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NRS-12 „Score Board”
Figure 1: Antenna of the interrogator NRS-12
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”)
| Specifications | |
|---|---|
| frequency: | UHF-Band |
| pulse repetition time (PRT): | synchron to the PSR |
| pulse repetition frequency (PRF): | 200 ... 750 Hz synchron to the PSR |
| pulsewidth (PW): | 12 Microseconds |
| receive time: | |
| dead time: | |
| peak power: | 4 Kilowatts |
| average power: | |
| displayed range: | |
| range resolution: | 450 m |
| beamwidth: | 20 Degrees |
| hits per scan: | > 10 |
| antenna rotation: | synchron to the PSR |
Figure 2: Principle of operation of the Kremnij 2 system
Figure 3: opened codefilter Nr. 4
Figure 4: filter set of the
P-15 radar
Figure 5: Rack NRS-12 in a
P-18 radar
