The `!LILYGO T-Echo`! is a device based around the nRF52840 microcontroller and the SX1262 LoRa transceiver.

>>Contents

• `F0af`_`[Models`#models]`_`f

• `F0af`_`[Firmware`#firmware]`_`f

• `F0af`_`[Bootloader`#bootloader]`_`f

• `F0af`_`[References`#references]`_`f

• `F0af`_`[External links`#external-links]`_`f

>>Models

The T-Echo comes in two variants. One features a LoRa module labeled with `*433/470`*, while the other is labeled with `*868/915`*. While these labels indicate the approximate frequency ranges they operate on, the exact supported ranges are not listed.

There is also an upgraded model, known as the `!T-Echo Plus`!, which features a larger 2400 mAh battery. The T-Echo Plus comes in both frequency variants.

>>Firmware

The T-Echo is supported by the official `F0af`_`[RNode`:/page/wiki.mu`path=RNode]`_`f firmware as of version 1.81.`:cite-ref-1[`F5bf`_`[1`#cite-note-1]`_`f] It is also supported by the `F0af`_`[microReticulum`:/page/wiki.mu`path=MicroReticulum]`_`f firmware as of version 1.86.4.`:cite-ref-2[`F5bf`_`[2`#cite-note-2]`_`f]

>>Bootloader

The original bootloader that comes flashed to the T-Echo works fine for most use cases. However, to enable OTA firmware updates, the OTAFIX bootloader can be flashed to the device instead. This allows for the device's firmware to be updated over Bluetooth.

>>References

`:cite-note-1`!1.`! `F0af`_`[↑`#cite-ref-1]`_`f "Release 1.81".

`:cite-note-2`!2.`! `F0af`_`[↑`#cite-ref-2]`_`f "Release 1.86.4".

>>External links

`!Official Store`!

• T-Echo

• T-Echo Plus

`!Official Wiki`!

• T-Echo

• T-Echo Plus

>>LILYGO T-Echo

`!Manufacturer:`! LILYGO

`!Type:`! Mobile device

`!Price:`! US$49.11

`!MCU:`! nRF52840

`!CPU:`! Cortex-M4 @ 64 MHz

`!Memory:`! 256 kB SRAM 1 MB Flash (On-chip) 2 MB Flash (Onboard)

`!Display:`! 1.54-inch E-paper 200 × 200 px

`!GNSS:`! L76K

`!Power source:`! 5 V USB Type-C 3.7 V 850 mAh LiPo

`!Dimensions:`! 127 × 53.8 × 24.3 mm

>>>Bluetooth LE

`!Transceiver IC:`! nRF52840

`!PHY modes:`! 2M, Coded

`!Output power:`! 8 dBm (6 mW)

`!Sensitivity:`! -95 dBm @ 1 Mbps

`!Antenna type:`! SMD Ceramic

>>>Sub-GHz LoRa

`!Transceiver IC:`! SX1262

`!PHY modes:`! FSK, LoRa, LR-FHSS

`!Frequency range:`! 433/470 MHz or 868/915 MHz

`!Output power:`! 22 dBm (160 mW)

`!Antenna type:`! External SMA