GPS Disciplined Oscillator Module

The GPS Disciplined Oscillator Module is a small Commercial –Off-the-Shelf (COTS) GPSDO that has been designed to meet military requirements such as MIL-STD-188-164A. At only 4.1” x 2.75” x 1” (104.0 x 70.0 x 26.0 mm) in size, the unit provides Stratum 1 performance.


Model NumberDescriptionOscillator TypePower SupplyPower TypeOutput FormatInput Format
GPSDOGPS Disciplined OscillatorOCXO12 VDCDC1PPS, 10 MHzGPS
CMCCompact Master ClockOCXO12 VDCDC1PPS, 10 MHzGPS
XMCXMC Distribution AmplifierNone12 VDCDC1PPS, 10 MHzGPS
CMC-ITRCompact Master Clock - Industrial Temperature RangeOCXO12 VDCDC1PPS, 10 MHzGPS
XMC-ITRXMC Distribution Amplifier - Industrial Temperature RangeNone12 VDCDC1PPS, 10 MHzGPS


  • 3 isolated low phase noise 10MHz outputs
  • Internal GPS Tracking Receiver
  • External 1 PPS input
  • Small footprint designed for easy integration
  • Disciplined high stability OCXO

The GPSDO supplies three isolated, low noise precision 10 MHz frequency reference signal outputs.  These outputs are accurate to 1×10-12 when slaved to a timing supply from an internal GPS tracking receiver.

The frequency standard is also able to slave to an external 1PPS signal to steer and hold the internal oscillator and clock system precisely in time. Time and frequency information maintains its high accuracy with the internal oscillator even when no satellites can be tracked.  A serial data port is provided to report time, date, position, and GPS satellite health and signal strength.  The GPSDO module also has dual power supply inputs and can operate off either supply input. Optional capabilities include automatic interface to an external military GPS receiver such as the Defense Advanced GPS Receiver (DAGR), Ethernet Interface for NTP time service and SNMP status monitoring. Standard frequency output is 10 MHZ, but other frequencies are possible.


GPS Input
Connector Type MCX
Signal Type C/A Code
Number of Channels 12
Receiver Sensitivity -155dBm
1PPS Level 0-5V
Have Quick (opt) per ICD-GPS-060
Power 12 VDC +/- 5%
Power Consumption 15W Warm up, 5W nominal
Number of Inputs 2 diodes in an OR configuration
Time Accuracy GPS < 30 ns
1PPS < 30 ns
Holdover <20us in 24 hrs
Warm Up / Stabilization Time
Cold Start 20 Minutes
Dimensions 104mm x 70mm x 26mm
1PPS Output
Number of Outputs 1
Connector Type MCX
10 MHz Output
Number of Outputs 3
Output Level J2:        min. 15dBm, max 17dBm
J3, J4:   min. 11dBm, max 12dBm
Connector Type MCX
I/O Connector
I/O Connections Power A (12/15VDC)
Power B (12/15VDC)
Alarm Out
1PPS Input
Force Holdover/HQ input (option)
Operating -20 to +70 degrees C
Storage -40 to +85 degrees C
Humidity Up to 95% RH (non-condensing)
Altitude 50,000 ft Non-operating
10,000 ft operating
EMC Emmission FCC Part 15, EN55022, EN55024

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