Loran-C and eLoran Timing Receiver

Enclosure version UN-151B

The UN-152A is a small form factor timing receiver that uses the latest version of UrsaNav’s Mitigator™ series Low Frequency (LF) receivers. The UN-152A provides precise time, frequency, and data channel demodulation from Loran-C or eLoran systems. It features a serial port, a GPIO port and both 1PPS and 10MHz inputs and outputs. The receiver is capable of processing Chayka and other low or medium frequency sources.

The UN-152A meets the stringent European Telecommunications Standards Institute requirements for Primary Reference Clocks, the Stratum–I frequency requirements, and provides traceability of time to within 50 nanoseconds of UTC. Built-in future–proofing ensures capability to track next generation LF signals with advanced waveforms and enhanced data channel capability.

As solutions experts for LF Position, Navigation, Timing, Frequency, and Data technology; UrsaNav has you covered from transmission to reception. Our turnkey solutions include system design, timing and control equipment, advanced data channel techniques, and differential Loran reference equipment.

Key Features

  • Small size enclosure
  • NMEA messaging
  • Complete range of integration capabilities
  • Software configurable
  • Intuitive user-friendly graphic display software
  • Loran-C, eLoran, Chayka
  • Flexible SDR architecture


View the full product description


The UN152A is a standalone enclosed eLoran receiver that contains our UN-151B LF receiver module. This version is capable of receiving Loran-C, eLoran, and Chayka signals, including all existing versions of Loran Data Channels (i.e., 9th pulse, 10th pulse, and Eurofix).

Download the UN-152A Product Fact Sheet (PDF)

Technical Specifications

  • Timing Specifications: ETSI EN300 462-6-1 / ITU G.811
  • Maximum Time Interval Error: < 50ns from UTC; < 25ns for 100s intervals; < 100ns for intervals <1000s
  • Hold-over: < 5 μs / 24 hrs
  • Timing source: 1 to 3 radio transmitters with automatic handover
  • Time to First Fix: 30 seconds
  • Position Update Rate: 1 Hz
  • Accuracy (95%): 10-20m Stand-alone eLoran absolute positioning accuracy in differential eLoran mode
  • Stations tracked: All in view
eLoran Engine
  • Sensitivity: 30-120 dB μV/m
  • Dynamic Range: 96 dB
  • Signal Processing: Band pass/notch filtering, cross-rate cancellation, moving average TOA integration
  • Loran Data Channel: Eurofix, 9th / 10th pulse
  • Heading: <1 degree with H-field antenna
  • Dimensions: 230 x 100 x 50 mm robust aluminum enclosure
  • Weight: .7 kg
  • Input Voltage: +5VDC (+/- 5%)
  • Power Consumption: 14 W
  • Serial port (RS-232 level)
  • 115200 baud
  • NMEA Messaging
  • GPIO Port
  • 10 MHz frequency output
  • 1 PPS eLoran UTC output
  • 10 MHz frequency input
  • 1PPS input
  • Power and 1 PPS LEDs
  • Operating Temperature: -40°C to +65°C
  • Storage Temperature: -50°C to +75°C
  • Humidity: 95% noncondensing
  • Dual Core ARM/DSP Software Defined Radio
  • Firmware upgradable
  • On Board FPGA and flash memory
  • Meets RTCM SC127 draft MPS spec
  • Meets ETSI PRC requirement
  • Meets Stratum-I frequency spec
  • eLoran UTC recovery
  • Full eLoran, Loran-C, Chayka capable
  • Differential Loran capable
  • Position, Frequency, Time & Data
  • GNSS Integration ready
  • Stand-alone, ASF and Differential Positioning
  • User friendly intuitive GUI for Windows XP/7
  • Allows monitoring, archiving and control of UN-151 series
    • Time of Arrival trending
    • Position Scatter plot
    • Loran Data
    • Channel display
    • Command interface
    • Replay of recorded data
    • FFT