The CH1-95 AHM is designed to operate as a source of high-stability, high-accuracy and spectrally pure frequency and timing signals.
The CH1-95 AHM has an autonomous automatic cavity tuning system, which dispenses with the use of another analogous Maser.
The CH1-95 AHM has a built-in self-test system; the unit control and parameters monitoring (including warnings on errors / malfunctions) are performed through touchscreen graphic interface (on-the-spot) and through LAN interface (remotely).
The CH1-95 AHM Applications:
Metrology, time keeping & precision time scaling, frequency reference source, global positioning / navigation satellite systems (GPS / GNSS), deep space tracking, radio astronomy with very long baseline interferometry / array (VLBI / VLBA).
Please note that some compulsory performance parameters values specified for serial production (Frequency Instability and Phase Noise especially) can be improved (tuned up / adjusted) upon a Customer's request.
PERFORMANCE PARAMETERS
Frequency accuracy and stability: |
Compulsory values |
Typical values |
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Accuracy (at shipment date) |
≤(±)1×10–13 |
≤(±)5×10–14 |
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Instability sу(2,t) at time interval t |
Compulsory values |
Typical values |
Typical values |
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1 s |
≤1,5×10–13 |
≤1,2×10–13 |
≤0,6×10–13 |
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10 s |
≤2,5×10–14 |
≤2,0×10–14 |
≤1,5×10–14 |
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100 s |
≤5,5×10–15 |
≤4,5×10–15 |
≤4,5×10–15 |
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1 000 s* |
(n/d) |
≤1,5×10–15 |
≤1,5×10–15 |
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10 000 s* |
(n/d) |
≤1,0×10–15 |
≤1,0×10–15 |
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100 000 s* |
(n/d) |
≤3,5×10–16 |
≤3,5×10–16 |
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1 h* |
≤1,5×10–15 |
≤1,3×10–15 |
≤1,3×10–15 |
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1 day* |
≤5,0×10–16 |
≤5,0×10–16 |
≤5,0×10–16 |
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* Specified / measured only under laboratory conditions: during the whole measuring period (not less than 1 day for 1 hour instability measuring; not less than 10 days for 1 day instability measuring) the ambient temperature variation shall be not more than ± 1 °C and with the rate of ambient temperature change ≤0.5°C per hour within 10 to 35 °C operating temperature range at 30 to 80 % operating humidity range; during the whole measuring period the Maser shall be protected against strong magnetic fields and vibration; during the whole measuring period the Maser supply voltage shall be constant, with the surges not more than ± 5 % of the nominal supply voltage value. |
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Frequency aging (Drift) |
≤1×10–15 (at shipment date) |
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* Typically achieved values after a year of continuous unperturbed operation: ≤ 2.0×10–16 |
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Temperature sensitivity |
≤1,0×10–15/°C (Typical : ≤0,5× 10–15/°C) |
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Magnetic field sensitivity |
≤5,0×10–15/Gauss |
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Power source sensitivity |
~ 0 (zero within the measurement accuracy) |
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Frequency settability: |
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Frequency trim range |
1×10–10 |
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Setting resolution |
1×10–16 |
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Frequency output signals (sinusoidal) |
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Output connectors type |
TNC |
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Amplitude |
1 ± 0.2 V RMS (13 ± 2 dBm) into 50 Ohms load |
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Harmonic distortion |
≤–30 dBc (for 5 MHz output) |
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Non-harmonic distortion (1 Hz - 10 kHz) |
≤–100 dBc |
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SSB phase noise (at 5 MHz, dBc/Hz): |
Compulsory values |
Typical values |
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1 Hz |
≤–116 |
≤–120 |
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10 Hz |
≤–130 |
≤–140 |
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100 Hz |
≤–140 |
≤–155 |
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1 kHz |
≤–150 |
≤–160 |
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10 kHz |
≤–150 |
≤–160 |
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100 kHz |
≤–150 |
≤–160 |
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SSB phase noise (at 10 MHz*, dBc/Hz): |
Compulsory values |
Typical values |
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1 Hz |
≤–110 |
≤–114 |
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10 Hz |
≤–124 |
≤–134 |
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100 Hz |
≤–134 |
≤–149 |
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1 kHz |
≤–144 |
≤–154 |
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10 kHz |
≤–144 |
≤–154 |
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100 kHz |
≤–144 |
≤–154 |
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SSB phase noise (at 100 MHz*, dBc/Hz): |
Compulsory values |
Typical values |
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1 Hz |
≤–90 |
≤–94 |
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10 Hz |
≤–104 |
≤–114 |
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100 Hz |
≤–114 |
≤–129 |
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1 kHz |
≤–124 |
≤–134 |
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10 kHz |
≤–124 |
≤–134 |
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100 kHz |
≤–124 |
≤–134 |
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Timing output signals (pulse) |
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Output connectors type |
TNC |
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Polarity |
Positive |
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Amplitude (output level is TTL compatible) |
2.5 to 5 V Peak (into 50 Ohms load) |
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Width |
10 to 20 μs |
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Rise time |
≤5 ns (typical values: ≤2 ns) |
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Jitter |
≤0.1 ns RMS (typical values: ≤0.02 ns) |
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Timescale correction range |
0 to 1 s |
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Timescale correction resolution |
1 ns |
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Timing synchronization pulse (synchronization to reference pulse): |
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Input connector type |
TNC |
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Polarity |
Positive |
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Input impedance |
50 Ohms |
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Time reference |
Rising edge |
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Accuracy (Synchronization error) |
≤50 ns (typical values: ≤20 ns) |
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Amplitude (input level is TTL compatible) |
2.5 to 5 V Peak (into 50 Ohms load) |
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AHM control and monitoring |
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Touchscreen graphic interface | ||||||
AHM remote control and monitoring interface |
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LAN interface control / monitoring functions: • Unit parameters (check points) control / monitoring; • Frequency control / correction within 1×10–10 s range and with 1×10–16 s setting resolution; • Timescale control / correction within 0 to 1s range and with 1 ns correction resolution; • Check points data transmission, possible errors / malfunctions data transmission. |
GENERAL PARAMETERS
Power requirements: |
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Input voltage: |
100 / 120 / 220 V ± 10 % |
DC (external)* |
22 to 30 V |
Power consumption: |
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AC |
≤ 150 VA |
DC |
≤ 100 W |
Environmental requirements: |
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Temperature: |
|
Operating |
+10 to +35 °C |
Storage |
–50 to +50 °C |
Relative humidity: |
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Operating |
up to 80 % at 25 °C |
Storage |
up to 98 % at 25 °C |
Atmospheric pressure: |
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Operating |
84 to 106 kPa (630 to 795 mm Hg) |
Storage |
12 to 106 kPa (90 to 795 mm Hg) |
Maser dimensions* (height×width×depth) |
955×550×600 mm |
* The Maser dimensions are given with an accuracy of ± 3 mm for each (height/width/depth) direction. |
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Maser weight |
100 (± 0.5) kg |
Package** dimensions* (height×width×depth) |
1280×780×870 mm |
Package** (Maser + Packing Unit) weight |
175 (± 5) kg |
** The Maser is supplied completed with an Original Packing Unit (plywood box + inner steel transportation frame with two rubber pneumatic shock absorbers). The Original Packing Unit protects the Maser against shocks and strains and provides safety of the Maser during transportation. The Maser shall be transported in its Original Packing Unit only; the Maser transportation without its Original Packing Unit can cause irreparable damage to the Maser. Please keep the Original Packing Unit for the CH1-95 Active Hydrogen Maser within the whole Maser’s lifetime. |
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Service life |
15 years |
Standard warranty period |
24 months |
Extended warranty period (upon a customer's request and at additional charge) |
up to 7 years |