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Some countries which deploy early versions of the V-75 SA-2 GUIDELINE use the older ground-mounted P-8 Dolphin Knife Rest-A truck-mounted P-10 Knife Rest-B/C radars instead of the Spoon Rest. These A-band radars have an operating range of about 150-200 km.


Following the early warning station P-8 in accordance with the decree of the Council of Ministers of the USSR in 1951-1953, to protect against radio noise in the station, a transition to a different operating frequency was provided. Identification of the detected aircraft was made by the station using the attached radar interrogator NRZ-1.

In comparison with the RUS-2, RUS-2s and P-3 radars, the P-8 station was a significant scientific and technical step in the development of meter stations. It provided for the detection of aircraft in the circular viewing mode and in conditions of passive and active (radio) non-noise interference and had the following main tactical and technical parameters:

  • detection range of aircraft in the circular viewing mode at a flight height of up to 8000 m - 150 km,
  • range resolution - no worse than 2.5 km, azimuth - 24 °,
  • pulse power - from 70 to 75 kW,
  • receiver sensitivity - not worse than 7 µV,
  • total mass of the station is about 17 tons.

The station had an antenna of the "wave channel" type with a beam width in the horizontal plane of not more than 24 °. Moreover, the antenna worked both for radiation and for reception. The station included anti-jamming units and a ground-based radar interrogator NRZ-1. The station used two indicators - a circular view and altitude. The altitude indicator in combination with a goniometer made it possible to determine the elevation angle and, using the nomograms, the flight altitude of the targets.

The P-8 radar had the simplest system for moving target selection (SDC) with a coherent local oscillator without a system of inter-period subtraction. The indication of the moving target was made by the beats between the voltage of the signal and the coherent local oscillator. To synchronize the phase of the coherent voltage with the oscillations emitted by the station, an auxiliary coherent local oscillator (in the passive interference protection unit) was used.

The generator of the station worked on GI-1 lamps according to a push-pull circuit with frequency stabilization. The receiver was assembled according to a superheterodyne circuit with a dual frequency converter. The circular viewing indicator had a cathode ray tube with two fluorescent layers, glowing with blue and amber light. The first glow - blue ceased almost immediately after stopping the bombardment of the screen by electrons. The second, amber, lasted for a long time, sufficient to observe the targets during rotation of the antenna with a frequency of 2 rpm.

In the period 1949-1950 the P-8 radar successfully passed field tests (test engineer G. T. Opryshko), showing full compliance with the specified requirements. The adopted radar has been widely used in the Air Defense Forces, Air Force and Navy. For the development of the station, a team of engineers was awarded the USSR State Prize.

In 1951, at the initiative of the author and engineer of the GAU A. I. Oblezin, a new antenna mast device of 30 m in height called “Unzha” was developed for P-8 station. The purpose of this device was to press the multilobe radar radiation pattern to the ground in order to increase the detection range of aircraft. Control tests of the station with a new antenna mast device confirmed the ideas of engineers and showed that the detection of aircraft at medium altitudes (10–16 km) became possible at distances of up to 200–250 km, and at small - 60–70% further than with work on a regular antenna.

Equipping the P-8 station with two antenna-mast systems allowed the station’s calculations to easily switch its work to a standard or high-altitude mast and thereby significantly expand the tactical and technical capabilities of the radar. The high-altitude mast "Unzha" was widely used both in the air defense forces and in the control room of the civil air fleet aerodrome service radar.


The new P-10 radar was created in the Research Institute of the radio industry in the period 1951-1953, which absorbed all the best that was achieved in the station P-8 and also possessed a number of new tactical and technical qualities. The main ones were increased range and altitude of detectable targets (180–200 km and 16 km, respectively), the ability to protect against active noise interference by switching to a different operating frequency, improved protection against passive interference, and a significantly increased mobility, due to the fact that The antenna of the station was located on the same chassis with a hardware cabin and was quickly transferred from the traveling to the combat position.

Knife Rest A and GAGE, a Soviet designed EW and surveillance radar mounted on a bunkered building, made their appearance in 1952. The oldest radar in the Soviet inventory with the strict purpose of early warning, Knife Rest A had limited accuracy and detection capabilities, but was inexpensive and easily maintained. Knife Rest A has been found to operate in the 70–80 MHz frequency range. Gage proved to be the first really permanent radar of any significance that was employed by the Soviets as a search finder.

In a continuous curtain of passive interference, aircraft could be detected at an interference / signal amplitude ratio of 1.5 and with winds of less than 35 m / s. The detection range in these conditions was reduced by no more than 18% of the range when working with disabled noise protection equipment. When exposed to pulsed interference, the station detected targets even if the duration and amplitude of interference exceeded 1.5 times the corresponding signal parameters from the targets. The station also detected airplanes in continuous-wave interference with sinusoidal amplitude modulation.

The transmitter generator worked according to the push-pull scheme, its oscillating system was made in the form of a volumetric contour — a cylindrical resonator that allowed frequency tuning in the station’s operating frequency range. The antenna of the station worked without adjustment in the frequency range of the station and consisted of four identical antennas of the “wave channel” type, located on two floors, with two antennas in each. The width of the radiation pattern in the horizontal plane is from 20 to 24 °. Oblique range, azimuth and altitude of the target were determined using indicators of the circular view and height (goniometer).

In 1953, the P-10 station successfully passed ground tests and was soon adopted by the troops of the 1st Military District. It was used mainly in the air defense forces of the country, in the air force and in the navy.

It had a range of 120 km and could detect any window thrown out by aircraft, but it was very difficult for the operator to differentiate between moving and non-moving objects. This radar was the object of much complaint on the part of the radar operators. Operators considered the Pereskop radar a much betterBet than the knife-rest radar. In 1956-1957 P-8 and P-10 stations were equipped with more advanced equipment for protection against passive interference “Baikal-18” developed in SKB-197 of the State Committee for Radio Electronics (GKRE). The chief designer of the equipment was Yu. N. Sokolov. The equipment used a coherent compensation method with alternating pulse subtraction using potentialoscopes; compensation was provided for the speed of movement of the noise cloud (wind) up to 30 m / s. The equipment "Baikal-18" ensured the wiring of targets in passive interference exceeding the signals from the targets by 5 times.





Russian Designation

P-8 Dolfin



Early Warning





75-150 km

70-200 km

Detection height, km

10 km

15 km


75kw power
PW 4-12us

Associated weapon system


P-8 Radar P-8 Radar P-8 Radar

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Page last modified: 19-08-2019 16:29:43 ZULU