## 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). ![webjack-circuit](/system/images/photos/000/023/509/original/IMG_20180207_135242.jpg) ## 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] **** [![IMG_0138_web.JPG](//i.publiclab.org/system/images/photos/000/017/089/large/IMG_0138_web.JPG)](//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
rmeister "Wow, thanks @kinasmith! Probably this pulses are sort of a presence detection for the microphone? Could be an issue, but most of the signals from ..." | Read more » about 8 years ago
kinasmith "Just tested, didn't work. Phone: Xiaomi MI3C, MIUI 7.1.2 (Android 4.4.4) Component Values: R1, 2.2k; R2, 2.2k, C1, 2µF; R3, 10k. I also tried s..." | Read more » about 8 years ago
rmeister "A friend of mine just tested the demo site of the FSK generator with his iPhone (ios9.3.3). The script does not seem to work anymore :( " | Read more » about 8 years ago
dusjagr "@warren, i am referring to some barriers for connecting to iphones. conceptual barriers that can be circumvented exactly by this method. we use the..." | Read more » about 8 years ago
warren "Wow that's pretty exciting -- safari/iOS would be a huge feature to have. I'm wondering if folks are interested enough in this project to submit a..." | Read more » about 8 years ago
rmeister "Hi @dusjagr, thanks for that hint! Found a Safari compatible version of the FSK generator in your link section. At least sending data to the µC sho..." | Read more » about 8 years ago
warren "Oh, that's so rad, @dusjagr! Why are you keeping it from apple? The WebRTC lib doesn't work on iOS anyhow, since it's not an open platform, but jus..." | Read more » about 8 years ago
warren "Indeed -- maybe it could either just say "not safari or iOS" as https://spectralworkbench.org/capture does, or could specifically return an error a..." | Read more » about 8 years ago
dusjagr "Very nice! we have experimented with the same softModem library on the attiny85 for the same reason of an ultra cheap communication to send data to..." | Read more » about 8 years ago
rmeister "Hi Liz, thanks for your feedback! You can click on the photo to get a larger version. There the connections are visible more clearly. I'll see if I..." | Read more » about 8 years ago
rmeister "Oh, maybe I should add a note for iPhone and Mac users. According to this site, Safari does not support WebRTC yet: http://iswebrtcreadyyet.com/ " | Read more » about 8 years ago
warren "Huh, it's weird, but I could have sworn I clicked a link earlier and got http. But it seems fine now. I wonder what happened. Note to future selve..." | Read more » about 8 years ago
rmeister "Is there somewhere a link without https? " | Read more » about 8 years ago
rmeister "Cool, thanks for your results! Chrome Android → Chrome Android did work for me, but not very well. Sometimes I had to repeat sending like 10 times..." | Read more » about 8 years ago
warren "Oh, also -- for the WebRTC to work, you need to link to the https version of the Github Pages site -- because that's now required for audio access ..." | Read more » about 8 years ago
warren "I'm curious about the browser-to-browser use case, because as a SoftModem compatible protocol, we could also make this available as a general purpo..." | Read more » about 8 years ago
liz "Hi Richard, These are great instructions! I don't have experience to read the wiring diagram, and can't tell from the photo exactly what the signif..." | Read more » about 8 years ago
warren "I'm hoping to test with an Arduino soon too, but as a first attempt I was able to get "Hello world!" to transmit from my phone to my laptop with no..." | Read more » about 8 years ago
rmeister "Makes sense :) I'll go for the main discussion list first, probably with a research note, as pictures don't go well with emails. Then I'll work al..." | Read more » about 8 years ago
warren "I think that if you post on instructables, we should be sure there are clear ways to contribute, since you might get some good attention from folks..." | Read more » about 8 years ago
rmeister "Thanks Jeff! You are right, the explanation is rather short. And in addition to asking at the main discussion list, I had the idea to write an art..." | Read more » about 8 years ago
warren "Wow, some really impressive detective work here, Richard! Kudos. I should be able to do a test with my phone and Chromebook but am still traveling..." | Read more » about 8 years ago