HOLYBRO Microhard Telemetry Radio V2

HOLYBRO Microhard Telemetry Radio – Professional Data Radio System for UAVs and Unmanned Systems

The HOLYBRO Microhard Telemetry Radio is a high-performance telemetry and data radio system for UAVs, UGVs, robotic platforms and other unmanned systems. It integrates a professional Microhard Pico Series RF module and enables robust wireless transmission of serial data between the vehicle, flight controller and ground station.

Depending on the Microhard variant used, the radio system supports different network topologies including Point-to-Point, Point-to-Multipoint and, with the P900 version, a self-organizing mesh network with automatic routing. This makes the system suitable for both conventional telemetry links and more complex communication architectures involving multiple network participants.

For robust wireless transmission, the system uses Frequency Hopping Spread Spectrum (FHSS). This technology enables reliable wireless transmission of asynchronous serial data and is particularly suitable for professional applications with demanding communication requirements.

Microhard Pico Series RF Technology

The HOLYBRO Microhard Telemetry Radio integrates an RF module from the Microhard Pico Series. Different frequency ranges and data rates are available depending on the selected version.

The P900 version operates in the 902 to 928 MHz frequency range and additionally supports mesh communication. The P400 version operates in the 410 to 480 MHz range. Permitted frequencies and transmission power depend on the applicable regulations of the respective country or operating location.

• P900: 902–928 MHz
• P400: 410–480 MHz
• P900 Data Rate: up to 276 kbps
• P860 / P400 Data Rate: up to 345 kbps

Point-to-Point and Point-to-Multipoint

The Microhard Telemetry Radio supports robust communication structures for different system architectures. In addition to a conventional direct connection between two radio modules, Point-to-Multipoint configurations can also be implemented.

• Point-to-Point communication
• Point-to-Multipoint communication
• Serial data transmission
• Suitable for more complex radio networks

Mesh Network with Automatic Routing

The P900 version additionally supports true mesh operation with automatic routing. Multiple compatible radio modules can communicate with each other and forward data within the network.

This functionality enables flexible communication networks to be created for applications where multiple unmanned systems, ground stations or other network participants need to be interconnected.

Note: Mesh functionality is available exclusively with the P900 version.

Frequency Hopping Spread Spectrum

The Microhard system uses Frequency Hopping Spread Spectrum (FHSS) for wireless data transmission. The radio communication switches between different frequencies within the available frequency band according to a defined hopping sequence.

This technology supports robust data transmission and reduces the impact of individual interference signals within the operating frequency range.

Direct Connection to Flight Controllers

The HOLYBRO Microhard Telemetry Radio features a 6-pin JST-GH connector. This allows the radio module to be connected directly to the TELEM port of many compatible flight controllers.

This enables compact integration of the telemetry system into UAVs, VTOL platforms, UGVs and other autonomous systems.

USB-C with Integrated USB-to-UART

The current V2 version features a USB-C connector with an integrated USB-to-UART converter. A separate UART-to-USB adapter is therefore no longer required for configuration.

A dedicated switch allows the operating mode to be changed for firmware parameter configuration. Settings can be configured either via AT commands through the data port or using Microhard PicoConfig software.

Flexible Power Supply

The radio module features an XT30 power connector and an integrated high-voltage BEC. This provides a wide input voltage range of 7 to 35 V DC and simplifies integration into different power supply architectures.

• Input Voltage: 7–35 V DC
• Power Connector: XT30
• Integrated high-voltage BEC

Status Indicators

Multiple integrated LED indicators provide quick visual monitoring of the operating status and radio connection.

• UART transmission LED
• Three-level RSSI indicator
• Diagnostic port LED

Data Integrity and Error Correction

For reliable data transmission, the Microhard system supports several mechanisms for detecting and correcting transmission errors. These include 32-bit CRC, configurable retransmissions and Forward Error Correction (FEC).

• 32-bit CRC
• Configurable retransmission
• Forward Error Correction
• Low-latency transparent data transmission

Diagnostics and Network Control

A separate diagnostic port provides additional functions for monitoring and managing the radio connection. Transparent remote diagnostics and online network control are supported.

Features

• Professional telemetry and data radio system
• Microhard Pico Series RF technology
• Frequency Hopping Spread Spectrum (FHSS)
• Point-to-Point communication
• Point-to-Multipoint communication
• Mesh communication with automatic routing on P900
• Data rate up to 276 kbps with P900
• Data rate up to 345 kbps with P860 and P400
• Low-latency transparent data transmission
• 6-pin JST-GH connector for compatible flight controllers
• USB-C connector
• Integrated USB-to-UART converter
• Configuration via AT commands or PicoConfig
• XT30 power connector
• Integrated high-voltage BEC
• 7 to 35 V DC input voltage
• UART transmission LED
• Three-level RSSI indicator
• Diagnostic port LED
• 32-bit CRC
• Configurable retransmission
• Forward Error Correction (FEC)
• Remote diagnostics and network control

Technical Specifications

For Professional Unmanned Systems

The HOLYBRO Microhard Telemetry Radio is suitable for professional UAV, VTOL, UGV and robotics applications requiring a powerful and flexible radio connection between unmanned systems and ground stations.

With support for multiple network topologies, FHSS, error correction and – with the P900 version – mesh communication, the system can also be integrated into more extensive communication architectures. Direct JST-GH connectivity, USB-C configuration and the wide input voltage range simplify integration into custom-developed unmanned systems.

Note: Frequency range, transmission power and operating mode must be selected and configured in accordance with the applicable radio regulations of the respective country and operating location.