10 MHz Ultra Low "Close-In" Phase Noise with Stabilized PPS

The NR6720-HS-A6 features extremely low frequency jitter despite being GNSS locked. GNSS locking brings a long-term stability to an OCXO that is difficult to match. Instead of an accuracy of 50 ppb/year - accuracies of ~E-12 are readily achieved. However, locking an OCXO to the GNSS presents its own set of problems. The timing information from the GNSS is burdened with all the noise one would expect from a RF link - multi-path, reflections, etc. Long-term stability is enhanced frequently at the expense of “close-in” stability. Low frequency components from the RF link are introduced to the OCXO, often degrading the Allan Deviation of the OCXO. The NR6720-HS-A6 uses a unique crystal and proprietary control loop to minimizing “close-in” degradation while securing long-term stability. The unit also features very low PPS pulse to pulse jitter. Instead of the +- 10 ns of PPS jitter from the receiver, the PPS stabilizer reduces PPS jitter to under 800 ps.The unit also offers a high resolution time stamp that can capture up to 25 events at a rate of 10 kHz.

  • Holdover stability of 5 ppb/day,  50ppb/year

  • P-P Frequency jitter~ 2E-12 (see frequency deviation plot)

  • PPS stability option- P-P jitter < 600 ps

  • Locked accuracy <4E-11

  • Available -60 to +60 VDC in three ranges

  • Concurrent reception of GPS and GLONASS

  • PPS accuracy 20 ns rms

  • Time stamp to 1 us

  • Secondary channel synthesized frequency

  • Indicators and signals provide GPS/GNSS lock and unit self-test status

  • Optional Composite PPS in 5 MHz reference signal

  • NMEA Available vis RS232 port

Typical Phase Noise

Odoo CMS - a big picture