [Max Headroom], a quirky piece of TV ephemera from the late 1980s and early 1990s. [Max] was a supposedly computer generated TV show host and VJ with a pseudomechanical stutter, a slightly blocky rendered head, and a moving background of rendered lines. He looks a little quaint for viewers with a few decades viewing experience of CGI, but in his day he was cutting-edge cypberpunk TV.

He also made unscheduled showings on two Chicago TV stations in an audacious hack that has never been explained and whose culprit has never been found.

The real [Max Headroom] (Fair use) Via Wikimedia commons.
The real [Max Headroom] (Fair use) Via Wikimedia Commons.
If you were a bored British teenager and future Hackaday writer vegging out in front of your parents’ TV on an April night in 1985, you’d have caught [Max]’s genesis. He strung upon us by rising out of a title screen full of static in the Channel 4 TV movie [Max Headroom]: 20 Minutes into the Future.

The plot is a trip in itself. An investigative journalist seeking to uncover the sinister owners of his network (they run speeded-up adverts with the unfortunate side-effect of causing overweight viewers to explode) is pursued, causing a road accident in which he is injured by a collision with a safety barrier. Hence the name: [Max Headroom]. The network try to cover it up by producing a computerized facsimilie of the reporter which turns out to be an embarassing failure. They scrap the computer and it falls into the hands of a pirate TV station operating from a decrepit campervan, the Alphabetti-eating proprietor of which turns the character it contains into a TV sensation. Meanwhile the reporter escapes, recovers, and prevails over the villains.

The [Max] character proved to be something of a hit, with a TV spin-off series, VJing, adverts, and more. But that wasn’t the whole story of his appearances, back to that unexplained hack of Chicagoland TV.

The Chicago fake [Max Headroom].
The Chicago fake [Max Headroom].
On the night of the 22nd of November 1987, viewers of WGN were watching a sports program when the screen went blank and they were treated to a few seconds of a slightly home-made [Max Headroom] dancing in front of  those trademark moving lines. A couple of hours later on WTTW a rerun of a [Doctor Who] episode was again interrupted with the same fake [Max], this time speaking for a while before, if his performance wasn’t already bizarre enough, being spanked by a woman whose face is off camera.

As a piece of television history it’s an intriguing mystery, though since so little is known about the mechanism through which it was achieved it hasn’t achieved the notoriety in the technical world that you might expect. The stations involved conducted full investigations at the time and failed to locate a culprit, perhaps they should have been looking for that old campervan with the antennae on its roof.

It is very unlikely that a similar stunt could be performed today, with entirely digital TV studios and easy access to encryption technologies for external links to transmitter sites. But in the 1980s a studio would still have been an analogue affair so there would have been more opportunities to insert an unauthorized feed. Next year sees the 30th anniversary of the event, it would be fascinating if the perpetrator would mark it by anonymously revealing how it was achieved. Of course, we’d love to hear how you would have done it in the comments below. Surely we have readers who are intimately familiar with the television broadcasting equipment of the time.

Below the break we’re showing you both fake [Max] intrusions into the Chicago airwaves. First is the short outing on EGN, below that the longer one on WTTV.

This isn’t the first time we’ve brought you a TV hack from the 1980s, earlier this year we brought you the tale of some very clever overlaying of messages from the independent Solidarity trade union on the TV transmissions of the Communist Polish state.

[via Hacker News]

47 thoughts on “Retrotechtacular: Max Headroom Takes Chicago In Audacious TV Hack

        1. microwave injection is most likely, ive done it in CT. all the stations had an agreement on who uses which channels on the 2 ghz microwave that we all used to send news feeds from the field. a station that was supposed to be on 2 ghz ch7 was on ch 2 that night. ch 2 was agreed to be used by my station. they were feeding tape for an hour at least and i couldnt check in my signal to my transmitter site. we needed to feed tape at 10pm while the other station was live on the news, no one answered the phone at the other station, so i decided i needed to swamp their signal to get them to move to their channel. i pointed roughly at their antenna and powered up. i knew they had a 10 watt microwave and my new truck had 13 watts. i ended up taking out their live report with my stations color bars and tone.

        2. I think that’s what they thought at the time. I remember hearing about it on the news. Then, later, I went to watch a recent Dr Who, and discovered I had it on tape. Might still have it stashed away, somewhere. It was such an oddity, that I think I kept it.

  1. Oh god now this crap has spread to Hackaday too? It’s bad enough that it’s already some kind of meme on reddit, but I figured this is the last place I’d see the meme spread to.

    Every few weeks someone posts about this on reddit, and every time there a bunch of people making out like it’s just the craziest thing to have happen since sliced bread. I don’t get it. There’s even a group of reddit users that seem to team up and downvote anyone who says that this “incident” really isn’t that interesting. It’s damn weird!

    Some guys wore a mask and transmitted a signal, a lot weirder and more interesting shit has happened in the DECADES since this happened.

    1. I agree, and I felt that way at the time. There seems to be no point to it. I suspect, as others have said here, that it was inserted into a microwave link at some point. An antenna and a transmitter, it doesn’t have to be more powerful than the station’s transmitter. Just closer to the receiver and close to the signal path.

      I think I’d have looked along the paths of the links for a mountain, hill, or building that was close to the signal path.

      The pointlessness of this makes me think it was teens who did this, and that someone’s parents figured out it was their kids and clamped down on this so as not to get caught.

  2. I was around at the time – watching late night Doctor Who in fact – and the answer was supposedly a van witha satellite dish aimed at the main transmitter. But that didn’t really make sense to a lot of people who had any technical background. Be nice to know how it was done.

    1. I don’t see why it would be so hard to understand… You don’t attack the main transmitter – that’s hopeless. Instead, attack what feeds the transmitter.

      Many broadcast transmitters on top of mountains were simply relay transmitters. The studio (in the city at the base of the mountain) would transmit the signal to be broadcast to the mountaintop transmitter using a private microwave radio link. If you knew enough about how the link worked, and could replicate it well enough, it simply becomes a matter of overpowering the link with your own signal.

      The Max Headroom intrusion appears to be exactly this kind of attack. It might be tricky to get all the details exactly right (like missing or badly distorted audio), but they appear to have had a good grasp of the video details. They got close enough.

  3. ”[Max] was a supposedly computer generated TV show host and VJ with a pseudomechanical stutter, a slightly blocky rendered head, and a moving background of rendered lines. He looks a little quaint for viewers with a few decades viewing experience of CGI, but in his day he was cutting-edge cypberpunk TV.”

    That is not factual, Max Headroom was only made to look like it was CGI but he was actually played by an actor with some kind of latex mask. The only element that was computer generated was the background as far as I know. Also, I am not sure why this is a front page hack-a-day story…

    1. “That is not factual, Max Headroom was only made to look like it was CGI but he was actually played by an actor with some kind of latex mask.”

      That is what “supposedly” means.

      ”[Max] was a supposedly computer generated TV show host…”

        1. Is English your first language? That’s exactly what “supposedly” means in that context. Everyone knows it was Matt Frewer with a mask.

          What’s interesting about the pirate-TV version, is that even the background wasn’t computer generated, it was the guy’s mate waving around something like a garage door.

  4. I was watching Dr Who at the time, and freaked out. Our cable company carried 11 and Who was on late and then they signed off afterward. The microwave service that carried it to Lafayette put another commerical Chicago station on after 11’s sign off. Since there are aditional fees to be had for the other channel Lafayette had to squelch it. Every time change (Indiana didn’t) Dr Who would get clipped off mid show, argh! When the Pepsi advert with the spanking started I thought our cable outfit was responsible till it was allmost over, then back to the Tardis. That microwave link would have been a hackable entry point, but only to bother people in the distant city not Chicago.

      1. I’d use a different word, even if I’m not sure what. There’s no doubt, the character is computer generated. Just like Spock is a Vulcan. But to make tv shows, rubber pointed ears are put on a human actor to make Spock, and a human actor pretends to be a computer generated character on “Max Headroom”. There’s no uncertainty, about the character on the show, or how it was “generated”.

        Michael

        1. It was “supposed” to be computer-generated, in the context of the show itself. In reality it wasn’t. Yes, everyone knows that, “supposedly” doesn’t necessarily imply uncertainty. That would be “apparently” or “possibly”.

  5. I am fortunate to have seen it live that night on WTTW during Dr. Who. Being the stereotype of one who watched that kind of program at that time, the Max Headroom Incident was very cool indeed. Anyway, I always believed it was done by hijacking or overpowering the microwave link between the WTTW broadcast studios and it’s transmission antenna located on the Sears Tower.

  6. Back in the early 1980’s most Dutch households were hooked up to a central antenna system which picked up broadcast channels and redistributed them in the city or town. In Amsterdam some clever cookies figured out that you could easily take over a channel by just beaming a signal to the antenna tower from a nearby rooftop or window. Thus the TV pirates stations were born and every evening, after the regular transmissions had ended, they would keep the city awake with hard-core porn and Thunderbird reruns. Good times!

    1. Not tv, but in 2007 the famous Copenhagen squatters house “Ungdomshuset” had a pirate FM transmitter and pretty powerful. On my car stereo I could pick it up 10-15 miles away. They were transmitting death metal, extreme left manifestos and kid shows where the police always were the bad guys. It was quite hilarious and kind of sad when they eventually went silent. They were on top of a popular POP channel and blocked it completely. Googling around there was, and possible still is, an Anarchist web site in multiple languages on how to modify an ordinary radio as a local oscillator, how to modulate it with audio and how to build the PA and with components you might have at hand.

    2. VHS tape players usually had an RF modulator for television sets without proper inputs, and if you connected that to the antenna socket instead of the television, you could watch the videos in every room of the house, or even in your neighbor’s house, assuming they were on the same stretch of cable.

      Lots of small pirate channels were made that way, covering a single building or a row of houses. Never really tried if it would broadcast any distance through an antenna, but that would have been a possibility as well.

  7. The last word before the two videoes is “WTTV”. WTTV is channel 4 out of Indianapolis, which at the time of these intrusions was an independent station. It’s now Indy’s CBS affiliate. Regardless, it had nothing to do with the hacks. You meant “WTTW” there.

  8. Let’s see.. There was basically no security, remote access over FOSSIL.. PPP.. AT-modem etc, and digitized queued playback.. Inside job or someone who worked at McDonalds during the day spent two-hours reading about computer security in it’s entirety for that time.. War-dial an area code and enter a password and reverse the light-weight protocol through black-box logging..

    I’d bet my life it wasn’t RF piracy the guy in the video looks like most average joes do when they do something technical and it works..

  9. I’m not that sure if it would be that difficult to do now. Generating digital TV signals is not so hard with SDR. They are commonly encrypted, but the receiver will usually accept clear video as well in the same configuration. Most homes are using cable (at least here), so attacking the network to cable head-end link is probably what you want. I have seen two dominant technologies: a wired fibre link to the station, and getting the signal off a satellite feed. If you are close, it should be possible to overpower the satellite signal without too much difficulty, even if the antenna is not aimed towards you.

    You could also try to inject the signal directly into your cable outlet. Very few cable companies use distribution boxes with isolators on every tap. Usually there is an amplifier every n taps, and then boxes that have a simple inductive splitter. The signal should travel downstream fine.

  10. The old 80’s/90’s studio links were pretty easy to take over.

    First you would have to scout out where the studio link transmitter was in the 2ghz band at the office for the tv station the feed comes from. (Calling the FCC/IC and asking would have been suspicious)

    You would have to pre-record what you wanted on a VHS or betamax then park a van or RV near the tower.

    For the transmitter you would have to figure out channel had harmonic that you could add another signal too in a mixer (And build the appropriate filter to only let the harmonic through) with whats crystals you could add to that harmonic to match up your NTSC carrier in the center of where the studio link carrier was.

    Amplification can be done with an NPN transistor, You could get a watt pretty easily and if you got close enough you could take it over.

    Back in the 80’s it probably would have required some experimentation to find one at radio shack that would have worked at 2ghz.

    If you had test equipment or bought new parts for the project you could work with the fundamental off the VCR on channel 3.

    Funtip, Most smaller radio stations still use UHF studio links with two wide band FM carriers to feed their towers.

    You can take over one channel of audio with a $50 Chinese ebay radio.

    But doing any of these things would be in violation of the radio communications act.

  11. The basic idea is to overpower the STL, Studio Transmitter Link. This is the link that moves studio programming to the main transmitter site, I believe WGN was/is in a chicago high rise.The STL specifics are FCC public record, the frequency, power output, and lat/longs of both ends of the link. Overpower could be accomplished multiple ways, massive amplification of the pirate signal, either electrically (difficult/expensive), larger dish (cheaper, but not portable), or move your whole rig as close as possible to the receive antenna. If he could get close enough to the RX side he could probably do it with a 2′ parab and some reasonably portable equipment. Perhaps this guy had roof top access nearby along the STL path.

    Some interesting issues. The STL link would be FM modulated analog video, occupying 30+ mhz of spectrum, audio is created using subcarriers, back then I suspect one or more including 5.8mhz, 6.2 mhz, 6.8 mhz, and 7.5mhz. In other words, a video signal that did not exist on the back of any retail consumer equipment. The fact that his video includes audio is interesting. I believe the FCC license would list the subcarriers, but just because the station applied for them didn’t mean they would be used, or they could be used to carry non-audio traffic like control data. It looks like he guessed wrong on the WGN subcarrier but was closer on the WTTW, or his video was poorly filtered and hammering his subcarrier.

    Whoever this guy was he was pretty competent. He would have to find the following. RF parameters; path frequency and subcarriers would have to be found through paper FCC records research. Path TX and RX; he would have to figure out exactly which dish on the high rise, and if not on the roof, which floor and window. He would have to find a place to intercept this LOS (line of sight) path between the high rise and the studio. With that knowledge he had to procure this equipment, buy it or build it. Buy new, I am going to guess $20K of 1987 money of broadcast quality gear that *only* TV stations would be interested in. Buy used, extremely doubtful because it usually heads to TV stations in smaller markets or sits on the shelf as an emergency spare. That leaves build it, a frequency agile transmitter with audio subcarrier(s) capable of passing FM modulated video, and the equipment to modulate said video, and make it all portable. Add to that the expense of the video recording equipment and quality playback gear that held sync. Finally add at least one accomplice who has kept her mouth shut for 30 years. Pretty friggin’ legit.

    My guesses. Pissed off broadcast engineer who probably built this stuff from spare parts and other items borrowed or stolen from his employer. I am going to ask some of the old hands at work what they think next week.

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