(b)
Loss of the time base will blank GMT and disable all the indications.
(c)
The control switches provide electrical grounds for logic circuits in the microprocessor. The clock and CHR switches are latch (F/F) circuits to prevent interference from the switch contacts. Grounding the test pin (10) causes the seven segment display to show all 8's.
B. BITE
(1) All clock failures are indicated in the same manner. The clock displays go blank and the sweep second hand is frozen. In addition, transmission of GMT output data words is halted.
C. Control
(1)
Provide electrical power (AMM 24-22-00).
(2)
Check that the following main power distribution panel P6 circuit breakers are closed:
(a)
ON GUN 006-999;
6G2, CLOCK TIME BASE L
(b)
ON GUN 006-999;
6G3, CLOCK TIME BASE R
(c)
ON GUN 001-005;
6G3, CLOCK TIME BASE L
(d)
ON GUN 001-005;
6G4, CLOCK TIME BASE R
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MAINTENANCE MANUAL
(3)
Check that the following overhead panel P11 circuit breakers are closed:
(a)
ON GUN 001-005;
11J9, CLOCK IND LEFT
(b)
ON GUN 006-999;
11B17, CLOCK IND LEFT
(c)
11J35, CLOCK IND RIGHT
(4)
Operate the GMT switch to control and display Greenwich Mean Time.
(5)
Operate the ET switch to control and display Elapsed Time or operate the CHR switch or the remote CLOCK switch to display the Chronographic Time, as applicable.
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CLOCKS
COMPONENT SHT 102 FIG. QTY ACCESS/AREA REFERENCE
CIRCUIT BREAKERS -- FLT COMPT, P6
CLOCK TIME BASE L, C563 1 6G2; 6G321 *
CLOCK TIME BASE R, C576 1 6G3; 6G41 2 *
CIRCUIT BREAKERS -- FLT COMPT, P11
CLOCK IND LEFT, C573 1 11B17; 11J91 2 *
CLOCK IND RIGHT, C574 1 11J35 *
CLOCK - CAPT, N2 -- 1 FLT COMPT, P1 31-25-01
COMPUTER - (REF 34-61-00, FIG. 101) FLT MGT R, M135 FLT MGT L, M134 CLOCK - F/O, N42 -- 1 FLT COMPT, P3 31-25-01
SWITCH - CAPT CLOCK, S320 -- 1 FLT COMPT, P7 *
UNIT - (REF 31-31-00, FIG. 101) DGTL FLT DATA ACQUISITION, M138 SWITCH - F/O CLOCK, S321 -- 1 FLT COMPT, P7 *
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本文链接地址：757 AMM 飞机维护手册 仪表 CHAPTER 31 - INSTRUMENTS 1(30)
