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Description of the radar set, tactical-technical characteristics Описание; Основные тактико-технические характеристики (Базы данных)
Antenna of the interrogator NRS-12

Figure 1: Antenna of the interrogator NRS-12

Specifications
frequency: UHF-Band
pulse repetition time (PRT): synchron to the PSR
pulse repetition frequency (PRF): 200 ... 750 Hz
synchronously to the PSR
pulsewidth (τ): 12 Microseconds
receive time:  
dead time:  
peak power: 4 Kilowatts
average power:  
instrumented range:  
range resolution: 450 m
beamwidth: 20 Degrees
hits per scan: > 10
antenna rotation: synchron to the PSR

NRS-12 “Score Board”

Score Board is very early equipment since it has an antenna array consisting of two horizontal rows of two radiators per element. The two double rows are mounted one above the other to give a four-array of what appears to be a total of 32 dipole radiators. The whole system is mounted on a rectangular rotatable framework.

The “Kremnij-2” interrogator transmits a group of pulses. The Transponder modulates these pulses with an audio frequency. There are 12 different frequency filters.

The number “12” in the designator means, that this interrogator was designed for the radar set P-12 and the following models of the “Spoon Rest” VHF-radar family. The working on the same principle (“Kremnij-2”) interrogator variant NRS-20 was designed for the P-37 “Bar Lock” (its predator was the so called “P-20” radar). An other version fitted in an own trailer was a part of the SA-2 “Guideline” (alias S-75 “Wolchow”)

uplink format
friendly aim
downlink format
(uplink pulses modulated
with an audio frequency)

Figure 2: Principle of operation of the Kremnij 2 system

uplink format
friendly aim
downlink format
(uplink pulses modulated
with an audio frequency)

Figure 2: Principle of operation of the Kremnij 2 system

Picture gallery of NRZ-12
offener Filter 4
Figure 3: opened codefilter Nr. 4
Filter set of the P-15 (“Flat Face”)
	(click to enlarge: 1024·768px = 40 kByte)
Figure 4: filter set of the P-15 radar
Rack in P-18
Figure 5: Rack NRS-12 in a P-18 radar