Maker Eric Nam has showcased the clever off-grid communications capabilities of an open source project, getting a LILYGO T-Deck handheld to talk to an Apple iPhone using a Meshtastic mesh network — no cellular signal required.
"Meshtastic enables decentralized, off-grid communication based on LoRa," Nam explains of the open source project, which aims to turn any device with a LoRa-capable radio into an off-grid communication system. "By building your own network, you can do many things within it — such as controlling sensors as well as sending and receiving messages."
To demonstrate, Nam turned to two devices. The first is a LILYGO T-Deck, launched back in mid-2023 as a Blackberry-inspired portable development device based around the Espressif ESP32-S3 system-on-module (SOM) — which, by itself, lacks the LoRa radio required for Meshtastic use but includes a slot for an optional LoRa module. The second is an Apple iPhone, typically used on a commercial cellular network — and normally of little use if you're outside the network's coverage area.
"Since [the] iPhone does not have a LoRa module," Nam explains of how the devices communicate, "we must connect a module capable of LoRa communication. Here, I used a [LILYGO] T-Beam device. So, my iPhone connects to [the] T-Beam through Bluetooth. I installed Meshtastic's firmware to [the] T-Beam and T-Deck. After installing [it], you just need to configure a few things and you are ready to use it."
Nam demonstrates the point-to-point communication capabilities of Meshtastic, which have been proven to ranges well in excess of 100 miles when paired with suitable hardware, though that's only half the story: the system also supports true mesh networking, allowing messages to be broadcast to multiple devices or routed through an ad-hoc network of receivers until reaching their intended destination.
Nam's full demo is available in the video above; the Meshtastic firmware is published to GitHub under the reciprocal GNU General Public License 3, with more information available on the project website.