BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
737-300/400/500MAINTENANCE MANUAL
H. The weather radar system R/T and control panel operate from ELEX PWR BUS-2 115-volt ac 400-Hz, single-phase from circuit breaker panel P6. No dc power is required.
I. The weather radar system has the following monitoring or self-test features: alphanumeric failure message displayed on the EHSI, and the self-test video pattern on the EHSI in the weather radar TEST mode. The operator-actuated test causes the injection of test signals, which are used to generate a test pattern on the navigation displays allowing the operator to adjust the display prior to flight and to ascertain correct operation of all system components.
J. The inertial reference system provides digital attitude data to weather radar antenna stabilization circuits.
2. Weather Radar Control Panel___________________________
A. The weather radar control panel is located on the P9 forward electronic panel.
B. The weather radar control panel provides all control data to the receiver/transmitter except range selection. It receives 28v dc power from the receiver/transmitter. The weather radar control panel provides the following controls:
(1)
The six control switches include four mode switches; WX, WX/T, MAP and TEST and an IDENT and STAB switch. The function of each switch in the on (in) position is as follows:
(a)
WX (Weather Mode) - initiates weather radar processing and display.
(b)
WX+T (Weather+Turbulence Mode) - initiates weather and turbulence processing and display.
(c)
MAP (Ground Mapping Mode) - initiates ground mapping processing and display.
(d)
IDENT (Ground Clutter Suppression Mode) - initiates ground clutter suppression processing and reduces the intensity of the displayed ground clutter.
(e)
STAB (Stabilization) - sends pitch and roll stabilization data from the inertial reference unit to the receiver/transmitter to control the weather radar antenna for changes in airplane attitude.
(f)
TEST (Test Mode) - initiates test mode and display.
(2)
GAIN control - Varies system gain in the WX, WX+T and MAP modes of operation.
(3)
TILT - The TILT settings are converted into serial data and sent to the receiver/transmitter by an ARINC 429 transmitter. Tilt settings of 15 degrees up or down from the zero position are available.
3. EFIS Control Panel__________________
A. The EFIS control panel provides weather radar display turn-on and range selection for the EHSIs. Both the captain's and F/O's EFIS control panels provide independent weather radar control for the respective display.
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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
737-300/400/500MAINTENANCE MANUAL
B. The WXR power switch provides a power enable signal (ground discrete) to the weather radar receiver/transmitter thru the weather radar control panel mode switch for system turn on. The switch also sends a discrete to the corresponding EFIS symbol generator for raster display turn-on.
C. The range selector rotary knob has six range settings which include 10, 20, 40, 80, 160, and 320 nmi. The selected range is sent to the receiver/transmitter, the EFIS symbol generator, and the flight management computer (FMC), via a common ARINC 429 data bus. The receiver/transmitter is capable of processing weather radar data for two separate selected ranges.
D. The mode selector switch will display weather radar data in the following positions: EXP VOR/ILS, MAP, CTR MAP and NAV.
4. Receiver/Transmitter____________________
A. The R/T unit is installed in a rack which has quick-disconnect waveguide fittings. The R/T is mounted in a shock mount in the pressurized area just aft of the nose radome at body station 195. Access to the R/T is gained through the lower access door forward of the nose wheel well.
B. The receiver-transmitter (R/T) contains the receiver, modulator, TR limiter, duplexer, stabilization, DC power supply, and control circuits. Peak power output from the crystal oscillator is approximately 125 watts at a frequency of 9345 MHz in the X-band. Pulse length is set between 2 to 20 microseconds depending on the range selected. Pulse repetition frequency is 180 or 1440 pps synchronized to the R/T power supply chopper frequency.
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本文链接地址：737-300 400 500 AMM 飞机维护手册 导航 NAVIGATION 3(60)
