(b)
Within the receiver/transmitter, the input control data is fed to the timing, control, and monitoring circuits and the antenna stabilization circuits. The timing, control, and monitoring circuits provide timing, control, and monitoring of all functions of the receiver/transmitter.
(c)
Digital attitude reference data from the INS No. 1 and 2 is transmitted to the receiver/transmitter No. 1 and 2 respectively via ARINC 429 digital data buses.
(3)
Control Panel Functions (Fig. 3)
EFFECTIVITY
AF 121, 122; SN 351-399 CONFIG 3 01 Page 11 Apr 25/9834-43-00
(a)
The mode selector switch and gain control when in AUTO position send inputs directly to the control panel No. 1 or 2 microprocessor. Manual gain and antenna tilt inputs are processed by an analog-to-digital converter and sent to the respective microprocessor.
(b)
The digital outputs of mode, gain and tilt are sent from the microprocessors thru system 1 or 2 ARINC 429 line drivers to the No. 1 and 2 receiver/transmitters.
(c)
The system (SYS) transfer switch provides 28 volts dc switching of the waveguide switch as explained in the electrical power and power control circuits operation.
(d)
The mode selector switch positions operations are explained as follows: 1) TEST position initiates a system self-test operation and
develops a test pattern.
2) On SN 352-399, TURB position selects the turbulence mode of operation which shows areas where rainfall and winds combine to produce turbulence returns in a magenta color within 40 miles of the airplane.
3) MAP position selects the ground mapping mode. Reflected colors of green, yellow and red represent various ground returns. The TILT control must be set at a down tilt angle appropriate for ground mapping operation.
(e)
The antenna TILT control, calibrated in 1-degree increments, allows 0 to 15-degree UP or down (DN) manual tilt control of the radar antenna.
(f)
AF 121, 122; SN 351; The GAIN control is used to adjust the gain of the receiver in the MAP mode. The control may be adjusted between minimum and maximum (MAX) gain for optimum operation in the MAP mode.
(g)
On SN 352-399; The GAIN control is used to adjust the gain of the receiver in the WX, TURB and MAP modes. In the TURB mode the gain control adjusts only the weather returns. The control may be adjusted between minimum and maximum (MAX) gain or set to automatic (AUTO) for optimum operation.
(4) Antenna Functions (Fig. 3)
(a)
The Radar Antenna is an X-band, line-of-sight antenna, stabilized by a microprocessor-controlled digital servo loop located in the receiver-transmitter unit. The antenna is stabilized in roll up to |40 degrees and stabilized in pitch up to |25 degrees. The antenna can be manually tilted |15 degrees from the horizontal (zero-degree) and is stabilized over a combined tilt, pitch, and roll input of |45 degrees.
(b)
The planar array develops the required pencil beam radiation pattern by means of phase reinforcement/cancellation of energy from adjacent slots in the planar array.
EFFECTIVITY
AF 121, 122; SN 351-399 CONFIG 3 01 Page 12 Apr 25/9834-43-00
WEA RDR R/T 1 115V AC ESS RADIO BUS TEST TURB MAP GAIN CAL MODE AUTO MAX WX TEST WX TURB MAP SW P7 OVHD C.B. PNL SELECTOR 2 2 MICRO PROC CONTROL BUS LINE DRIVER AC GND B6 C11 C2 FAN C9 C7 1 POWER ENABLE J1001C (R/T) CONTROL BUS NO. 0 B7 B8 A B J1001B (R/T) DC GND DB138A (MT) 29 21 DB138B 39 P E_ PNL LTS 5V AC (33-11-00) _ H_ J DB142B G G (SHT 2) F/O IND FROM PNL CONTROL ENABLE (GND) (GND) PNL CONTROL ENABLEDB142A (SHT 2) CAPT'S IND FROM J14 K14 H14 F11 G12 62 63 64 DB109B ROLL NO. 3 46 45 PITCH NO. 5 X Y Z H L P A POWER SUPPLY P/S 429 INTER-FACE MONITOR POWER TIMING, CONTROL AND MONITORING MODULE PWR R/T ANT IND CON WG SW GYRO AIR 5 1 AMPLIFIER AGC 1.298 MHz 3RD MIXER 23.596 MHz LOGARITHMIC 23.596 MHz RCVR MON FAULT MEMORY VIDEO PROCESSOR 2 CONVERTER A/D TURBULENCE PROCESSOR & INTERFACE 3 STC ENABLE ANTENNA STABILIZATION 429 INTERFACE INTERFACE 453 21 4 BUS NO. 1 FROM CAPT'S INDICATOR (SHT 2) A B (R/T) J1001B B3 B4 CONTROL BUS NO. 2 J4 J3A B CONTROL F/O'S FROM INDICATOR (SHT 2) A A B B A B D3 D2 G2 G3 DATA BUS 1 DATA BUS 2 TO F/O (SHT 2) INDICATOR TO CAPT'S INDICATOR F H O G
GAIN CONTROL 510 A/D DC GND A B109 INS NO. 1 (E2-6) 2 TEST 236.984 MHz 2ND MIXER 2ND IF AMP MICROPROCESSOR
15 15 10 5 SYS 1 OFF 2 +5V OFF OFF 1 TILT 5V DC SYS 1 PWR SUPPLY V (SHT 2)POWER ENABLE TO R/T NO. 2 V L M K DB142B B W/G SW INTLK FREQUENCY SOURCE D7 C6 D6 +12V DC +28V DC D8 GND 78.662 MHz 49.709 MHz RECEIVER MULTIPLIER DIVIDER 9557.38 MHz 1ST MIXER 1ST IF AMP 212.38 MHz 3 MONITOR ANTENNA ANTENNA E14 E10 E11 E12 E13 C3 C8 ANTENNA PWR 115V AC MONITOR DRIVE ELEVATION ELEVATION I K J
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：747飞机维护手册AMM CHAPTER 34 - NAVIGATION 第34章导航3(95)
