(3)
A normal test pattern is shown in Fig. 6. A TEST message will be present in slot 1.
(4)
If the test fails a flashing FAIL message will be present in the top center of the indicator (slot 2). A failure effecting the color scheme will be identified by a modified color scheme. The following messages in the color bar will identify the failed unit.
(a)
Receiver/Transmitter Fault - R/T
(b)
Antenna Fault - ANT
(c)
Control Panel - CTL
(d)
Indicator - DSP
E. System Shutdown Procedures
(1) On weather radar control panel, set controls and switches to following position.
(a) Mode select - TEST
EFFECTIVITY
AF 160, 162-171, 183, 184 CONFIG 4 01 Page 38 Sep 25/9434-43-00
(b)
AF160, 162-171;
System transfer switch - 1
(c)
AF183, 184;
System transfer switch - OFF
(d)
TILT control - 0 degree
(e)
GAIN control - CAL
(f)
AF 160, 162-171;
GND CLTR SPRS - OFF
(g)
AF 183, 184;
GND SPRS - OFF
(2)
On both weather radar indicators, set controls and switches to following position.
(a)
MKR intensity control - fully counterclockwise
(b)
INT control - fully counterclockwise
(c)
Range switch - 80
(d)
M/S switch - master mode position
(e)
AF 160, 162-171;
AZ switch - off (azimuth marks displayed)
(f)
AF 160, 162-171;
HOLD switch - off (mode disabled)
(g)
FWD switch - pressed
(h)
AF 160, 162-171;
PWR switch - off
(3)
Place all four weather radar circuit breakers on P7 panel to open position.
(4)
Shut down INS 1 and 2 (Ref 34-41-00).
(5)
Remove external electrical power if no longer required (Ref 24-22-00, Maintenance Practices - Apply Power).
EFFECTIVITY
AF 160, 162-171, 183, 184 CONFIG 4 01 Page 39 Sep 25/9434-43-00
WEATHER RADAR SYSTEM - TROUBLE SHOOTING
_______________________________________
1. General
_______
A. The following trouble shooting procedures are based on performance of the system operational test and are presented in tree-type format. The test steps (heavy-line boxes) are connected by shaded arrows to show the OK condition path. When all steps in the OK condition path check out, the system is operable.
B. When a test step does not check out, follow the NOT OK line to the box containing the trouble symptom. Turn to the procedure indicated and continue to follow a single line by analyzing the results of each test step until the required corrective action is determined. Perform the specified corrective action; then repeat the step at which the failure was encountered.
C. The self-test features incorporated in the system provide a quick means of evaluating system performance. When the TEST mode is selected at the control panel function selector, a special test pattern is generated for evaluation of a large portion of the system. In addition the system incorporates fault isolation circuitry which provides visual indication, on the receiver-transmitter units front panel, of an existent malfunction within the system. By utilization of the internally generated test pattern together with the outputs of the system fault indicators and annunciators, the system is capable of detecting most system malfunctions.
NOTE: In some instances, to gain access to the R/T front panels for
____ observation of fault indicators/annunciators, a walkway/dripshield panel located over the R/T units must be removed.
D. The self-test features incorporated in the system provide a quick means of evaluating system performance. When the TEST mode is selected at the control panel function selector, a special test pattern is generated for evaluation of a large portion of the system. In addition the system incorporates fault isolation circuitry which provides visual indication, on the receiver-transmitter units front panel, of an existent malfunction within the system. By utilization of the internally generated test pattern together with the outputs of the system fault indicators and annunciators, the system is capable of detecting most system malfunctions.
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