The receiver comparator CH7-38 (CH738, CH7 38, CH-738, CH 738, CH 7 38)
The receiver comparator CH7-38 is designed to determine the frequency deviation of quartz or atomic frequency measures in relation to the frequency of signal model (reference) frequencies from a radio station very long and long waves.
- Research, development and manufacture of quartz and lasers;
- Verification of quartz and atomic frequency measures in metrological laboratories;
- Study of the propagation of radio waves;
- Synchronization measures of frequency and time in universal time systems and navigation systems.
Technical characteristics of the instrument receiver comparators CH7-38:
- Ambient temperature - from -10 º C to +50 ° C (from 263K to 323K);
- Relative humidity - up to 98% at +25 ° C (298K);
- Voltage - 220 V ± 22 V, 50 Hz and 115 ± 6 V and 220 V ± 11 V ± 10 Hz frequency of 400 Hz;
- DC supply voltage + (27V ± 3V);
- Atmospheric pressure - from 61.3 kPa to 104kPa (up to 780mm of 460mm.rt.st Hg).
Frequency range of signals received comparator device receiver CH7-38:
- 5 kHz-79, 9 kHz and 66 (6) kHz - no converter with step adjustment 0.1 kHz;
- 178kGts-287, 8 kHz - the converter with a step adjustment 0.2 kHz.
Sensitivity of the instrument receiver comparator CH7-38 is not worse
- 0.1 mV - in the frequency range 5 kHz-79, 9 kHz and 66 (6) kHz;
- 10mkV - in the frequency range 178kGts-287, 8 kHz.
The bandwidth of the receiver - 15Hz-30Hz.
The selectivity of the receiver unit, a comparator CH7-38 is not worse
- 80 dB - for the image channel in the frequency range 5 kHz-79, 9 kHz and 66 (6) kHz;
- 16dB - on the image channel in the range 178kGts-287, 8 kHz;
- 40 dB - Adjacent channel (at offset of ± 100 Hz of the frequency of the received signal).
The weakening of the attenuator unit receiver comparator CH7-38 - from 0dB to 80dB in steps of 10 dB.
Accuracy attenuation attenuator - ± 4dB.
When the voltage of the input signal within the AI-20mkV 60mkV device provides an indication of congestion broadband channel receiver.
When the voltage signal at the input device AI within 0.3 mV, 3mkV device provides an indication of congestion tract intermediate frequency receiver.
Input impedance instrument receiver comparator CH7-38 Input AI - 25 Ohm, 100 Ohm.
Protection device (limiting) of the input channel receiver of signals from high-limit input signal at a level not to exceed 0.6 V.
The unit produces the following output signals:
- 2 kHz frequency pulses, 1 MHz; 128kGts-207, 9 kHz to 0.1 kHz; 130kGts, 100Hz in a big way not less than 2V, the load of 1 kOhm;
- HRA the connector - DC toga, which varies from - (4V ± 1V) to + (4V ± 1V) for a load of 10 ohms.
The device is a receiver-comparator CH7-38 has the following modes: "Lock," "The sound signal," "Indemnification," "More," "Less," "Stop," "Measurement", "Reset" button.
Limit of acceptable relative error comparisons of the frequency of the local and the received signal r collects the results of phase measurements does not exceed ± 5 ∙ 10 -12 at the time of measurement, and 24 ± 5 ∙ 10 -13 at a measurement time of 10 days.
The device is a receiver-comparator CH7-38 is powered by a sinusoidal signal of a local frequency standard parameters:
- Frequency - 0.1 MHz, 1MHz, 5MHz, 10MHz;
- The relative frequency deviation from the nominal value - no more than 5 ∙ 10 -7;
- Signal level from 0.5V to 3V into 50 ohms.
The instrument provides information about the phase advance in a parallel 24-bit BCD.
When passing power unit receiver comparator CH7-38 from the AC to DC power supply and back the instrument generates digital data without a glitch.
When powered from an external source of DC + (27V ± 3V) may be affected by the point of reception channel at frequencies of 20 kHz ± 2 kHz, 40kHz ± 4 kHz, ± 60kGts 6kGts, 75.9 kHz ± 4 kHz.
The interface unit comparator receiver CH7-38 provides:
- The interface functions in accordance with Table 1;
- Provision of information in the public channel (CPC) on the results of measuring the phase shift of the signal in seconds.
Table 1: Interface functions of the device receiver comparator CH7-38
The device provides specifications after the time of establishing the mode of 15 minutes.
Normal operating conditions the instrument receiver comparator CH7-38:
- Temperature - 20 º C ± 5 º C (293 K ± 5 K);
- Relative humidity at 25 º C - 65% ± 15%;
- Atmospheric pressure - 100kPa ± 4kPa (750mm.rt.st. ± 30mm.rt.st.);
- Mains power:
- Voltage - 220 V ± 4,4 V;
- Frequency - 50Hz ± 0,5 Hz.
Limiting conditions of operation of devices receiver comparators CH7-38:
- Temperature - from -60 º C to +65 º C (213K to 338K);
- Relative humidity at 25 º C - 98%;
- Atmospheric pressure - 12kPa (90mm.rt.st.).
The device is a receiver-comparator CH7-38 retains its specifications within the rules, the working conditions, as well as after exposure to extreme conditions, followed by exposure to normal or operating conditions for 2 hours.
The device allows for continuous operation under the operating conditions for 24 hours while maintaining performance.
MTBF unit receiver comparator CH7-38 - at least 4,500 hours.
Service life - 10 years.
Lifespan of the device receiver comparator CH7-38 - 10,000 hours.
Dimensions in millimeters and weight in kilograms device are shown in Table 2.
Table 2 Dimensions in millimeters and weight of the instrument receiver comparator CH7-38 in kilograms