915Mhz 3DR RadioTelemetry

Lowest
Greater range and a superior performance to the XBee radios .
Available in 915Mhz and 433Mhz
Serial plate ( by air) and USB ( to the ground)

The system provides a full-duplex link modules HM -TR HopeRF running custom firmware , open source . Standard interface module through 5V TTL / serial FTDI .

The SiK firmware includes a bootloader that allows firmware updates serial port, you can also set the parameters by radio.

Firmware upgrades and configuration are fully compatible with APM Mission Planner . The configuration is also possible through the Configurator 3DR or AT commands.
Moden 3DR Radio 2 x 915MHz one for "earth" and another for " Avion"
1 x Cable telemetry
2 x 6 pin right angle
FTDI Cable 1 x 3.3 V
2 x RP- SMA Antenna 900MHz 2dBi "
Features and Specifications:

Very small size
Lightweight ( less than 4 grams without antenna)
 version 915MHz
Receiver sensitivity -121 dBm
Load capacities up to 20dBm (100mW )
Data rates up to 250kbps
MAVLink protocol processing and status reporting
Frequency Hopping Spread Spectrum ( FHSS )
Adaptive time division multiplexing ( TDM )
Support for LBT and AFA
Configurable duty cycle
Error Correction Code (can be up to 25 % correct bit errors in data)
Range of several kilometers with a small omni antenna
It can be used with a bidirectional amplifier to have a range of more distance
Open Source Firmware
The AT commands, radio settings
The RT command to configure remote radio
Adaptive flow control when used with APM
Based on the radio module HopeRF HM- TRP with microcontroller RF SiLabs SI1000 .