World’s cheapest remote control replicator: just 1$ !
You won’t need anymore complex circuits & complex software to sample commands from your remote control and to replicate them; all you need is just two standard IR led, which you can afford for about 0.50 $ each, or maybe you can extract from a couple of old remotes.
This method was tested with a VIA AC’97 audio card; please report if you have any success with different cards.
What you need:
- 1 spare headphone cable (0$ if you already have it, 10$ if you need a new one)
- 2 IR led (0$ if you have a couple of old remote controls, 1$ if you need to buy them)

- audio recorder software, e.g. Audacity, opensource and multiplatform (Windows/Linux)
What to do:
3) Edit the resulting waveforms
5) “Replay” the waveforms:
a – Plug the emitter into HEADPHONE output of your audio card
b – Position the two leds just in front of your device
c – Press PLAY in Audacity: your device should react to the command you previously sampled.
NOTES:
1 – For unknown reason, playing the resulting signal in Audacity works fine to control my device; but if I save the signal into a WAV file and reload it in Audacity, playing it results in… nothing! Any explanation for this?!? FIXED: it was due to wrong carrier frequency of rebuilt signal, which must be HALF of the needed carrier frequency! (19 KHz for 38 KHz, 18 KHz for 36 KHz…)
2 – You can’t save the signal in OGG or MP3 format, because this format distort the original signal
Please report results of your experiments! Good or bad, please just report and share!
References and credits at bottom of this page:
http://www.planetmobile.it/jumpjack/LedRem/
Available patents (not mine):
Infrared generator from audio signal source
IR receiver using IR transmitting diode
[...] 4) Add an IR led to your recipe, and you obtain an SMS-controlled remote-control. [...]
[...] look at this post to know how to: – build an IR receiver for the PC – sample a remote control – (create a WAV file [...]
I’ve tried this and it worked great.
I have one question:
Can I save this as a WAV file or something so I can use an iPod for example to reproduce de signal?
PS:Sorry for my english
Sure you can use the WAV files on your IPOD: my idea actually started from a similar project… to turn IPOD into remote!
But please tell me if yout Ipod accepts these files, or if they must be in a different format.
(number of channels, sample rate, bits per sample, bytes per sample).
I tried it and finally works correctly.
Some remarks:
1. I must invert recorded signal.
2. Transmitter cannot work without a simple amplifier.
These issues due to my soundcard (Via on my mobo)
Recording with Ir led is US patented:
http://www.patentstorm.us/patents/6701091/description.html
Can you show the “Simple amplifier”.
This one looks good, as it also shows components specifications and names:

http://sci-toys.com/scitoys/scitoys/computers/solderless/amplifier.html
S5vi, thanks for your feedback.
Point 1) is a known issue, that’s way I updated my RAW2LIRC program in such a way it can “flip” the signal if required. Anyway, you can invert the sampling led to avoid this.
Point 2) is quite strange; I have a VIA AC’97 …
About patents: I knew using IR to play sounds was patented, not that recording IR through audio was too; anyway, anybody can use any patented technology as long as he does not sell it. That’s why patents are freely available online:
http://www.freepatentsonline.com/6931231.html
I should have added to credits, indeed…
I will, together with your link.
Hi, I’ve a really dumb question, but I’m more software than hardware…
I’ve looked on ebay for “IR LED” to gve this a blast, and I’ve got various specs like below:
Size: 5mm
Forward Voltage (V) : 1.5~1.6
Forward Current (mA): 60mA Continuous, 120mA peak for 10% Pulse Width
wavelength (nm):850
View Angle: 15-30 degree.
Does any of this, like the wavelength, or forward current, matter?
Will this mean that the range of the built remote will be affected?
fyi, my ‘big idea’ is to write a universal remote program to run on my kohjinsha UMPC, where you can associate buttons with sound files, and opensource it so I can:
1) Replace the 5 remotes I have
2) Add support into the mediacentre i’ve written
Cheers!
I have no I idea, I bought my leds in a store, just asking for “IR LEDs”.
Don’t you have an old remote no more working/used to get the LED from?
Hey,
(I hopefully won’t lose my PC any time soon!)
Nope no spare remotes…
If anything, I keep on losing remotes, which is why a computer based remote is a good idea
I’ll give it a try with the ebay bought LED’s (if anything I’ll only lose £1)
Cheers!
p.s. the instructions have been very useful: i read the ‘How-To Turn your iPod in to a Universal Infrared Remote Control’ on engadget, then was looking to buy the Griffin IR device, which looks like isn’t manufactured any more.
This article has made it possible!
[...] read a really cool (read geeky) article here where this dude made a universal remote control for $1 from a set of headphones and 3 IR [...]
i’ve try this, and its working fine.
i tried few more condition, with one or two LED and not used the ground cable, its still can working fine.
the question is how to export WAV audio file for playing in my PSP.
the AUDIO format only working in sample bit rate 96000Hz, thats can’t be save as MP3.
WAV with 96000hz bitrate can played on windows media player, but can’t recognize on my PSP
sory my english not good
MP£ wouldn’t work anyway, as it is a lossy compressione method which cuts just the needed frequency!
you should figure out if any WAV player is available for PSP, as WAV is the only uncompressed audio format, as far as I know; any compressd format wouldn’t do the trick.
THese FAQ appear to suggest that PSP does suport WAV format:
http://psp-download-center.com/faq.php
You could try this player:
http://forums.qj.net/psp-development-forum/103679-release-wav-player-psp.html
I think also lower frequency than 96000 Hz should work (try more typical 44100 Hz for example).
Please let me know if you do succeed in using PSP as a remote!
And, in case it works, some pictures would be cool!
hi,
i was very excited to find your guide !
i tried it to turn the TV ON/OFF, followed every step in your guide.
i used audacity.
recording was successful
converted “by hand” according to your instructions
when i play it (from the computer) using the emitter (2 leds with polarity reversed to one another), it does show the LED’s blinking bright in my camera, but when i bring it infront of the TV and play it does not turn on/off the tv…… i put it 1 meter away, and then closer and closer and closer to 5 Centimeters away, just didnt want to work.
i looked on 2 bursts consecutive burst sequences, and they looked the same so i converted only one of the bursts sequance.
i tried using a Sin wave, and a Square wave, just didnt work…
what am i doing wrong?
Can i show you my Audacity project files (that has all the recording and the conversion) ? if so where can i post it ?
thanks
please just send me your wav files (both original and hand-made), not the audacity project (it’s too large).
I guess you inverted the input led, anyway I have to take a look to your sampled signal.
please send to jumpjack at libero dot it .
it won´t work
1. record with audacity
2. use RAWtoLIRC
3. use LIRCtoledrem
4. start comand
5. play
My program is really rough, you should manually tune your signals to get proper results… or try usinh this brand new program an user just sent to me:
https://code.google.com/p/ledrem/downloads/detail?name=IR_Signal_Converter.exe&can=2&q=
(I didn’t test it yet)
[...] 錄製紅外線控制訊號的方式也很簡單,只需要使用一個紅外線LED。詳見老外"jumpjack"的"World’s cheapest remote control replicator: just 1$ !" 這篇文章(我也許會將它翻譯成中文)。 [...]
[...] It’s actually a “sound wave to infrared signal converter“. Before using it to control the NEX-5, you’ll have to “record” the IR signal and convert it into a sound wave. For more information about the IR recording process, please read this blog: “World’s cheapest remote control replicator: just 1$ !’ by jumpjack“. [...]
[...] but it’s pretty easy to capture IR signals as audio and later convert them back into IR. See this tutorial if you want to learn more about how this works and how to build [...]
Thx for this tutorial, it works after some problem solved. I used the program of jumpjack for reconstitution of the IR signal
1. record with audacity
2. use RAWtoLIRC
3. use LIRCtoledrem
4. start comand
And when i play the IR signal on my pc it works with windows player but not with winamp
Anyway gj guys ant thanks ^^
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