Heltec CT62 (Capsule Sensor)

Heltec Automation

868 MHz 915 MHz SX1262 ESP32-C3 22 dBm
DIY Modules Budget

Ultra-compact Stamp module from Heltec based on the ESP32-C3 and SX1262. Only 10 µA deep sleep current. Designed as a development module (soldering required), but fully integrated into MeshCore Community firmware (Companion BLE/USB, Repeater). No display, no buttons—ideal as a pure relay/sensor node. Grove-compatible pins, I2C-expandable.

Hardware Specifications

MCU

ESP32-C3

RAM

400 KB

Flash

4 MB

Button Count

-

Has LEDs

false

Weight

4 g

Dimensions

28 x 20 x 4

LoRa Specifications

LoRa Chip

SX1262

Frequency Band

868 MHz, 915 MHz

Max. TX Power

22 dBm

Antenna Type

IPEX/U.FL

Typical Range

8 km

Connectivity

WiFi

true

Bluetooth

true

GPS

false

Power

USB Type

USB-C

Battery Connector

extern

Solar Support

false

Power Consumption (Idle)

10 mA

Power Consumption (TX)

80 mA

Firmware Support

Repeater v1.16.0 29.06.2025 Release

Release notes: https://blog.meshcore.io/2026/06/06/release-1-16-0

BLE Companion v1.16.0 29.06.2025 Release

Release notes: https://blog.meshcore.io/2026/06/06/release-1-16-0

USB Companion v1.16.0 29.06.2025 Release

Release notes: https://blog.meshcore.io/2026/06/06/release-1-16-0

Repeater v1.15.0-evo_0.1.21 14.01.2026 Release

⚠️ Check that radio.rxgain(on) and flood.advert.base (0.308) are set correctly after flashing! ⚠️

This build is based on official MeshCore 1.15.0 dev branch (as of 25-May-2026 and additionally includes the following unmerged upstream PRs/changes:

Additional changes:
  • Flood adverts are disabled (flood.advert.interval set to 0) by default
  • :new: modified PR1810 to not block flood adverts but only PAYLOADTYPEGRPTXT and PAYLOADTYPEGRPDATA so that some limited flood advert distribution can be managed via PR2553 to support e.g. observer maps.
Changelog:
  • Based on dev v1.15.0 as of 25-May-2026
Full Changelog: https://github.com/mattzzw/MeshCore-Evo/compare/v1.15.0-evo0.1.20...v1.15.0-evo0.1.21
Repeater PowerSaving15 24.04.2026 Release

Based on MeshCore v1.15 plus the below features:

Developed by IoTThinks and tested by our supportive friends and MeshCore community. Current Contribution to Meshcore: By IoTThinks%20is%3Apr%20author%3A%40IoTThinks). You may feedback there to get them merged faster to MeshCore main stream. If you want us to compile for your boards or have question, please comment in GITHUB or DISCORD

Updates:
15 May 2026: PS v15.0.2: Fixed boot loop due to flash mode for Xiao C6
10 May 2026: PS v15.0.2: Fixed FEM Off version for T096 BLE companions. The external LNA was fixed to off properly to reach -115 dbm noise floor.
04 May 2026: [BLE Companions for ESP32] PS v15.0.1: Skipped sleep when BLE read is busy and reduced sleep period from 50ms to 10ms.
27 April 2026: [Heltec v4 repeaters and room servers] PS v15.0.1: Applied latest changes in https://github.com/meshcore-dev/MeshCore/pull/2140. Fixed missing get radio.fem.rxgrain and not persisted radio.fem.rxgrain accross reboots.

Support Us

Enjoying our work? Support us via ![Sponsor](https://www.paypal.com/ncp/payment/6FGWJJVC572VL) or ![Sponsor](https://github.com/sponsors/IoTThinks).
STAR Features:
  • ESP32 BLE Companions: Officially support PowerSaving for ALL ESP32/S3/C3 BLE Companions. Fast loading of channels and contacts. Fixed hibernation mode for Heltec v3 and v4. ESP32C6 (including Xiao C6) is not supported yet.
| Board | Power Consumption | | ------------- | ------------- | | Heltec v3 | 100 mA => 19.6 mA | | Heltec v4.2 and v4.3 (FEM ON) | 120mA => 24.9mA | | Heltec v4.3 (FEM Off) | 120mA => 18mA | | Xiao S3 | 7x mA => 16.3 mA | | Xiao C3 | 7xmA => 15.1mA |
  • [BETA] Repeater and room servers: No time drift by applying a time adjustment offset during "powersaving on"
Power Saving:
Latest Power Saving to Repeater, Room Server and BLE Companion. One 3000mAh battery can last an ESP32 repeaters, room servers and BLE companions for a week.

| Role | NRF52 | ESP32 | CLI Commands |
| ------------- | ------------- | ------------- | ------------- |
| Repeater / Room Server | 8mA => 5.8mA | 50+mA => 10-13mA | powersaving on, powersaving off, powersaving |
| BLE Companion | 12mA => 5.8mA | 120mA => 15-20mA | Enabled by default |

Extra Features:
Merged to add CLI control to LoRa's FEM LNA: https://github.com/meshcore-dev/MeshCore/pull/2140. CLI: set radio.fem.rxgrain on/off and get radio.fem.rxgrain Added CLI "powerlog" to list the last reset reason, last shutdown reason (NRF52 only) and last boot voltage (NRF52 only). This is to help debugging why the boards were reset due to software fault or low voltage (brownout). Included sensor CLI to list I2C and UART GPIOs: sensor Merged to keep date after crash/watchdog/brownout reset on ESP32: https://github.com/meshcore-dev/MeshCore/pull/1896 Automatically selected I2C address 0x76 and 0x77 for BME280/BME680/BMP280 Added i2c probe for sensors to start only in-use sensors. Added variant Xiao S3 (non-Wio) and Wio SX1262 (Initial support): SDA=D6, SCL=D7 https://github.com/meshcore-dev/MeshCore/pull/2383

Instruction:

Please upgrade your easy to access devices first. Download: Download upgrade.bin to upgrade existing devices or freshInstall-merged.bin for new devices. Instruction to Flash Custom Firmware. Please read the instruction in Add sensors to repeaters Source code for PowerSaving 15

Demo

Power Saving
Enter powersaving mode (CLI > powersaving on), 5.5mA for Heltec v4.3 with FEM and rxgain off, 5.8mA if FEM off and rxgain on. 13mA for Heltec v4.2 or Heltec V4.3 with FEM and rxgain on. 5.0mA for RAK4631

<img height="384" alt="image" src="https://github.com/user-attachments/assets/be6e298d-4931-4e83-8220-0d072f8aeefd" />
<img height="384" alt="image" src="https://github.com/user-attachments/assets/924aa3a5-64d0-4112-aa66-6ff72178d3ac" />
<img height="384" alt="image" src="https://github.com/user-attachments/assets/903d899d-66c4-4d88-bf61-e9601797009f" />

Default PowerSaving for ESP32 companion BLE. Reduced from 120mA down to 15-25mA.
<img height="384" alt="image" src="https://github.com/user-attachments/assets/bcae8449-4646-4a98-852f-312582686ad6" />
<img height="384" alt="image" src="https://github.com/user-attachments/assets/2fc5bee1-fe89-4c8f-8097-2db181d89f4a" />
<img height="384" alt="image" src="https://github.com/user-attachments/assets/656fcd90-3211-4044-832b-a63f30c2fb4a" />
<img height="384" alt="image" src="https://github.com/user-attachments/assets/7611ebb5-d2d1-42b7-8845-6016e838b0cf" />

PowerLog CLI
Enter CLI "powerlog" to see last reset/shutdown reason and the battery voltage during last boot. <img height="384" alt="image" src="https://github.com/user-attachments/assets/79a31bf6-a0c2-46d3-bf7e-d63ca27e3014" /> <img height="384" alt="image" src="https://github.com/user-attachments/assets/1870c4e7-5942-466e-af0c-66e7567c7aae" />
Sensor CLI
  • Enter CLI "sensor" to check I2C and GPS Serial pins
<img height="384" alt="image" src="https://github.com/user-attachments/assets/060dd847-5984-4dc2-a5fe-cfe81180dc6c" /> <img height="384" alt="image" src="https://github.com/user-attachments/assets/49f25de7-a122-480f-a54a-a7176ec25f26" />
Repeater v1.0.1 17.05.2026 Release

Full Changelog: https://github.com/MichTronics/MeshCoreNG/compare/bridge-tcp-v1.0.5...repeater-v1.0.1

BLE Companion v1.0.1 17.05.2026 Release

Full Changelog: https://github.com/MichTronics/MeshCoreNG/compare/bridge-tcp-v1.0.5...companion-v1.0.1

USB Companion v1.0.1 17.05.2026 Release

Full Changelog: https://github.com/MichTronics/MeshCoreNG/compare/bridge-tcp-v1.0.5...companion-v1.0.1

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