FG-09 Location and Functions of the AN-APS 504

AN/APS 504 Components

Antenna

Antenna/yoke/pedestal assembly

Waveguide Pressurization System

Waveguide to Receiver-transmitter

R-T Transmitter section

Syncronizer processor converter unit (SPCU)

Remote radar interface unit (RRIU)

Pilot Control Unit (PCU)

AN/APS 504 Antenna size and shape

42” flat-plate planar array.

AN/APS 504 rotation extent

360° rotation

Pitch, roll, and heading outputs from what are sent to antenna for stabilization.

Inertial Reference Unit (IRU)

AN/APS 504 Antenna/Yoke/Pedestal assembly stabilisation extent and antenna tilt

Stabilized up to 20° for aircraft Pitch and Roll.

Antenna Tilt from -16° to +16°

Waveguide pressurization system

Pressurized system containing nitrogen.

Maintains waveguide system at a constant pressure and humidity to prevent arcing within the waveguides at high altitudes.

Waveguide pressurization system location and components and maximum bottle pressure

Located in the radome.

High-pressure nitrogen bottle w/ gauge.

Regulator that drops bottle pressure to a maximum of 20 psi w/ output gauge.

R-T Transmitter section

modulator,

thyratron,

magnetron,

trigger amplifier,

control circuitry.

Magnetron

produces a burst of RF energy for antenna radiation.

Syncronizer Processor Converter Unit (SPCU)

Overall Radar system Timing & Control (i.e. synchronization) including;

• PRF generation

• Rx-Tx trigger pulse

• Signals to determine operation and display modes

Video/Signal processing

Radar Scan Conversion

Remote Radar Interface Unit (RRIU)

Interfaces the Radar with the NTS to allow radar operation via the NTS Radar CDU Panel.

Interfaces the Radar with the PCU allowing pilot-control of the radar when NTS is not selected.

Pilot Control Unit (PCU)

Located between the pilot and co-pilot, the PCU provides the pilot with four controls: a select switch, waveguide switch, tilt control, and range control. The three-position select switch allows selection between WX (weather) and MAP functions and transfers control of the radar to the TMT Server computer. The waveguide switch selects between transmitter and dummy load. The tilt selector controls antenna tilt between -16 and +16 degrees when the TMT Server computer is not selected. The range control provides system power-off and standby capability, and selects radar operating ranges from 25 to 200 Nm.

Operator Interface Warning

DO NOT OPERATE THE RADAR ON THE GROUND UNLESS THE WAVEGUIDE SWITCH ON THE PCU IS SELECTED TO DUM (DUMMY LOAD)

DO NOT SELECT RADAR TO TRANSMIT IF PERSONNEL ARE WITHIN 100 FEET IN THE 360° SCAN AREA, OR IF REFUELLING IS BEING CARRIED OUT ON OR NEAR THE AIRCRAFT (WITHIN 100 FEET)

Search RADAR Frequency

9375 MHz

Transmitter peak power output

100 kW

RADAR Search Ranges

3

6

12

25

50 NP

50 WP

100

200

3nm PW and PRF

0.5 microseconds

1638 pps

6nm PW and PRF

0.5 microseconds

1638 pps

12nm PW and PRF

0.5 microseconds

1638 pps

25 nm PW and PRF

0.5 microseconds

1638 pps

50nm NP PW and PRF

0.5 microseconds

910 pps

50nm WP PW and PRF

2.4 microseconds

364 pps

100nm PW and PRF

2.4 microseconds

364 pps

200nm PW and PRF

2.4 microseconds

212 pps

Scan rates at each range scale

3, 6, 12, 25, 50 NP - 30 rpm

50 WP, 100 - 12 rpm

200 - 7.5 rpm