## What Does It Do? **WebJack is a wired, bidirectional data link between the Arduino Uno and your phone, established via headphone jack.** It uses two distinct frequencies for a modem-like serial transmission of data. WebJacks runs in the browser and its goal is to provide a way to read sensors without the burden to install native applications. Look for recent updates on Public Lab [here](http://publiclab.org/tag/webjack).  ## Activities This is a list of community-generated guides for specific applications and the development of WebJack. These [activities can be categorized](https://publiclab.org/wiki/activity-categories), and some may be more reproduced -- or reproducible -- than others. Try them out to build your skills, and help improve them by leaving comments. Together, we can repeat and refine the activities into experiments. ### Activity grid [activities:webjack] **** ## Frequently Asked Questions Ask a question about WebJack [notes:question:webjack] **** [](//i.publiclab.org/system/images/photos/000/017/089/original/IMG_0138_web.JPG) WebJack is an open source client-side JavaScript library that acts as audio modem. It is built for use with [SoftModem](https://github.com/arms22/SoftModem), the Arduino-side code. For example, with WebJack you can transmit: * data as text * binary data * Firmata RPC messages *** ## Challenges We're working to refine and improve WebJack on a number of fronts; here, take a look at the leading challenges we're hoping to solve, and post your own. Be sure to add: * constraints: expense, complexity * goals: performance, use cases [questions:webjack-challenge] **** ## Build a data link with WebJack Instructions on the circuit and software needed for WebJack can be found here: https://publiclab.org/notes/rmeister/07-18-2016/webjack-testers-needed ### Demo WebJack applications - [Using Firmata with WebJack as transport](https://publiclab.github.io/webjack-firmata/example): - [WebJack demo website](https://publiclab.github.io/webjack/examples) ###Notes: - For more information about WebJack, post a question to the "dev" mailing list [here](https://groups.google.com/group/plots-dev)) (also listed in the left sidebar) - The github repo of WebJack is [here](https://github.com/publiclab/webjack) ...
| Author | Comment | Last activity | Moderation | ||
|---|---|---|---|---|---|
| warren | "warren awards a barnstar to rmeister for their awesome contribution! " | Read more » | about 8 years ago | |||
| warren | "This is tremendous work, thank you Richard. Some possible next steps would be: making (or creating a clearly documented issue for) on-the-fly se..." | Read more » | about 8 years ago | |||
| warren | "That makes sense. I hadn't been able to find a pinout for the Chromebook, but i'll order that and try it out. " | Read more » | over 8 years ago | |||
| rmeister | "According to the first review on Amazon the pinout of the cable is (from tip to sleeve): Left (white) Right (red) Video (yellow) Ground But as..." | Read more » | over 8 years ago | |||
| warren | "Odd -- the microphone seems to have been running along with the input. " | Read more » | over 8 years ago | |||
| warren | " My_recording__1.wav " | Read more » | over 8 years ago | |||
| warren | "Here's a good resource on many plug standards: http://connector.pinoutsguide.com/4_pin_3.5mm_2.5mm_plug/ But it seems that tip and ring 1 are usua..." | Read more » | over 8 years ago | |||
| warren | "Hmm, i received the two cables I mentioned, but it wasn't recognized as a microphone when I connected them, either in Red-Yellow/Yellow-Red or Whit..." | Read more » | over 8 years ago | |||
| rmeister | "Right, that should be inlcuded in the readme. Yes, echoCancellation is disabled at quiet.js: https://github.com/quiet/quiet-js/blob/master/quiet.j..." | Read more » | over 8 years ago | |||
| warren | "Ok! Would it be possible to mention this stuff in the readme? Have you had a look at quiet.js? Do you think they disable echoCancellation? Thanks! " | Read more » | over 8 years ago | |||
| rmeister | "Sure, but anything above 7kHz will need disabling echoCancellation. gh-pages is currently set up with 2450 and 4900 Hz, echoCancellation active. F..." | Read more » | over 8 years ago | |||
| warren | "Ugh, sorry -- i posted my Leonardo test in the wrong place -- here: https://publiclab.org/notes/rmeister/07-18-2016/webjack-test-without-arduino#c1..." | Read more » | over 8 years ago | |||
| warren | "Wait, though -- can we change frequencies in JavaScript instead of SoftModem.h? Much easier, no? https://github.com/publiclab/webjack/issues/26 " | Read more » | over 8 years ago | |||
| warren | "Ugh, oops. I'll move the comment -- had to use someone else's computer which has a non-combined headphone/mic port, so I was hurried logging in and..." | Read more » | over 8 years ago | |||
| rmeister | "@warren this is the tutorial for testing without Arduino :) Signal looks fine though. Remember to change the frequencies in SoftModem.h " | Read more » | over 8 years ago | |||
| rmeister | "That could work. But you will need an additional adapter for every device with AHJ pinout: https://www.headsetbuddy.com/3-5mm-ctia-to-omtp-smartpho..." | Read more » | over 8 years ago | |||
| warren | "I tried again (after this attempt) and turned down the audio gain, but still didn't receive on the gh-pages demo. It doesn't look blown out: H..." | Read more » | over 8 years ago | |||
| warren | "I'm thinking about how we might add some hints for how to most easily do browser-to-browser over a cable. Just an idea -- what if we used these two..." | Read more » | over 8 years ago | |||
| liz | "Wow a real milestone! " | Read more » | over 8 years ago | |||
| rmeister | "Leonardo is again a different processor with different names for the timers used in the library. I think we can fix that with some #ifdef's in the ..." | Read more » | over 8 years ago | |||
| warren | "Hmm, the Leonardo also failed to compile with similar errors to the ATTiny -- odd; I wonder if there's something wrong with my setup in general... ..." | Read more » | over 8 years ago | |||
| warren | "I also have a Leonardo I can test this out on, I'll dig it up. " | Read more » | over 8 years ago | |||
| rmeister | "Cool, thanks for your effort! " | Read more » | over 8 years ago | |||
| warren | "Oh, cool! I heard that "dimming" occur when I piped the sound through a small amplifier, but didn't know it was supposed to be that way. Neat. Than..." | Read more » | over 8 years ago |