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G H
2 2
I
025
VIDEO HAP
PAGE
3 OF
.Switch power OFF
~.
-Check the continuity of the connections
below.
See Figure 1-4 for plug
locations.
VIDEO
LOGIC
Through VIDEO CARD
SIGNAL
Wire ITP.
Green
C2S11
A5Dll
P14-5
I
Gl
Red
C2Ull
A5D12
P14-7
RI
Blue
C2S12
A5D13
P14-9
B1
-Repair any problem found or exchange
logic card E2 then the video card.
GO TO MAP 0000, ENTRY POINT BB.
26
.Switch power OFF
~.
-Remove the P14 connector from the video
card.
See Figure 1-4 .
• Switch power ON
m.
.Set the TEST/NORMAL switch to NORMAL.
.Use a LOGIC PROBE to look at the 3 video
signals on the logic board.
GREEN
=
A5Dll
RED
=
A5D12
BLUE
=
A5D13
Are
any
of them DOWN
all
the time?
Y N
027
-Verify the +5V supply to the video
card.
(See Figure 6-7.) If no problem
found, Switch power OFF
~
and exchange
the video card.
GO TO MAP 0000. ENTRY POINT BB.
028
.Switch power OFF
~.
-Measure the resistance to ground of the
suspect signal.
Is it 10 ohms or less?
j
y
;~~Change
logic card C2.
GO TO MAP 0000. ENTRY POINT BB.
30
There appears to be a short to ground.
-Disconnect logic card C2.
Has the short disappeared?
Y N
031
-Look for a failure in the wlrlng
between the video card and the logic
board or on the logic board.
See
Figure 6-7 and Figure 3-1.
GO TO MAP 0000, ENTRY POINT BB.
32
-Exchange logic card C2.
GO TO MAP 0000. ENTRY POINT BB.
F
2
133
.Switch power OFF
~
.
HAP 0300-3
• Reseat the video card on the CRT.
-Switch power ON
m.
.See Figure 6-9 to check that the
following supplies are present on the
card.
TEST
VOLTAGE
POINT
TOLERANCE
70
+70 Vdc
+10 V
- 5 V
8.5
+8.5Vdc
±0.9V
5
+5
Vdc
±0.5V
RG
-20V to -80Vdc
NOTE: RG comas from the
-150V supply and is changed
by the BRIGHTNESS control.
Are the voltages correct?
Y N
03'1
-See Figure
1-4
and Figure
6-7
to check
bad voltages and cable connections .
• Exchange the failing FRU.
GO TO MAP 0000. ENTRY POINT BB.
035
.Switch power OFF
~.
-See Figure
6-7
to verify the continuity
of the VIDEO FORCE signal.
-See Figure
6-7
to verify the continuity
of the connections to the Intensity
Override switch on the brightness
potentiometer.
-If you find no problem, exchange the
video card.
GO TO MAP 0000. ENTRY POINT BB.
04FEB81
HAP 0300-3
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