Canon LV-7545U, Руководство по обслуживанию

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2) No picture at computer input
Check that the RGB signals are observed at pins 19-20, 23-24 and 27-28 of K10Q on
the AV unit and K8B on the main board.
Check that the synchronizing signals (CG_HSYNC, CG_VSYNC) are observed at pins
11-12 and 13-14 of K10Q on the AV unit and K8B on the main board.
Check that the RGB signals are observed at test points TP20R, TP21R, TP20G, TP21G,
TP20B, and TP21B.
Check that the synchronizing signal is observed at test points TPHS and TPVS.
Check that the CG1/CG2 switching signal is observed at pin 22 of IC5201 and pins 16
and 11 of IC5204. The CG1/CG2 signal is output from pin 50 of IC801.
CG1: Low CG2: High
Check that the CG/HD switching signal is observed at pin 22 of IC201 and pins 9 and
10 of IC3231. The CG/HD signal is output from pin 52 of IC1801.
CG: Low HD: High
3) No picture at both video and computer input
Check that the RGB signals are observed at test points TP20R, TP21R, TP20G, TP21G,
TP20B and TP21B.
Check that the synchronizing signals are observed at test points TPHS and TPVS.
Check that the clamp pulse signals are observed at test points IC211 and IC212.
4) No picture at DVI (digital) input
Check the 5V voltage (5VDVI) at pins 1 and 2 of K10P.
Check that the synchronizing signals are observed at pins 47 and 48 of IC8001.
Check IC8001 and peripheral circuits.
5) No picture at all inputs
Check that the RGB S&H signal is observed at test points TP501, TP1501, TP531,
TP1531, TP561 and TP1561.
Check that the NRS signal is observed at test point TP2551.
Check 15.5V, 15VP power supply line and peripheral circuits.
Check IC501, IC1531, IC561, IC1501, IC1531, IC1561, IC9401, IC401 and IC3301
and peripheral circuits.
Part 4: Troubleshooting
4-5
Signal/terminal K10Q/K8B Signal/terminal K10R/K8A
CG1/CG2-SW 5-6 AV_Y/Video 3-4
H-Sync 11-12 AV_PB 7-8
V-Sync 13-14 AV_PR 11-12
B 19-20 S_SW-IN 15-16
G 23-24 IN2/IN3-SW 33-34
R 27-28 S-Y 47-48
S-C 51-52