Details about 3DR Radio Telemetry Kit 915Mhz Module For APM Aerial Photography

The Radio telemetry system base on 3DR Radio system and 100% compatible.
It's designed as an open source Xbee replacement radio set, offering a lower price, longer range (approx one mile) and superior performance to Xbee radios. It’s available in 915Mhz and 433Mhz; and in the following configurationsserial board (for the air) and USB (for the ground).
The system provides a full-duplex link using HopeRF's HM-TRP modules running custom, open source firmware. Interface to the module is via standard 5V-tolerant TTL serial / FTDI USB serial.
Firmware upgrades and configuration are fully supported in the APM Mission Planner. Configuration is also possible through the 3DR Radio configurator and AT commands.

Features
Small size and light weight
Available in 915MHz or 433MHz variants
Receiver sensitivity to -121 dBm
Transmit power up to 20dBm (100mW)
Transparent serial link
Air data rates up to 250kbps
MAVLink protocol framing and status reporting
Frequency hopping spread spectrum (FHSS)
Adaptive time division multiplexing (TDM)
Support for LBT and AFA
Configurable duty cycle
Built in error correcting code (can correct up to 25% data bit errors)
Demonstrated range of several kilometers with a small omni antenna
Can be used with a bi-directional amplifier for even more range
Open source firmware
AT commands for radio configuration
RT commands for remote radio configuration
Adaptive flow control when used with APM
Based on the HopeRF HM-TRP radio module, featuring an SiLabs Si1000 RF microcontroller.

Datasheets of HM-TRP module: http://www.hoperf.com/upload/rf_app/HM-TRP.pdf
Documentation: http://code.google.com/p/ardupilot-mega/wiki/3DRadio
Radio Configurator(Air module need a USB-UART tool like FTDI to configure): http://vps.oborne.me/3drradioconfig.zip
Board schmatic:

Dimension: Air / Ground module (no include SMA connector)17m x 35mm / 17mm x 59mm
Weight: Air / Ground module: 4.6g/16.8g (include cable and antenna) / 7.2g/17g (include antenna)

Air Module(915Mhz) x 1
Ground Module(433Mhz or 915Mhz) x 1
UART 4Pin cable for Air module 300mm x1
2.5dbi Antenna for two module x2