Compact Rubidium Frequency Standard

Brandywine’s RFS-700D is a miniaturized Rubidium Frequency Reference in a compact ruggedized package designed for mounting on a DIN rail system. The RFS-700D is capable of outputting 7x 10MHz frequency reference with low phase noise.

The frequency standard includes a low phase noise oven controlled quartz oscillator, which is frequency locked to the rubidium oscillator. The time constant of this loop is selected such that the short term stability (and phase noise) of the outputs are determined by the OCXO characteristics, which the long term stability is determined from the rubidium oscillator.

The frequency standard has internal temperature sensors that are used to compensate the oscillator, based on a factory calibration, to improve the overall accuracy of the system.

This unit has been designed to meet the requirements for MIL-STD-810F for operation in demanding environments.


Input Voltage Range 18-28 VDC
Nominal Input Voltage 24 VDC
Input Connector Terminal Block
Power Consumption 15W
Connector Type SMA
No. of Outputs 7
Output Frequency 10 MHz
Output Impedance 50Ω
Short Term Stability 1 x 10-11
Aging 5 x 10-11 per Month
Phase Noise
100 Hz -138 dBc/Hz
1 kHz -151 dBc/Hz
10 kHz -165 dBc/Hz
100 kHz -165 dBc/Hz
Operating -40° C to +70° C
Storage -40° C to +85° C
Humidity 95% Non-Condensing
Operating 10,000 ft. ASL
Non-Operating 50,000 ft. ASL
Port Speed 10/100BaseT
Protocols Supported SNMPv3
Fault Reporting Output fail (1-7)
Rb Lock Status
PLL lock status
Over current (OCXO)temp