How To Communicate Off-Grid Securely

Written By Matt Calhoun

The ability to privately communicate without using apps or centralized services is important, even if you are fortunate to never need it. I’m going to explain why, as well as present a couple of off-grid communication solutions.

Why You Need a Communication Plan

We are told on nearly a daily basis now that US communication systems and electric grid are increasingly vulnerable to outages and attacks. If a cell service outage lasted for several days or more, would you be able to remain in contact with nearby friends and family, or would that lack of service prevent you from staying in touch with people who are mere few miles away?

What are Your Options

I would avoid any option that involves reliance on mobile phones or PCs. Apps can be disabled any time, and modern OS’s are fragile. If you consider them to be loose-lipped AI spies personally assigned to you, you’re probably not far off.

A few good options for local off-grid communications include GMRS radio, amateur radio, and mesh communication systems. Avoid solutions that are centered around mobile phones/apps.

Voice Communication

Solutions that enable you to simply push a button and talk can be a perfect fit, depending on your needs.

Synchronous: Off-grid voice communication is going to be synchronous, meaning there has to be someone listening at the moment you are speaking, so communication needs to be coordinated and timed.

Never Encrypted: Encryption of voice transmissions over GMRS or Amateur frequencies is prohibited by law. This means, you are speaking to whoever is at the “other end”, along with anyone and everyone else who is listening on the same frequency. This may or may not be important to you.

General Mobile Radio Service (GMRS)

GMRS requires an FCC license, but it can be a good option for families. If one person in your family gets a GMRS license, that license may cover others in your immediate family using equipment.

  • Requires licensing, equipment, and setup

  • Range of 1 to 25 miles (can be extended with repeaters)

  • Communicating is fast and simple, get on the appropriate frequency and push-to-talk

  • Uses channels around 462 MHz and 467 MHz

  • Every other GMRS radio operator can hear you

Amateur Radio

This is such a deep topic I can’t even scratch the surface here, and I have much more to learn on the topic myself.

  • Requires licensing, equipment, and quite a bit of learning

  • Range varies widely, depending on knowledge, equipment, nearby repeaters, and what you’re trying to do

  • Extremely knowledgeable community and deep learning resources

Mesh Communication Systems

Off-grid mesh communication systems offer a much different approach to locally staying in touch with no grid services. I am the developer of ChatterBox, which is such a system.

Secure Off-Grid Comms Kit - Powered by ChatterBox

ChatterBox Features

There is much more to ChatterBox than I can list here, so visit chatters.io for a more in-depth look. Here are the basics:

  • Requires no service, mobile phones, cell towers, or internet

  • No App — This does not use your phone in any way. There is no app or modern OS involved at all.

  • No License Required — ChatterBox uses LoRa frequencies, which are not licensed like other bands (provided you stay within tx power limits)

  • Asynchronous — When you type a message, it works more like texting. The recipient does not have to in range or watching their device. In fact, the recipient’s device may be powered off. Your device will hold onto it and re-attempt delivery for up to 24 hours.

  • Encrypted + Signed — Every message and location transmission is encrypted and digitally signed

  • Meshing — If the recipient is not in range, your message will be “meshed” to other devices that have a path to the recipient. These other devices along the way will also store the message and reattempt delivery until the message expires.

  • Range is determined by how many devices you have, where they are placed, and what type of antennas (and/or amps) you have. The antenna on my own home’s roof transmits more than 10 miles for a single hop. Other trusted devices may pick up the encrypted message, and the question becomes how far can a message go before it expires (max 24 hours)?

Using ChatterBox

Designed to be easy to pick up and use, ChatterBox has a user interface that is probably similar to apps you’ve used, although it is firmware, not an app.

The ChatterBox T Deck firmware makes use of the touchscreen, keypad, and trackball of the T-Deck.

Mesh firmware home

Home Screen

This is the main view of ChatterBox communicator. You can view your sent and received mesh text messages, check on other devices, see which other mesh communication devices are nearby, and access your location off-grid.

mesh firmware device scanner

Neighbors Screen

Clicking the trackball or touching the Neighbors icon will take you to the screen shown below. Here you can see other devices that are within immediate range, access their location (if they’re sharing), and more.

mesh texting screen

Sending a Message

Messages can be secure broadcasts or direct messages. The screenshot below is for a direct message to “ali”.

Once sent, this message will work its way to the recipient (ali). It may be nearly instant if the two devices are within RF range.

If the other device is out of range or powered off, meshing will take over, and the packets will have up to 24 hours to reach “ali”.

mesh gps screen

Location Features

If GPS is on board (which is generally the case), you will be able to see your current location and heading (course over ground), as well as that of other trusted devices nearby.

Even with no internet or cell service, you can use this capability to see your position relative to others, and locate others. If their device is powered off or out of range, you can see and navigate to the last point their device transmitted from.

mesh secure remote control

Remote Control

This experimental (but now available) feature allows you to send secure mesh commands and queries to other on-cluster (trusted) devices, using the same mesh, encryption, and signature techniques.

You can query any device to see which other devices it currently sees, push/retrieve settings, and more, depending on the type of device.

Build or Buy

ChatterBox can be purchased completely ready to run, or you can purchase components from Amazon, Ali Express, or other sources, allowing you to build your own secure mesh communication system!

Get Your Backup Comms In Place

Whatever backup communication option you choose, get it in place and test it out before you need it. I recommend pursuing both amateur radio and secure mesh comms for maximum flexibility. An amateur radio license allows you to use voice as well as more powerful mesh equipment.

If others depend on you, it is irresponsible to wait until you actually need a backup system. We are told quite regularly that our grid is fragile and subject to outages & cyberattacks. If you wait until that happens, everyone else will need one, and you won’t be able to get it.

Without modern services fully functioning, something as simple as asking whether a store has milk or whether a family member needs something, without physically traveling to their location, can become impossible. Any of the solutions mentioned above can help you have a tool in your toolbox to deal with this.

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Matt Calhoun
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