The VCH-1008M 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.
Manual for VCH-1008M
– Maintenance and service manual
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– User guide
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Specifications
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 part15).
1Hz; 1/60 Hz, positive polarity pulse, width 100±0.1; 10±0.01; 1±0.01; 0.1±0.01 μs, TTL level at 50 Ω, rise time: <10 ns.
Metrological characteristics are given in the table:
| Frequency stability (Allan deviation at 25±1C°, environmental effects are excluded) | 1 s | ≤4.0·10 −13 |
|---|---|---|
| 10 s | ≤1.5·10 −13 | |
| 100 s | ≤4.0·10 −14 | |
| 1000 s | ≤1.5·10 −14 | |
| 1 hour | ≤7.0·10 −15 | |
| 1 day | ≤1.5·10 −15 | |
| Relative frequency accuracy | ±3·10 –13 (factory calibration) | ≤±1·10 –13 (in option with GPS calibrator) |
| Output signals frequency corrector |
resolution
tuning range |
1·10
−15
1·10 −10 |
| 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 | |
| 10000 Hz | ≤−155 | |
| Frequency drift (after 1 year of unperturbed, continuous operation, temperature variation no more ±1C°, environmental effects are excluded) | ≤1.0·10 −15 per day | |
| 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 (10−40 C°) | ≤5·10 −15 1/C° | |
| Magnetic sensitivity | ≤1·10 −14 1/Oersted | |
Digital control and monitoring:
all operating parameters available remotely (Windows/Linux).
Interface:
RS-232C; USB; LAN.
Power supply:
AC(100÷240)V, (50÷60)Hz; DC(22÷30)V.
Power consumption:
120 V·A (AC), 100 W (DC).
Options:
Internal GPS/GLONASS calibrator for automatic calibration.
Dimensions (W×H×D):
470 mm×200 mm×530 mm.
Weight:
27 kg.
Warranty:
3 years (10 years extended).
Life time:
15 years.
