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P-18 “Spoon Rest D”

Description of the radar set, tactical-technical characteristics
P-18 in Greding 
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Figure 1: P-18 in Greding

frequency: 150 … 170 MHz
pulse repetition time (PRT): 2.77 ms
pulse repetition frequency (PRF): 360 Hz
pulsewidth (τ): 6 µs
receiving time: 2.4 ms
dead time: 377 µs
peak power: 160 … 260 kW
average power: 540 W
instrumented range: 360 km
range resolution: 900 m
hits per scan: > 15
antenna rotation: 0 … 6 … 10 rpm


The P-18 “Spoon Rest D” (Russian designator: 1RL131 “Terek”; Cyrillic: 1РЛ131 «Терек») is a general-purpose early warning radar operating in the VHF band.

The radar is a further development of the P-12 radar and uses its concept of antenna, transmitter, and receiver. The antenna received four additional Yagi antennas for a narrower antenna pattern. The duplexer was changed because the power splitting between the two antenna planes is made directly in the antenna. The receive path received a low noise preamplifier, initially a traveling wave tube, and later a solid-state amplifier. In the receiver path, some blocks were carried over from the P-12 but got additional built-in electronic switches based on field-effect transistors for remote control. The radar signal processing after Moving Target Indication (MTI), synchronous pulse generation, and the coupling system were transistorized.

Later versions that didn't use in the former GDR received a digital MTI system, which was also offered internationally as a retrofit kit. The blocks of trigger pulse generation, potential storage tubes, and the compensation block are replaced by the new system.

The display of the radar data in the basic version happens on two PPI scopes, one of which can be replaced up to 500 m away with all remote control options. For test purposes, there is also an A- Scope.

The control of the antenna rotation is a servo-following system with multiple control inputs. It can thus work synchronously with other radar stations, which can then display the video of the P-18 in addition to or instead of their echo signal. Likewise, the evaluation of the foreign echoes can take place in the P-18 or from its remote display unit.

The inventory of a P-18 always includes a secondary radar unit. Depending on the scope of delivery, this is either a simple coded NRS-12 or a more complex “Parol” system. While the NRS-12 can still be loaded into the P-18, the “Parol” system requires an additional truck with a trailer.

The P-18 can be moved very quickly. It is mounted on two all-terrain trucks (Ural), each with a two-axle trailer. The radar is mainly used in the Eastern European area and the Third World for ManPADs (Strela, Igla). It is also used for larger missile emplacements (e.g.: coupled with a height finder) as a target assignment radar for the AA-missile complex SA-2 “Guideline”.

Picture gallery of P-18 “Spoon Rest D”
digitales SBZ

Figure 2: retrofit kit in use

Figure 3: Opened Coaxial Resonant Stub of the transmitter

Figure 4: PPI scopes

Figure 5: modernized P-18 with compensation antennas on the lower mast for improved interference protection