3DR Radio telemetry 433MHZ /868MHz /915MHZ module kit

The item is a professional and practical single TTL 3D Robotics 3DR radio telemetry kit, which is the ideal way to setup a telemetry connection between your APM and a ground station. Small, inexpensive and with great range, the 3DR radio uses an open source firmware which allows us to do things that cannot be done with other radios. 
Features 
- Color: as shown in the pictures. 
- Shell material: hard plastic and metal. 
- 100% brand new and high quality Single TTL 3D Robotics 3DR Radio Telemetry Kit 915MHZ Module. 
- Very small size, and Light weight (under 4 grams without antenna). 
- Available in 900MHz or 433MHz variants. 
- Receiver sensitivity to -121 dBm. 
- Transmit power up to 20dBm (100mW). 
- Transparent serial link. 
- Air data rates up to 250kbps. 
- Range of approx 1 mile. 
- 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. 
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Package Including 
1 * Single TTL 3D Robotics 3DR Radio Telemetry Kit ( 433MHZ or 868MHz or 915MHZ ) for APM2