AN/SPN-4
Description of the radar set, tactical-technical characteristics

Figure 1: AN/SPN-4
Specifications | |
---|---|
frequency: | 3 010 … 3 100 MHz
(S-Band) |
pulse repetition time (PRT): | |
pulse repetition frequency (PRF): | 1 000 Hz |
pulsewidth (τ): | 0.4 µs |
receiving time: | |
dead time: | |
peak power: | 15 kW |
average power: | 6 W |
instrumented range: | 50 NM (≙ 90 km) |
range resolution: | 90 m |
accuracy: | |
beamwidth: | 3.5° |
hits per scan: | |
antenna rotation: | 7 rpm |
MTBCF: | |
MTTR: |
AN/SPN-4
AN/SPN-4 is operating in the S-Band navigational radar designed for non-combatant ships.
The antenna is a cut paraboloidal reflector 7 feet wide and 1 foot high, fed with a horn radiator. It uses horizontal polarization. The vertical beam width is 13.5 degrees. The antenna mounts on a rotating pedestal which houses the drive mechanism. RF energy may be fed to or from the antenna by means of a coaxial cable or a waveguide. When the distance from the transmitter/receiver to the antenna is less than 20 feet, a 50-ohm coaxial cable may be used.
Source:
- Military Standardisation Handbook TM 11-487C-1/MIL-HDBK-162A, Band 1, p. 1166