LILYGO T-Echo Meshtastic Node - nRF52840, 868MHz LoRa, 1.54" E-Paper, GPS (White)

Specifications

• Microcontroller: Nordic nRF52840 (ARM Cortex-M4, 64 MHz)

• LoRa Transceiver: Semtech SX1262

• Operating Frequency: 868 MHz (EU/India standard)

• Memory: 2MB Flash, 2MB QSPI RAM

• Wireless: Bluetooth 5.0 (BLE/Mesh), Thread, Zigbee, ANT, 802.15.4 (No Wi-Fi)

• Display: 1.54-inch SPI E-Paper (Black/White, 200x200 resolution)

• GNSS / GPS Module: Quectel L76K (GPS, GLONASS, BeiDou, QZSS)

• Battery: Internal 850mAh rechargeable Li-Po

• Power/Data Interface: USB Type-C

• Interaction: TTP223 Capacitive Touch Button (Back), NFC Sensor

• Dimensions: 66mm x 53.5mm x 24mm

Key Applications and Projects

• Meshtastic Networks: Acting as a primary, ultra-long-lasting portable text-messaging and GPS node for off-grid communication during hiking, skiing, or emergency disaster response.

• Asset Tracking: Attaching the device to vehicles, boats, or cargo containers to transmit location data over a private LoRaWAN network for weeks without needing a recharge.

• Glider/Aviation Telemetry: Utilizing the sunlight-readable display and GPS to show live flight data while broadcasting position to ground stations.

Unlock New Capabilities (Project Evolution) The Ultimate Mountaineering Relay: Because the nRF52840 is incredibly power-efficient, you can evolve this device into a permanent, self-sustaining mountain relay node! Open the ABS casing and connect a 5V solar panel to the battery charging circuit. Mount the T-Echo high up in a tree or on a mountain peak using a weatherproof enclosure. The solar panel will easily outpace the micro-power draw of the e-paper screen and nRF52840 chip. You now have a permanent Meshtastic router that significantly extends the communication range for your entire hiking group without ever needing to retrieve it for a recharge!

PACKAGE INCLUDED

• 1 x LILYGO T-Echo Unit (White ABS Enclosure, 868MHz version)

• 1 x 868MHz External Antenna

• (Note: Pre-installed with an internal 850mAh battery)

Downloads & Links

• LILYGO T-Echo Github Link
• LILYGO T-Echo Tutorial

FREQUENTLY ASKED QUESTIONS (FAQ)

1. What makes the T-Echo different from the T-Beam? The main difference is the processor and the screen. The T-Beam uses an ESP32 (which has Wi-Fi and draws high power) and an OLED screen. The T-Echo uses an nRF52840 (Bluetooth only, ultra-low power) and an E-Paper display, resulting in drastically longer battery life.

2. Does this device have Wi-Fi? No. The nRF52840 chip does not support Wi-Fi. It uses Bluetooth 5.0 (BLE) to connect to your smartphone.

3. What frequency is this specific T-Echo? This model operates on the 868 MHz frequency band, which is the legal, license-free ISM band for LoRa in Europe and India. Using a 915MHz version in Europe is illegal.

4. Can I use this for Meshtastic? Yes, the T-Echo is one of the most highly recommended devices for Meshtastic due to its incredible battery life. Ensure you flash the correct firmware-t-echo UF2 file.

5. How long does the battery last? Thanks to the e-paper display and the nRF52840, an 850mAh battery can last for several weeks to a month on a single charge under normal Meshtastic usage.

6. Why does the screen flash black and white when updating? That is the normal "refresh cycle" of an E-Paper display. It physically moves microcapsules of black and white ink to draw the image. Full refreshes (2 seconds) prevent "ghosting" of previous images.

7. Is the screen backlit? Can I read it in the dark? No, E-Paper displays are not backlit. They rely on ambient light. While they look amazing in direct blazing sunlight, you cannot read them in pitch darkness without a flashlight.

8. What does the touch button on the back do? There is a capacitive touch button (TTP223) located on the rear of the device. In Meshtastic, touching this button typically cycles through the different display pages (Nodes, Messages, GPS status).

9. How do I turn the device on and off? There are physical buttons on the top of the device. A long press on the power/reset button will turn the device off.

10. What is the NFC feature used for? The device has an NFC coil near the back. If programmed to do so, tapping an NFC-enabled smartphone against the back of the device can trigger an immediate screen refresh or transmit a paired payload.

11. How do I charge the battery? Simply plug a USB Type-C cable into the bottom of the device and connect it to a standard USB wall charger or computer.

12. How do I update the firmware? The nRF52840 makes this incredibly easy. If you double-tap the reset button quickly, the T-Echo mounts to your computer as a USB flash drive. You simply drag and drop the new .uf2 firmware file onto the drive!

13. Does this device support MeshCore firmware? No. MeshCore generally requires the Wi-Fi capabilities of an ESP32. The T-Echo is strictly for LoRa mesh protocols like Meshtastic.

14. My GPS is not getting a lock. What is wrong? GPS signals cannot penetrate concrete or metal roofs. You must take the T-Echo outside with a clear, unobstructed view of the sky. The initial "cold start" lock may take up to 5-10 minutes.

15. Can I change the antenna? Yes. The provided antenna connects to a standard SMA female port on the top of the housing. You can easily unscrew it and attach a higher-gain 868MHz antenna for better range.

16. Is the white casing waterproof? No. While the ABS plastic case protects against bumps and drops, it is not IP-rated or sealed with gaskets. It will not survive heavy rain or submersion in water.

17. What is the BME280 version I see online? LILYGO offers a variant of the T-Echo with an internal BME280 temperature and humidity sensor. Check your specific vendor listing to confirm if the BME280 is populated on your specific board.

18. Why does the screen still show an image when the battery is dead? E-Paper displays require absolutely zero power to maintain an image. Whatever was on the screen at the exact moment the battery died will remain permanently burned into the display until power is restored and a new refresh cycle is triggered.

19. How do I connect my phone to it? You use the Meshtastic app on iOS or Android and pair with the T-Echo using Bluetooth (BLE).

20. What logic voltage does the nRF52840 use? The internal circuitry and any exposed GPIO pins operate strictly on 3.3V logic.