Stanford FS700 LORAN-C Frequency Standard
serves as a NIST traceable frequency reference (Distributed only in Germany.)
Specifications in Brief
Overview
The FS700 LORAN-C Frequency Standard produces a highly stable and accurate 10 MHz output by locking its oven stabilized crystal oscillator to LORAN-C radio transmissions. The FS700 system consists of a receiver containing amplifiers, filters, data acquisition circuitry, and a remote antenna. The long term stability of the FS700 is that of the transmitted standard, an atomic cesium source. An internal phase meter circuit allows for the precise frequency calibration of external oscillators. An optional distribution amplifier provides multiple outputs of the 10 MHz reference.
| Receiver | ||
| Sensitivity | Will lock with signal-to-atmospheric noise level of -10 dB or better | |
| LORAN output | Filtered and gain controlled antenna signal, typically 6 Vpp | |
| Station search | All available stations pre-programmed, Auto-Seek finds and tracks strongest station | |
| Notch filters | 6 adjustable -30 dB notch filters, 3 at 40 to 90 kHz, 3 at 110 to 220 kHz | |
| Frequency | ||
| Frequency stability | ||
| Long term | 10-12, the same as LORAN-C transmitter cesium clock. | |
| Short term | 10-10 (standard oscillator), 10-11 (low phase noise option) | |
| Outputs | Four 10 MHz outputs, 1 Vpp sine into 50 W | |
| LOCK output | Rear panel TTL indicates receiver lock. | |
| Front panel output | TTL level output from 0.01 Hz to 10 MHz in a 1, 2.5, 5 sequence. | |
| Internal Oscillator | ||
| Standard | Option 01 | |
| Frequency | 10.000 MHz | 10.000 MHz |
| Type | AT Cut Ovenized | SC Cut Ovenized |
| Aging | 5x10-10/day | 5x10-10/day |
| Allan variance (1s) | 5x10-11 | 5x10-12 |
| Stability 0-50° C | 0.005 ppm | 0.005 ppm |
| Phase noise | -125 dBc @ 10 Hz | |
| -130 dBc @ 100 Hz | -155 dBc @ 100 Hz | |
| -165 dBc @ 1 kHz | ||
| Phase Meter | ||
| Frequency output | 0.01 Hz to 10 MHz in 1, 2.5, 5 sequence, TTL level. Can be 50 W terminated. | |
| Oscillator input | 1 kW, 0.5 Vpk min, 5.0 V max. | |
| Phase output | 0.01 V/degree, 0 to ± 360 °. Output proportional to phase difference between OSC IN and FREQUENCY OUTPUT for frequencies between 100 kHz and 10 MHz | |
| Computer Interface | ||
| GPIB | IEEE-488 compatible interface. All instrument functions may be controlled. GPIB interface is standard. | |
| RS-232 | Optional 300 to 19,200 baud DCE serial interface. All instrument functions may be controlled. | |
| Antenna | ||
| Type | 100 kHz active antenna, with 40 kHz bandwidth bandpass filter in base. | |
| Height | 102" | |
| Material | Fiberglass Whip | |
| Base | 2" dia. x 7.5", PVC | |
| Mounting | 3/4" FIPT | |
| Output | 50 W nominal, female BNC | |
| Environmental | -40 to 60 °C, 0 to 100 % RH | |
| Lightning Protection Module: | ||
| Surge | 18,000 A IEEE 8/20 waveform (based on ANSI C62.1) | |
| Frequency range | DC to 30 MHz | |
| Throughput energy | <16 mJ (based on 1 KV/nS waveform) | |
| Insertion loss | <0.25 dB | |
| General | ||
| Operating | 0 to 50 °C | |
| Power | 100/120/220/240 VAC (+5%, -10%), 50/60 Hz, 50 W | |
| Dimensions | 17 " x 17 " x 3.5 ". Rack mounting hardware included. | |
| Weight | 14 lbs | |
| Warranty | One year parts and labor on any defects in material or workmanship |
