GPS/GNSS Modules

Multi-GNSS Disciplined Oscillator Model GF-8701 Old Products (available)

TCXO equipped High sensitivity Multi-GNSS Disciplined Oscillator which achieves the world's best-in-class small size and low price.

GF-8701 outputs 1PPS synchronized with UTC as well as 10MHz coherent to 1PPS.
GF-8701 can receive concurrent GPS, GLONASS, QZSS (Quasi-Zenith Satellite System) and SBAS signals.

>> New Product:GF-8805 (Extremely high stability of 4.5ns (1sigma) using a single band receiver)



  • Generates UTC-synchronized 1PPS (pulse per second) and continuously disciplined 10 MHz

    ・Reduces errors in digital communication by providing highly accurate and stable frequency
  • Coherent behavior between time pulse (jitter less 1PPS) and frequency (10 MHz)

  • Built-in high-sensitivity timing Multi-GNSS receiver with improved noise tolerance for harsh environments

    ・Receives concurrent GPS, GLONASS, QZSS (Quasi-Zenith Satellite System) and SBAS signals
    ・Flexible antenna installation locations thanks to high sensitivity and twice the number of satellites in view as opposed to GPS-only positioning
    ・Reduces effects of internal and external noise thanks to Active Anti-Jamming and Advanced Multipath Mitigation
  • Support compatible design depending on customer's requirement

    Supports the same output format as well as pin-compatible design (GF-8701, GF-8702GF-8703)
    ・GNSSDO can be customized to meet unique customer requirements

    Timing Specifications (1PPS) Frequency Specifications
    Size (mm)
    Normal Status Holdover Normal Status (24h avg.)
    GF-8701 < ±100ns - < ±1×10-11 34 x 27 x 11
    GF-8702 < ±100ns < ±50μs/24H < ±1×10-12 34 x 27 x 15.5
    GF-8703 < ±100ns < ±10μs/24H < ±1×10-12 34 x 27 x 20
    GF-8704 < ±50ns < ±5μs/24H < ±1×10-12 100 x 52 x 20
    GF-8705 < ±50ns < ±1.5μs/24H < ±1×10-12 100 x 52 x 20

    [Test data]
    1PPS Timing Accuracy <± X μs continued from start of holdover.
     * Reference information only, values not guaranteed.
    1PPS timing accuracy
    < ±0.1μs < ±0.4μs < ±1.1μs < ±1.5μs < ±5μs < ±10μs
    GF-8702 - - 1H 2H 8H 16H
    GF-8703 - 1H 3H 4H 16H -
    GF-8704 - 2H 6H 8H - -
    GF-8705 2H 6H 18H - - -
  • Time Synchronization

    Selectable sources for time synchronization from UTC time or GPS time
  • Single satellite tracking capable operations (except Navigation Mode)

  • Antenna Connection Status Check Function

    Checks the antenna connection status (Open or Short)
    ・Assesses antenna connection failure or malfunction easily
  • Antenna Power Supply Function

    Provides power from GNSSDO directly to antenna
    ・Enabling a simplified antenna connection
  • Backup Power Supply

    Significantly reduces recovery time to GNSS lock after rebooting or interruption
  • Detect/Disable low integrity satellites (TRAIM function)

  • Synchronization with external pulse

    Enables synchronizing to time pulse from an external source
    ・Usable to synchronize to time information such as IEEE1588 or SyncE obtained through the network
    ・Improves robustness of the system
  • Arbitrary frequency output

    Enables arbitrary frequency output separately from reference frequency
  • Wide operation temperature range

    ・-40°C to +85°C
  • ITU-T G.8272/Y.1367 compliant

  • Suitable for Grandmaster clock

  • Suitable for various communication and broadcasting applications

    For infrastructure requiring product reliability
    ・Small cell applications including LTE (TDD/ MBSFN/ CoMP/ eICIC)
    ・Multimedia broadcast base stations or wireless base stations
    ・Smart grids
  • Enhance performance in combination with recommended antenna

    Multi-GNSS antenna AU-217 receives GPS signal (L1 band) and GLONASS signal (G1 band), and has highly noise resistant as well as highly environmental resistant equivalent to IP67. Multi-GNSS antenna AU-217 is suitable for use with Furuno timing Multi-GNSS modules and disciplined oscillators.
    Here's more on  Multi-GNSS antenna AU-217



GNSS Reception Capability
GNSS Reception
26 channels (GPS, GLONASS, QZSS, SBAS)
Tracking: -161 dBm
Acquisition: -147 dBm

Tracking: -157 dBm
Acquisition: -143 dBm

*Measurement platform with recommended active antenna
Initial Stabilization Time
< 5 minutes (untill lock state)
10 MHz Output
Square pulse
10MHz Output (Lock State)
Frequency Accuracy (24h avg.): <±1×10-11
Short Term Stability: <1×10-9
1PPS Output (Lock State)
1PPS Accuracy: <±100ns
1PPS Stability: 15ns (1σ)
Supply Voltage
Power Consumption
< 150 mA (3.7 V, Stable State)
Backup Supply
1.4 to 3.6VDC / 0.4 μA (Normal Operation)
Operating Temperature
-40°C to +85°C
Antenna Detection
Short and Open Detection
Outer Size
34mm x 27mm x 11mm
eSIP (NMEA 0183 Standard Ver 4.10)
Multipath Mitigation
External Referense Synchronisation, Output Status Signal

Evaluation Kit

P/N VF-01 : Evaluation kit for GF-8701

Connect the PC with a USB port to communicate. Output time pulse (1PPS) and 10 MHz reference frequency (selectable) from a SMA terminal.

Contents: GNSS antenna, CD (GNSS Conductor GF), USB cable

Evaluation kit configuration (video)
simple use by connecting the GNSS antenna with the power supply.

* Specifications subject to change without notice.