Bad Elf Flex Base/Rover

Bad Elf Flex Base/Rover


Brand: Bad Elf



Authorized Dealer

Bad Elf Flex Base/Rover

  • (2) BE-GPS-6500 - Bad Elf Flex Extreme GNSS Receivers
  • (2) BE-URK-5000 - UHF Flex Radio Kits 
  • A full Base / Rover Solution
  • (Rover Rod Poles Sold Separately)
  • Bad Elf introduces a base/rover feature built upon the Bad Elf Flex GNSS receiver. 
  • This new base/rover feature brings affordable centimeter-level accuracy to surveyors and geospatial professionals working anywhere in the world. 
  • The solution consists of two Flex GNSS receivers and two UHF radios, allowing customers to perform high-accuracy field data collection in areas where traditional RTK corrections or cellular coverage is not available. 
  • Existing Flex customers can upgrade to a base/rover solution by adding a Flex radio kit, one for the base and one for the rover.
  • Built on the survey-grade Hemisphere Phantom GNSS engine
  • Expected accuracy - 1 cm horizontal in good conditions
  • Quad-constellation corrections source from base to rover
  • Range (power-determined) 2-10 km line-of-sight
  • Global operations, regardless of cellular coverage
  • A professional system for a cost-competitive price without sacrificing features or functions
  • No need for dedicated devices and configurations. 
  • Bad Elf Flex Extreme operates as either a base or a rover. (Rover mode is available with Flex Standard using a Flex Token to enable Extreme mode)
  • Simply fire up the Flex app and enable either mode of operation.

An intuitive tool to ensure best practices, built upon lessons learned from the aviation industry. Designed to mitigate error and improve efficiencies in the field.
  • Pole height and antenna configuration
  • Tilt check and calibration
  • GNSS lock
  • Battery checks
  • Radio connectivity checks
  • Configuration of base location via here point or known point, with associated datum metadata
  • Reliable GNSS checks
  • CSV logs
  • Standard Rinex is compatible with OPUS and many other post-processing systems
  • JSON metadata for events and project details
  • Standard NMEA streaming via Bluetooth or USB
  • FCC-approved radios with callsign support
  • The radio kit includes a checklist for customers to obtain an FCC license with recommended frequency coordinator
  • Radio LCD screen supports configuration and status monitoring
  • Radio charging is available via provided AC adapter
  • Includes protective equipment case, charger, and mounting accessories
  • Fully compatible with iOS and Android phones and tablets
  • Bluetooth connected - clean setup with no wires
  • Primary interface via Flex utility app
  • Standalone operation from the Flex LCD screen for use without a connected phone or tablet
  • Native multi-rover support
  • Constellation health
  • Tilt-check as well as a movement indicator
  • Radio connectivity issues
  • Bluetooth connection loss
  • Flex and radio battery state-of-charge
  • All events  logged with data and packed with timestamps for maximum integrity
  • Should a recorded session need to be defended for truth or accuracy, everything that is needed to recreate a session is included in one place

Bad Elf Flex UHF Radio Kit Details:
  • The Flex radio kit provides a UHF radio link used for communicating corrections from a Flex operating as a fixed base station to one or more Flex units operating as rovers. 
  • A Flex radio connects via Bluetooth to Flex and requires no additional cables. 
  • For more information see the Bad Elf Flex base/rover page or contact
  • Operating Frequency: 450mHz to 470mHz frequency range.
Radio Kit Contents:
  • Harxon Radio HX-DU1603DUHF Antenna
  • Rugged carrying case
  • AC wall charger
  • Charging/Serial Cable
  • Survey pole mount

Bad Elf Base / Rover Configuration Manual


BAD ELF FLEX Extreme Specs:
  • PART NUMBER: Model BE-GPS-6500 (formally BE-5500GPS)


  • GPS: L1CA / L1P / L1C / L2P / L2C / L5
  • GLONASS: G1/G2/P code (P1/P2)
  • BeiDou: B1/B2/B3 (separate variant without L5)
  • Galileo: E1BC / E5a / E5b
  • QZSS: L1CA / L1C / L2C / L5


  • Horizontal accuracy - RTK: 1 cm
  • Horizontal accuracy - SBAS (WAAS): 30-60 cm
  • Horizontal accuracy - Autonomous: 1.2 m
  • Horizontal accuracy - L-Band via Atlas: 4 cm
  • Timing (1PPS) accuracy: 20 ns
  • Cold start time: < 60 s typical (no almanac or RTC)
  • Warm start time: < 30 s typical (almanac and RTC)
  • Hot start time: < 10 s (almanac, RTC, and position)
  • Maximum speed: 1,850 kph (999 kts)
  • Maximum altitude: 18,288 m (60,000 ft)
  • Differential options: SBAS, Autonomous, External RTCM v2.3, RTK v3, L-band (Atlas), and DGPS
  • Correction I/O protocol: Hemisphere GNSS ROX, RTCM v2.3 (DGPS), RTCMv3 (RTK), CMR, CMR+, Atlas


  • USB: USB 2.0 device via Mini-USB receptacle, USB 2.0 host OTG via supplied adapter
  • Bluetooth: Bluetooth V4.0 (HS) with integrated Class 1.5 PA, Supports 3 simultaneous connections
  • Wi-Fi: 802.11b/g/n


  • Platforms: iOS, Android, Windows
  • Mobile App: The Bad Elf Flex App requires iOS 9.0+ or Android 9+
  • Connectivity: Bluetooth SPP, USB Serial


  • Operating: 4F to +131F (20C to +55C)
  • Battery Powered: -14F to -140F (-10C to +60C)
  • Externally Powered: -22F to +140F (-30C to +60C)
  • Charging Temp: 41F to +113F (+5C to +45C)
  • Storage Temp: 40F to +167F (40C to +75C)


  • Full RTK: 11 hours
  • L-band Atlas: 8 hours


  • User interface: Transflective, LCD, Membrane Buttons, 3 multicolor LEDs, Audible tones
  • Dimensions: 10.0 x 2.75 / 254mm x 70mm
  • Weight: 29oz / 854g
  • Helical Antenna Phase Center: 23cm above base of Flex unit without adapter installed, Add 1.5cm with adapter installed


  • Humidity: 100% condensing
  • Waterproof: IP65


  • USB Port: Mini-USB port for charging and ElfPort expansion
  • Accelerometer: 3-axis
  • Display: 400 x 240 pixel transflective LCD screen with backlight
  • Firmware: Field upgradeable via app or USB

1Constellations and frequencies are dependent on receiver configuration and subscriptions.

Bad Elf Flex UHF Radio Kit Specs:
Frequency Range
  • 410-470MHz
  • Channel Spacing
  • 25 kHz / 12.5 kHz
  • Operating Mode
  • Half-duplex
  • Modulation Type
  • Channels
  • 36(programmable)
  • Operation Voltage
  • 9~36V
  • Power Consumption(typical)
  • High power 7.5 W@12 V DC
  • Low Power 4.0 W@12 V DC
  • Standby 1.2 W@12 V DC
  • Frequency Stability
  • ≤1.0 ppm
Structural Specification
  • Size 15.81" (47.6 mm) X 3.26" (83 mm) X 1.25" (31.5 mm)
  • Weight
  • Approx. .14.46 OZ  (410 g)
Antenna Interface
  • TNC Female
  • Antenna Interface Impedance
  • 50 ohm
  • Data Interface
  • LEMO 5pin
  • Air Baud Rate
  • 9600bps / 19200bps
  • Serial Port Baud
  • 9600 bps / 19200 bps
  • 38400 bps / 115200 bps
  • RF Output Power: 410~470 MHz
  • High Power(2.0W)33.51.0 dBm @ DC 12 V
  • Low Power (0.5W) 27.51.0 dBm @ DC 1 2V
  • Power Stability: 1 dB
  • Adjacent Channel Power: >50 dB @ 25 KHz
  • ReceiverSensitivity: -115 dBm @ BER 10-5,9600 bps
  • Co-channel Rejection: >-12dB

User Manual 

User Manual

WARNING - This product contains chemicals known to the state of California to cause cancer, birth defects or other reproductive harm.  For more information go to