Instruments, Rubidium Frequency Standard/Oscillators

FS725 - 10 MHz Rb frequency standard

Stanford Research Systems

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.FS725 Rubidium Frequency Standard 10 MHz and 5 MHz outputs 20 year aging less than 0.005 ppm Ultra low phase noise ( Built-in distribution amplifiers 1 pps input and output RS-232 computer interfaceFeatures Specifications FS725 Rubidium Frequency Standard 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 ( FS725 Single Sideband Phase Noise 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 1pps input. The relays are SPDT, providing both normally-open and normally-closed contacts. Phone: (408)744-9040 ? Fax: (408)744-9049 ? email: info@thinkSRS.com ? www.thinkSRS.com FS725 Rubidium Frequency StandardFS725 Rubidium Frequency Standard OutputOutput Output frequencies 10 MHz sine, 5 MHz sine, 10 �s wide 1 pps pulse Amplitude 0.5 Vrms, �10 % 1 pps pulse amplitude 2.5 V into 50 �, 5 V into high-impedance loads Phase noise (SSB) Spurious Harmonics Accuracy at shipment �5 ? 10-11 Aging (after 30 days)Aging (after 30 days) Monthly Yearly 20 years (typ.) 5 ? 10-9 Short term stability (Allan variance) Holdover 72 hour Stratum 1 level (1 ? 10-11) Frequency retrace �5 ? 10-11 (72 hrs. off, then 72 hrs. on) Settability Trim range �2 ? 10-9 (0 to 5 VDC) �0.5 ppm (via RS-232) Warm-up time Front-Panel Indicators (Green LEDs)Front-Panel Indicators (Green LEDs) Power "On" when AC power is applied Locked "On" when frequency is locked to rubidium 1 pps input Blinks with each 1 pps reference input applied to rear panel 1 pps sync "On" when 1 pps output is synchronized within �1 �s of 1pps input Receive Blinks when RS-232 characters are received by FS725 Send Blinks when RS-232 characters are sent by FS725 Rear-Panel ConnectionsRear-Panel Connections Frequency adjust 0 to 5 VDC adjusts frequency by �0.002 ppm (normally unconnected) 1 pps input One 100 k� input. Requires CMOS level pulses (0 to 5 VDC). If an external 1 pps input is applied, lock is maintained between the 1 pps input and 1 pps output with computer adjustable time constant from 8 minutes to 18 hours. 10 MHz outputs Two 50 � isolated sine outputs 5 MHz output One 50 � sine output 1 pps output One 50 � pulse output Optional outputs Each option board provides four 10 MHz, one 5 MHz and one 1 pps outputs. Up to 3 boards can be installed. Alarm relays Max. current, 3 A. SPDT, normally open or normally closed. May be wired in parallel with other relays to "wire-or" a single alarm. Rb lock Relay status matches the front-panel "Locked" LED. 1 pps Relay status matches the front-panel "1 pps sync" LED RS-232 9-pin connector configured as DCE, 9600 baud. Windows RbMon software is provided. EnvironmentalEnvironmental Operating temperature +10 �C to +40 �C Temperature stability ?f/f Storage temperature -55 �C to +85 �C Magnetic field ?f/f Relative humidity 95 % (non-condensing) GeneralGeneral AC power 90 to 132 VAC or 175 to 264 VAC, 47 to 63 Hz, 50 W Dimensions 8.5" ? 3.5" ? 13" (WHL) Weight 9 lbs. Warranty One year parts and labor on defects in materials and workmanship Phone: (408)744-9040 ? Fax: (408)744-9049 ? email: info@thinkSRS.com ? www.thinkSRS.com Phone: (408)744-9040 ? Fax: (408)744-9049 ? email: info@thinkSRS.com ? www.thinkSRS.com