Designed for comparison of time and frequency standards output signals.

Main applications: standard time and frequency complexes, automatic measurement systems.


The Instrument principle of operation is based on conversion of 5 MHz or 100 MHz compared frequency signals into 1 Hz pulse signals with relative frequency instability increase by 104 times. An external Time Interval Meter can measure frequency instability.

The Phase Comparator Unit has three options: 5 MHz, 100 MHz, 5 and 100 MHz input frequencies (4 channels).


Compared frequencies nominal values: 5, 100 MHz

Deviation from nominal value: not more than 3.5.10–7

Number of independent comparison channels: 4

Relative frequency instability multiplication factor: 104

Input signal rms value: 1±0.2 V

Compared frequency relative difference: not more than 1.10–10 (At frequency instability measurement for 1 s is not more than 1.10–8)

Phase variation temperature coefficient in operating temperature range:

at 5 MHz not more than 20 ps/ °C

at 100 MHz not more than 10 ps/ °C

rms frequency comparison accuracy not more than:

Averaging time

Frequency comparison accuracy

5 MHz

100 MHz

I s



1 h



Measurement accuracy at 1 h measurement time is guaranteed for ambient temperature variation within ±1 °C


Operating temperature range: 5–50 °C

Relative humidity: up to 98 % at 25 °C

Power: 220±22 V, 50 Hz, 22–30 V dc

In case of a power line failure the Instrument switches automatically to 22–30 V external power supply without additional measurement error

Power consumption: 70 VA, 50 W

Dimensions: 480x 200x555 mm

Weight: 27 kg