Faking TV Remote Control with Paper and a Lighter

Cut slots into a piece of paper to represent the IR remote control bitstream for putting your TV into standby. Insert it between your TV’s IR receiver and the flame from a lighter, and pull the slots along to generate the coded pattern. Get it just right and you have a paper and lighter remote control. That’s just what [ViralVideoLab] did and you can see it in action in the video below.

Think of this as just the germ of an idea. Imagine how you’d automate this and extend it to include more commands. A wheel with the various bitstreams cut into the circumference comes to mind. A servo would turn the wheel to the desired command and something else would fire up the lighter just as the slots pass by. Now take it a little further. You already have a remote control with keypad and IR light. Hack that to talk to a microcontroller which would control the servo and the IR light. And there you go. A useless but fun hack (hint hint).

And before you do cry useless. Hackers are no stranger to making useless machines as long as it’s a fun hack. Take this world’s biggest useless AI machine for example. Or what about this book scanner with unseeing eyes. Or there’s this endlessly fun to watch classic useless machine that turns itself off, but with eight switches.

Thanks to [ttl] for sending us the tip about this.

114 thoughts on “Faking TV Remote Control with Paper and a Lighter

    1. Maybe paperboard. Could also laser cut something out of acrylic if you put an opaque barrier up.

      I wonder if barcode software could work to produce these? Might be a bit too close together but might be a starting point.

      Obviously easier to just send the correct IR signal but you could also make a version with movable gaps that would allow you to not have to make several fixed ones.

      1. Yes, exactly. It’s looking for a differential and time between edges. No carrier needed – cheap & easy.

        When I’m welding with my auto-darkening welding mask, I test it by fanning out my fingers and waving them quickly in front of the light sensor. This sudden change from bright/shadow is enough to trigger the LCD shutter, and give me the reassurance I need to look directly at (what is about to be) an arc of electricity.

    1. Not all. I had a TV which remote just made a train of short pulses the information coded in the spacing. The absence of a carrier was probably the reason it was easily jammed by a CFL with electronic (high frequency) ballast in the warm up phase. They emit more IR during warm up. The good thing: it still worked with it’s original two AAA batteries 15 years later. It consumed nearly no power.

      1. The cheapest way to get IR is to put in a standard IR module, which is a simple circuit integrated into a IR receiver and can be had for 5 or so different frequencies in the 30+KHz range.
        Even $6 TV dongles have one on them.
        So no saving money won’t cause it.

        So this is likely fake I would think. Or it only works on a single make of TV from some odd place like north korea?

      1. The TV doesn’t really have the choice. The carrier frequency is hard-wired into the IR module inside the TV, I seriously doubt there is any mass produce IR receiver that wouldn’t have a hard-wired frequency filter.

        1. This made me wonder about how the IR receiver modules actually work.

          To filter you need phase shift and the biggest capacitor you could fit on the IR decoder chip would be micro small so you would need a huge resistor to get the such a low filter frequency. Resistors aren’t easy to make on a die either so I wonder how the filter is constructed.

      1. That seems like an incredible explanation, the guy just happens to try this out of the blue and it works because incredibly his lights flicker at the carrier frequency.

        As opposed this is your standard youtube prank.

        Oh well, anything is possible I suppose.

  1. If someone could please make a ‘TV-B-Gone’ on a Möbius strip of paper… :D

    Now, it should be possible to send codes to a device with only the lighter… arc lighter maybe?…

    1. See, moving from a sheet of paper to a tape is an interesting proposition.

      If it works with infrared generated by flames and the like, you might be able to create a neat steampunk TV remote. Simply create a half-centimeter tall tape with various patterns in it, and run that past a small lighter-based burner, with a shutter to select particular codes. The whole think could probably fit in an unusually thick TV remote, and in theory could be entirely clockwork.

      1. My mind runs amok on this: Why didn’t McGyver do this in an episode? What about a fireworks fountain (some of them flashes rapidly) carefully layered with varied thicknesses of clay and flash powder, or a carefully layered chrysanthemum bomb that could a TV-be-gone of mass destruction, the equivalent to a neutron bomb over a city but only affecting tvs?

  2. Could the lighter possibly flicker at the required frequency? Haha, or maybe the LED lights. What about the tape that was placed over the cuts? I need to know this wasn’t a fake vid…
    .
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    It is.

    1. Dammit! Nice article, HAD.

      Still, it’s a nice idea… Maybe a second disc to create the 38KHz? A spinning disc with the appropriate notches, then drag your strip past that. I’ve a feeling it’d need to be quite large. Or perhaps some lenses and some very tiny notches, maybe laser printed on acetate or something.

      One giveaway on this video is that there is no “universal standby signal”. Anyone who’s tried to get a cheap universal remote working knows that. That, and the putative signal is too short for IR TV remotes. Not enough bits.

      Still if it weren’t bullshit it’d be a nice example of electro-mechanics, the same way Baird’s first TV worked. Or early IBM accounting machines, or early teletypes / TELEX. Lots of early machines used mechanisms for digital processing.

      1. > Maybe a second disc to create the 38KHz?

        Pretty fast, I’d say. OTOH… a piezo transponder tightly attached to the lighter… or no, scratch that: let the flame live in a transparent tube n*(lambda/2) (I’m assuming both ends open, the air has to come in from somewhere), excited by a piezo. At 38kHz lambda is about 8.95mm. Some tuning might be necessary ;-)

        Flame in a quartz tube… might pass the steampunk test.

        1. Pretty fast, but that depends on the size of the disk! Then again don’t some RC model motors spin at ludicrous speed? But given a big enough disk, or small enough notches, it could be done.

  3. I just felt like coming along and adding “…BUT TEH 38KHZ!?!” to the chorus. I have a bunch of IR modules and have done IR TX/RX with TV remote control parts and like many people I find it hard to believe this works.

  4. I’m just wondering if you could do that with only black ink/toner without cutting any slots in the paper. It will probably need some more input power (maybe a bright flashlight or so).

      1. Any old fashioned tungsten light bulb will do. Glass is transparent below around 3-4µm of wavelength. Of course you could just use a suitable LED. Even my phone has an included IR LED, but luckily I don’t need a paper strip to operate it with the right patterns. :-)

      1. Yeah, but ancient aliens were around. The facts are on the history channel on TV so it must be true!!!!!!!!

        (stands back and watches a load of fools become alien-theory-hipsters over that blatant misinformation)

  5. It works perfectly well when you replace the remote control’s LED with a mic’s connection and record the signal as a sound, then play it back while attaching an LED to the speaker’s connection. So, it certainly isn’t about the 38kHz clock on the remote control.

      1. Bandpass, Use a peasant grade “HD audio” at low bit rate and force 8bit if available (without dithering) and possibly add a low pass, generate an opposite of the highpass filtered carrier to counteract and (hopefully) eliminate the carrier altogether.

        And then there are some many more ways……..

        1. Okay, it’s obviously possible. My (admittedly not very well made) point was that being able to record and replay the signal does not mean the 38kHz carrier is irrelevant, espacially since Rohitasch did not mention any filtering.

    1. I had a program which turned a HP48 calculator into a learning remote.
      But in the description it said, that the CPU is to slow to do more than 32kHz of sampling frequency. It still worked with Sony remotes, which used a carrier, but the range was lower than with the original.

      1. The carrier filtering in a 3-pin IR receiver is analog. Meaning that signals that aren’t exactly 38kHz aren’t outright rejected, just attenuated down the further away from 38kHz they are. Hence the reduced range in your example.

        1. What you don’t say :-) I wrote this just to illustrate the effect. Sampling 38kHz with 32kHz also gives you some mixing/intermodulation products. Or did Sony use 36kHz, I am not quite sure any more. But I am quite sure they used a different carrier frequency than the widespread (e.g. Philips) RC5 coding, for which you could get the integrated receivers like TSOPxxx most easily. It was also a different encoding scheme. Not Biphase-mark/Manchester, but something with 1,2ms and 2,4ms representing 0 and 1. I am not sure any more if this times were burst length or pause time. It was >20yr ago, that I investigated this.

      2. I used the same HP48SX software in a math class back in ~1992… The TV went on, then as the teacher walked over, it turned off. Teacher went back to the blackboard, TV went on again…. the teacher then unplugged it…

      1. Search google: tennis world speed record

        the answer: 163.7 mph (263.4 kph) (apparently)

        [Source]

        Possible, but practical?

        Carrier-less IR systems would likely allow this. However Those must be some dayaaamn cheeeeeep TVs.

        .
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        PS I only use a (Tuner removed) TV as a computer monitor for it’s size to viewing distance ratio.
        I only heard of ancient aliens on history channel because of a debunking video (a very factual one at that matter) that I came across in an unrelated search. (I just don’t watch TV, I get my news from papers+alternative sources: Esp when backed by video and looks genuine without dispute or otherwise).

    1. Except that you need a carrier, and the data. This code is also far too short to contain a full header and command sequence, let alone a carrier. You would need a long reel of paper travelling rather quickly to achieve this result.

      The big giveaway is the “Universal Standby” nonsense. No such thing.

    2. The right speed is essential to get the timing of the low-speed serial bitstream right, regardless of the carrier frequency.

      Suppose we use a small 800nm laser diode. Don’t use a LED, because we want to switch off the light with a sharp edge, not a curve as the tape edge passes through the beam.

      Now apply the carrier modulation at the right frequency.

      Now is it plausible? Well maybe, only if the tape moves at the right speed.

  6. All IR remote receiver ICs have dedicated silicon at the phototransistor for the express purpose of looking for the carrier at the correct frequency and demodulating it. It’s fake.

    By the way, an infrared LED is ~ 800nm, the thermal infrared (like the blackbody radiation spectrum of a flame) is ~ 10000 nm.

  7. That’s a nice hack!

    It could definitely work (in some special conditions).
    I powered a TSOP1730, and its output can be triggered by a lighter and some moving paper slots. Not very reliable/repeatable, but it can be triggered without a carrier. Also, there are some other things that may be tricky, like the RC-5 toggle bit and so on, but it might work.

  8. I was thinking about how to improve this hack…
    First the lighter could burn the paper sheet, so it should be replaced by an IR led.
    Then to get a better modulation and a more reliable result, we could replace the paper sheet by a simple electronic modulator (arduino ?) and a push-button to switch it on/off easily.
    Finally put all that inside a small plastic case, and while we’re at it, add some other buttons to get some more commands like channel up/dn, volume up/dn and so on.
    I’m pretty sure this can be done in the near future !

    1. There were even devices with an arduino in it, called TV-be-gone. And regarding the average TV program, they are much more useful than a normal remote, which can only defeat one type of TV.

  9. It looks bit fishy to me.

    1) No carrier … makes me wonder how is that possible without carrier. May be candle emits very strong IR to force detectable levels of signals into passband. But very unlikely.

    2) Last shot is one single shot. They say, you have to get the timing right. The video shows that the demonstrator does it very flawlessly. I can understand there could be many retakes, but this is single shot from start to beginning.

  10. Saw a presentation once by a guy who had a large circular card mounted in a power drill. Holes punched at various locations in the card such that he could shine a flashlight through the holes, pointed at some sort of photo receiver, with a bit of circuitry to convert light to sound, and play Reveille.

  11. Unfortunately it is a fake video. :( Yes it is faking TV remote.

    It is impossible to do this. I have a decent enough experience playing with IR remote emulation and decoding. A modulated receiver cannot do false trigger for the entire message. I agree it can trigger for false signal but not do the entire message.

    Another thing is that the message cannot be easily replied by hand movement. The RC5 timing is little bit critical, we cannot simply stretch or compress the message by human error.

    So I believe this is a fake video until or unless some one tries it and proves it is correct.

    1. Sadly we live in times when nothing can be conclusively proven to be bullshit anymore. Back in the day they were quite aware of this problem which is why the one making an assertion tended to need to prove it before it meant anything – this particular requirement has been greatly relaxed since, unfortunately…

      1. Nah, bullshit is still bullshit. There are two problems. One is that liars are more brazen and shameless. The second is lazy “journalists” who haven’t investigated anything in generations.

        Oh and also people aren’t that smart, but that’s always been the case.

  12. they had me too until i read universal remote code, but only for power-button. i was all like: “what? tv-b-gone design (brand&model lookup table) was all in vain because there is a secret code that works for all tv’s?”

    … the creators of this might have forgot that SOME people have been studying this for ages as it is totally ubiquitious, old, affordable, and hackable.

    uuunless his specific tv has a glitch where an invalid signal locks it up, and it re-starts (in off mode), but that would be the opposite of universal, more like “for model XXX-x.x” so im still calling fake until the content is voluntarily changed from “universal-tv-code” to “code-for-MY-tv”

    FYI: tv-b-gone works by spitting out all codes known to the author, one after the other! looks like someone that doesnt like/understand tv-b-gone and is hoping they are correct that there exists a secret code we dont know about, and somehow the entire internet will praise him for discovering something that only exists in an infectious-viral-load-of-… maybe the universal-code part was you getting virus’d as you clicked “this one-weird &amp special link_&?ref=gs”

    1. My VHS had a glitch: When I used a universal remote and accidentally pressed the key which switched the TV to AV-input in the VCR mode of the remote it generated an undocumented signal which made a factory reset on the VCR – all memory lost.

      1. true or not you made my day!

        you reminded me of the movie/show Kevin Spencer, episode where the hacker got out of jail from dialing a string of numbers on the payphone, kevin meanwhile was only able to get the toilet to flush XDXD

  13. Though you know what, old Sony remotes will turn off a heck of a lot of TVs, had one for a a betamax and TV mode, the power off worked on 7 different TVs, panasonic, RCA, hitachi ….

    1. Sure. I have even more anecdotal evidence: Back in the early ’90s, our family TV would switch channels or turn off if the sun hit it at a certain angle. Our solar system’s yellow dwarf is the OG TV-B-Gone.

      This is a modern TV though. And nowadays, even TVs from one and the same manufacturer would oftentimes require different codes. I doubt that the cutout code even works with the TV in the video, a Philips brand, because the cutout pattern doesn’t look like RC5 or RC6 to me (but I’ll happily stand corrected on that).

      1. I had it down as some legacy mode support for remotes that were among the first common ones in the 80s.

        I mean officially the TV would have a native command code for every function, but also recognised some subset of older remote commands.

        It turned 7 off, but on one non-Sony, the channel and volume worked as well as power on and off.

  14. This is a great hack, Here is my take on where to go from here.

    Transmitter/Receiver
    Have reels of paper and a whole punching machine, The whole punch machine is attached to a controller or computer by serial, You send commands the paper is punched then the IR is emitted as the paper goes on by in front of a lighter. So you have two of these set up in line of sight both with an IR receiver module. Come on let’s see if someone can transmit the Hackaday Retro edition website (-pictures) to the other one to display on a little TFT that isn’t connected to the internet.

    1. If someone pulled this off It would have to be in the Hackaday hall of fame. I don’t think anyone has used hole punches never mind IR detecting hole punches to load the hackaday retro (-pictures) website.

          1. I have a Palm Tungsten E2 that can connect to the Internet via Bluetooth to another device. I wanted to add a dial-up modem to the chain, but a Rube-Goldberg IR setup is much better IMO. I wouldn’t learn anything besides writing a few scrips with the dial-up modem.
            I have to search for some suitable old printers…

  15. There are several problems with this idea: First, the light source is too broad compared to paper slices, so the shadow on the IR receiver TSOPxxxx is too blurred to distinguish between mark and space. Also, there is no 38 or 40 KHz carrier. Maybe some old types do not use modulated signal, but new TVs surely need it.
    So, the only way to switch off TV with lighter and paper is to lit a paper and throw it in your TV set. Yes, you will need the fire extinguisher also.

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