The CHK7-56 Receiver-Comparator is designed for measuring relative frequency deviation of high-stable crystal oscillators or quantum generators in relation to time signal frequency formed in accordance with signals of GLONASS/GPS satellite navigation systems.

The Frequency Standard automatically locked to GLONASS/GPS signals provides local time scale formation synchronized to UTC (SU).


The Instrument’s principle of operation is based on measurement of phase difference incursions in the time domain of time scale signals. This time scale is formed from a built-in or an external oscillator reference frequency and a reference time scale signals. The time scale is formed on the base of GLONASS/GPS signals received and processing results with further determination of a relative error of an external oscillator frequency in the receiver-comparator mode or automatic internal reference rubidium oscillator synchronization in the frequency standard mode.


Relative error of high-stable oscillator frequency deviation measurement in the receiver-comparator mode:

1·10–12 per 1 day

1·10–13 per 10 days

Input signals: 5, 10 MHz

Relative output signal frequency error in GLONASS/GPS satellites tracking mode 2·10–12per 1 day

Output signals (2 outputs): 1; 5; 10 MHz (sinewave); 10 MHz (TTL)

Relative two-sample output signal frequency deviation (rms):

1.5·10–11 per 1 s

6.0·10–12 per 10 s

3.0·10–12 per 100 s

Main (2 outputs) and auxiliary scales

Principal time scale synchronization error to UTC (US): not more than 50 ns

Interfaces: GPIB, RS 232


Operating temperature range: 5°С to 40 °С

Relative humidity at 25 °С : not more than 95 %

Power: 220±22 V, 50±1 Hz

Power consumption at nominal AC voltage:

in a warm-up mode (30 min): 160 VA

in a settled mode: 120 VA

Dimensions: 520х158х340 mm

Weight: 12 kg