Build an Off-the-Grid Wi-Fi System for Voice Communications [Tutorial]

June 5, 2020 by 50 Comments

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Cyber Weapons Lab, Episode 163

It can be difficult to communicate off the grid when there’s no infrastructure. That’s also true when you’re in situations where there is no cellular service or reliable Wi-Fi hotspots, such as a convoy of vehicles that want to talk to talk to each other, or protestors around the world where law enforcement cut out the cell signals. On this episode of Cyber Weapons Lab, we’ll show how you can use a cheap $35 Raspberry Pi with PirateBox to enable Android phones to talk to each other without using any cell towers.

To learn more, check out the article:

PirateBox Setup Video:
Picking a Wi-Fi Antenna Video:

Raspberry Pi:
Alfa Tube-U:
Flash drive:
MicroSD card:
Card reader:
Power supply:
Ethernet cable:

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50 Replies to “Build an Off-the-Grid Wi-Fi System for Voice Communications [Tutorial]”

  1. annonymous says:

    Kody did you work in any movie?

  2. Haudiweg says:

    your audio is bad (constand sounds)

  3. Nabil says:

    Thanks for this amazing tutorial! what is the music used in the background?

  4. Roxas13XIII says:

    I'm not sure how far in advanced this was recorded, but I was able to use my raspberry pi 4 with berryboot to get PirateBox working. I used the image from here:

    The biggest issue I've had so far with the raspberry pi 4 is getting Kali to work correctly. Getting it from the official site doesn't work for me (keyboard/mouse input doesn't work) so I've had to use the Sticky version, which still has a problem because if I run sudo apt-get upgrade, it breaks the OS for whatever reason.

  5. Said Farisi says:

    Couldn't you just use a wifi access point, connect all the devices to it, and then use the app to communicate !!

  6. Píchass says:

    How would you do this on a beaglebone?

  7. jay1o1o says:

    my fav offline apps APP 1) wifi talkie (talkie for short) for andoid connect to wifi, send files,private message,group voice by calling everyone by clicking on name, share app offline via bluetooth comes with apk off app store ..APP 2)walkietooth one on one video, voice, and audio by wifi,wifi direct,wifi hotspot,bluetooth all offline …APP 3)Briar encripted text messages sync up over wifi, bluetooth, and tor network . download the apk off briar sight and share offline.

  8. RodCornholio says:

    Reinvented the walkie talkie (voice only) – arguably making it worse in terms of range.

  9. Sandesh says:

    That antenna hes holding looks like a wand

  10. Bist du Deutscher oder Österreicher?? Warum steht da sonst "ist das system relevant"?

  11. david ruso says:

    please never stop making videos man, you are truly amazing !

  12. That cattle prod worries me.

  13. Hi There says:

    Doing things the hard way is cute …. but why?
    You already had a router. Why you just didnt add the externeal antenna?
    Or why not to take on Mikrotik Router board for 20.- EUR and add external antenna?

  14. Monde Grune says:

    I just used this system and now i have a plane parked in front of my home 🙀

  15. Logic Bob says:

    Wait, wait, wait! "sudo !!" reruns the previous command with sudo? 😳

  16. Agha Seyed says:

    Next video could be OPEN WRT …. ;))

  17. deeeeeerp says:

    A very timely video. What are the limitations on the number of devices/amount of traffic this setup could handle? the wireless adapter or the pi?

  18. Your distance isn't going to be that far and you are still line of sight..

  19. Frosty Bros says:

    Yo @NullByte couldn't you download the Mumble server before you take the Piratebox offline and have a Murmur client on both phones? Text and talk client. Just guessing haven't done any testing but working on assumptions. If anyone has tested please let me know your findings.

  20. klyper says:

    At least I’m not the only one riding 10% battery

  21. WAL says:

    I'm searching a starter ethical kit.. any ideas?

  22. Got a link to the ali version of the Alfa Tube-U you have? Would like to demo it on some cheaper stuff first before I commit to an Alfa off the bat

  23. supadubz says:

    Thank you for this, it will help a lot with what’s happening now. Deploying communication systems in nyc

  24. You voice is soft as silk. I love silk. 💗 I would love a tutorial on getting into an iphone " without " using social engineering or needing user interaction.

  25. DarkKokoro84 says:

    When will the image be aval for the Pi 4?

  26. Ian MAN says:

    Are you working at home because of COVID¿

  27. Kevin Hughes says:

    Just bought your premium bundle and I'm already having fun with it, thanks for the deal!

  28. JunkBoi76 ! says:

    Your vids have taut me more than my computer class in a year thanks

  29. Sorry man i cant past the minute and half due the background noice you have there.

  30. Rodrigo Boos says:

    Check the Serval Project: "The project aims to develop technology that can be used to create direct connections between cellular phones through their Wi-Fi interfaces, without the need of a mobile phone operator. The technology allows for live voice calls whenever the mesh is able to find a route between the participants."

  31. Martin W says:

    Im going to throw LoRa Mesh Chat into the room

  32. 7curiogeo says:

    Sounds like a good trick. I am old school and keep thinking why can't I voice link to another phone, for voice instead of data?
    I know I don't know, the tech is just beyond me.
    I just use cb or FRS with security protocols. It works.
    But every one has a phone now, so cool idea. I think.

  33. Chaos Wizard says:

    Wait a minute off the grid but on the wifi? How's that work?

  34. AK27M says:

    what is the range when using that external antenna

  35. Not sure why you need such complexity, but there are apps on the same Play Market that can let you communicate with others (provided they also have that app open) i.e. text, voicechat, share files and creare rooms.

    Remember doing it 7-8 years ago when I was in a camp with no wifi and none of the ppl had cellular network with unlimited trafic (was pretty uncheap in my country). Thankfully one guy brought a wifi transiever in hopes of using someone else's wifi (we did cought one with 1-8 password but signal was REALLY poor). So what we ended up is downloading some app (using that wifi lul), sharing it with BT and using it all day (and night).

    Pretty sure you can use a regular wifi router for such purposes

  36. benny s says:

    It's funny how these folks can do wonders, but a simple web GUI isn't one of them.. Too much typing sudo shmoodo, just make a damn GUI you can connect to like a normal router :

  37. EOD MEDIC says:

    Man the things in my suggested sure seem to be affected by current events lmao

  38. Nice video, but I do hope you can get rid of the distortions.

  39. That is a nice project, but really for a Rural/Hiking situation, you'd probably be better off with a Walkie Talkie (Radio) and with a free APP you can view your GPS location Coordinates (without need for cell phone signal)

  40. Lord Samich says:

    Call me a cynic, but I'm reasonably sure you can build an 'off grid' voice communication system without an Arduino / raspberry whatever.
    If anyone's interested have a roadrunner VHF for sale.

  41. Lord Samich says:

    +Null Byte

    Have you looked into codec2?

  42. CR Solarice says:

    I like it but… CB probably cheaper and do a 1kw linear amp and you can probably get coast to coast….

  43. gaby1491 says:

    or buy walkie talkies

  44. Thank you so much man, I have been watching your videos since 2 years ago, I have learnt so much and you have motivated me so much, I’d love to keep learning, keep it up man!

  45. r00t hkr says:

    His computer says "come back with a warrant", but $10 says he's running either Windows (but probably not) or Mac OSX (clearly he is). You care about security but you trust your data with, literally, the bigges proprietary giant in tech?!?! Yeah, real secure. If you really cared, you wouldn't be using Mac or Windows.

  46. MStrickkk says:

    Love it. Now try to tie this into a hamnet system for super long range 😀

  47. Hey guys i really need help. Ive been dealing with this for 3 months. I haven’t had any luck. Someone has put a digital tracker on my home network. Some kind of digital auto logging tracker. My MacBook crashed my asus laptop crashed and in the last month I bought 2 computers just so i could build a flash drive to save my others. Within a day both of those computers have been breached. I’m on my second one right now and i shut it down quick enough. Ill pay $$$$$$$. This isn’t a joke and i would not be making this message. I’m sorry to spam you guys by putting this on so many videos. I really need help though. Contact my YouTube and ill give a email or phone number. I would be so grateful. I’m just trying to help society out like you guys. Giving knowledge big corporations and others don’t like.

  48. Bryett Dylon says:

    Would this work on pi4