The Passive Hydrogen Maser is a compact hydrogen maser with excellent frequency stability and utilises state-of-the-art technology. Full digital processing of the modulation and servo loop signals makes it ideal for high accuracy applications. An internal GPS/GLONASS option is available and provides automatic output signal frequency calibration.
Key applications:
– National Time Keeping Service
– Space tracking and navigation
– Verification of frequency signals
– Scientific research
Output signals:
Sine: 5 MHz; 10 MHz; 100 MHz, (1±0.2) V RMS into 50 Ω load.
Pulse: 2,048 MHz (square pulse), 1,5÷2,8 V (pp) into 75 Ω (ITU-T G.703 part13).
1Hz; 1/60 Hz, positive polarity pulse, width 10±0.1 μs, TTL level at 50 Ω, rise time: <10 ns.
Metrological characteristics are given in the table:
| Relative frequency accuracy | ±3×10−13 (factory calibration) |
≤±1×10−13 (in option with GPS calibrator) |
|
| Output signals frequency corrector | resolution retuning range |
1×10−15 1×10−10 |
|
| Frequency stability (Allan deviation at 25±1C°, environmental effects are excluded) |
1 s | ≤5.0×10−13 | |
| 10 s | ≤2.0×10−13 | ||
| 100 s | ≤5.0×10−14 | ||
| 1 hour | ≤9.0×10−15 | ||
| 1 day | ≤4.0×10−15 | ||
| Phase noise spectral density (dBc/Hz) (5 MHz output) |
Frequency offset | Spectral density (dBc/Hz) | |
| 1 Hz | ≤−105 | ||
| 10 Hz | ≤−130 | ||
| 100 Hz | ≤−145 | ||
| 1000 Hz | ≤−155 | ||
| Manual synchronization to external 1 pps TTL signal accuracy |
≤±25 ns | ||
| Time synchronization to UTC using GPS | ≤±50 ns (using optional GPS calibrator) | ||
| Temperature sensitivity in temperature operating range (10−35 C°) |
≤±1×10−14 1/C° | ||
| Magnetic sensitivity | ≤±2×10−14 1/Oersted | ||
Digital control and monitoring: all operating parameters on local LCD display, or also available remotely.
Interface: RS-232C; USB; LAN.
Power supply: 100–240 V AC, 50–60 Hz, or 22–30 VDC.
Power consumption: 120 VA AC, 100 W DC.
Options: 1. DC power supply 38.4–57.6 V (two inputs); 2. Internal battery for autonomous operation; 3. Internal GPS calibrator for automatic calibration.
Dimensions (W×H×D): 470 mm×200 mm×530 mm.
Weight: 33 kg.
Warranty: 3 years.
Life time: 15 years.