iPhone-based universal IR remote

If you have a reasonable home theater setup in your living room, odds are you have up to half a dozen remotes sitting around. Short of trying to get your cable receiver’s remote to control everything or laying down some cash for a Harmony remote, what’s a hacker to do?

[Andrey] decided he wanted to use his iPhone as a universal IR remote, but he didn’t want to pay very much to do so. Instead of buying a dongle at the store, he soldered some IR LEDs to an old headphone plug, creating a mini IR dongle to control his equipment. After studying IR signaling a bit, he got to work encoding IR remote commands into wav files using Python. The files are then played on his iPhone, allowing him to submit certain commands to his TV set.

Unfortunately, the process of manually converting IR codes to audio files doesn’t quite seem like the most efficient way of doing things. There are other IR dongles currently on the market that utilize the headphone jack, most of which provide pretty robust software for free. These might make a good alternative to manually creating audio files for each IR command. We honestly haven’t seen any teardowns of these retail IR dongles posted online, but it would be interesting to see how they compare to what [Andrey] has put together.

28 thoughts on “iPhone-based universal IR remote

  1. I see no reason why this is ‘iPhone’ based.
    It should work with any device with audio out that can play wave files. Or did I miss something?

  2. Can’t you get the remote apps for other inferred dongles for free? Since they usually just charge for the dongle. Would it be posible to use those apps with this?

  3. this looks interesting for $20. much cheaper than the other options ive seen.

    http://ryzmedia.com/

    honestly, buy a monster AVL300 (harmony 890 PRO clone) and be done with it. a much more robust and complete solution for single remote control of just about everything under the sun. plus, you dont have to use an/your iphone. they can be had with RF-IR blaster box for $68 online.

  4. In that article back in 2004 they used Griffin Total Remote. It’s currently discontinued, otherwise I’d be very interesting in dissecting it and finding how do they boost signal.

    The interface in this hack is sure bogus, but I wanted to see if there is an interest in such a remote at all before spending more time to improve it. It looks like there is interest and soon the UI will get better.

    Those universal remotes are not as good as you may think – I have one and it’s far from being perfect. iPhone with its huge (comparing to Harmony) touchscreen and internet connection would make a much better remote.

    And yeah, it is not iPhone-based, here is youtube video explaining this: http://www.youtube.com/watch?v=sYOBIhcP2Yc)
    and the project webpage: http://www.rtfms.com/episode-4-turn-your-iphoneandroid-mac-pc-player-etc-into-a-universal-remote.htm

    I tested it on iPhone only though and currently trying to test on Motorola RAZR, hope it will work fine.

  5. I wanted to do this some days ago but then found out the voltage for a single channel was too low on my iPhone (was ok on my iMac though). I didn’t realize you could combine the channels for double the voltage xD

  6. Sweet, I was just looking at some of these hacks from way back when. In answer to someone else’s question, the other remote apps don’t work unless you have the legitimate dongle. You have to enter in a serial # in order to get it to work together. The app is free but it won’t do anything without the hardware.

    I need to check out My TV Remote app that durfdee just posted. It looks to be more promising. Anyone know if I have to buy specific wavelength of LED or can I just grab a couple from an old remote. What kind of voltage actually comes out of the headphone jack when turned up all the way?

  7. @Jammin0

    The wavelength of the LED is far less important than getting the carrier frequency as close as possible to what the receiver is expecting (depends on the brand/protocol being used). So, in general any IR LED should work.

    Regarding the voltage present at a headphone jack, that varies quite a bit from device to device, because there really isn’t any hard standard for this.

    In my experience, most portable devices will output between 1 and 3 volts AC (peak-to-peak) at full volume.

  8. 940 to 950 nm is what remotes use. The receivers are most sensitive at that wavelength. Using a 830 to 890 nm LED will significantly reduce range in a low power application like this.

  9. @Nth

    Thanks for the info. I got millions of old remotes lying around my workbench. I live right by a Goodwill outlet where you buy stuff by the pound. Pretty much every time I go I pick up a few old Comcast remotes. Most of these usually have 2 LEDs and they should be a perfect match to each other.

    I can’t wait to do this when I get home from work. Should be able to have it up and running in 15 minutes.

  10. To drive IR LEDs through a WAV file is a really good idea! I never thought about that!
    Do you think that is possible to collect (almost) all TV power off signals to create a sort of TV-BE-GONE.WAV?
    In that way every old mp3 player could be used to power off TVs, that is a wise thing.

  11. As the guy who actually invented this technological concept back in 2001 I am always highly gratified, and somewhat amused, to see that it is still going strong. Good job, guys!

    –Don Stratton,
    –Former Griffin drone and creator of Total Remote

  12. Much easier and cheaper: use an old Palm unit. There are multiple applications which take advantage of the already-installed IR capability of all the classic Palm devices, along with their graphics capability, to replace remote controls. http://download.cnet.com/SecondScreenTV-Remote/3000-2094_4-10204437.html

    http://download.cnet.com/OmniRemote/3000-2094_4-10024126.html

    http://download.cnet.com/NoviiRemote/3000-2056_4-10188050.html

    http://download.cnet.com/ProntoLite-for-Palm/3000-2056_4-10146695.html

    http://download.cnet.com/Palm-Remote/3000-2094_4-16809.html

    After all, we all have a bunch of these things lying around, right? Put them to use….

  13. @oPossum

    Thanks for the TBG. Do you have by any chance the same files with 44.1kHz samplerate? These are 48kHz and many devices do not support this rate. I don’t have a Windows computer loaded with compiler at the moment and can’t recompile and regenerate the files.

    Thanks again!
    Andrey

  14. This is a cool trick! I am also interested in the lower level theory of the IR, since I have a PDA which just sits on the dock. It has consumer IR and I’d like to make a universal remote out of it without 3rd party software, more as a learning exercise. However, I got blocked on my learning, due to the unknown of how to map a frequency to writes out a com port.

    Unsure which baud I should set and how to correlate the ‘learn’ function of reading off the COM port and mapping it to time/frequecy in order to write the same code back out which should then activate the appropriate remote function. Anyone have any good experience or tips on this? I have done the google searching and came up short of getting to where I need to be. Thanks!

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s