SRS FS725 Rubidium Frequency Standard with 10 MHz and 5 MHz Outputs Ultra Low Phase Noise and RS-232 Interface

The FS725 integrates a rubidium oscillator (SRS model PRS10), a low noise universal AC power supply, and distribution amplifiers in a compact half-width 2U chassis. It provides stable and reliable performance, with an estimated 20 year aging of less than 5 × 10⁻⁹ and a demonstrated rubidium oscillator MTBF of over 200,000 hours. The FS725 is an ideal instrument for calibration and R&D laboratories, or any application requiring a precision frequency standard.

There are two 10 MHz and one 5 MHz outputs with exceptionally low phase noise of (-130 dBc/Hz at 10 Hz offset) and one second Allan Variance of (<2 × 10⁻¹¹). The FS725 can be phase-locked to an external 1 pps reference (like GPS) providing Stratum 1 performance. A 1 pps output is also provided that has less than 1 ns of jitter, and may be set with 1 ns resolution.

Up to three internal distribution modules can be added to the FS725. Each module has four 10 MHz outputs, one 5 MHz output, and one 1 pps output, all with the same low phase noise, harmonic distortion and jitter.

An RS-232 interface allows direct communication with the rubidium oscillator. Using the provided Windows software, you can easily monitor and control 1 pps timing, and determine the instrument's operational status.

There are two alarm relays that indicate the status of the rubidium oscillator lock state and synchronization to an external 1 pps input. The relays are SPDT, providing both normally-open and normally-closed contacts.

• 20 year aging less than 0.005 ppm
• 10 MHz and 5 MHz outputs
• 1 pps input and output
• Built-in distribution amplifiers
• Ultra low phase noise (<-130 dBc/Hz at 10 Hz)

• FS725 Benchtop Rb frequency standard
• Option 01 Distribution amplifier (6 outputs)
• Option 02 Distribution amplifier (12 outputs)
• Option 03 Distribution amplifier (18 outputs)
• O725RMD Double rack mount kit
• O725RMS Single rack mount kit