Description of the radar set, tactical-technical characteristics
Figure 1: Type 274
|frequency:||3 230 … 3 340 MHz
|pulse repetition time (PRT):|
|pulse repetition frequency (PRF):||500 Hz|
|pulsewidth (τ):||0.5 µs|
|peak power:||400 kW|
|instrumented range:||16 NM (≙ 30 km)|
|range resolution:||80 m|
|accuracy:||100 m; 5 minutes|
|hits per scan:|
Type 274 was British naval main battery fire control radar using a Double-Cheese antenna operating in F-Band.
The antenna type AUM consists of two cylindrical paraboloid reflectors each approximately 14 feet by 14½ inches aperture mounted on the director control tower. The antenna type AUM was stabilized in elevation. Its vertical beamwidth was 13 degrees. The unstabilized antenna AUO, which was narrower in height (14 inches), had a vertical beamwidth of 23°. The transmitter used spark gap modulation.
Type 274 development begun in September 1941. The radar began to be phased in on some major British warships from May 1944.