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,
G H
2 2
122
ANALOG IIA!'
PAGE
3 OF
5
-Turn HEIGHT control fully
counterclockwise.
See Figure 1-4.
Is lamp 2 lighted?
Y N
023
-Switch power OFF
~.
-Exchange the analog card.
-If this corrects the problem,
GO TO MAP 0000. ENTRY POINT BB.
-If the problem remains,
GO TO STEP 037.
ENTRY POINT EE.
024
-See MIM section 5.3.5 to make necessary
adjustments to raster.
-Switch power OFF
~
and exchange the
analog card
if
raster can not be
correctly adjusted.
GO TO MAP 0000. ENTRY POINT BB.
25
-See Figure 1-2 and the table below to
check the output voltages at the analog
card socket P4.
-Use the brightness potentiometer mounting
plate as meter ground.
ANALOG CARD
VOLTAGES
SOCKET (P4)
AND
PIN NO.
TOLERANCES
31
+12 Vdc ±1.5V
50
erp)
+6.3Vdc ±0.8V
43
-150 Vdc
48
erp)
+70 Vdc
Are they all correct?
Y N
02(,
±20 V
HO V
-5 V
Is pin 43 between -70 and -170 volts?
Y
I
i~7TO
STEP 037.
ENTRY POINT EE.
028
Is pin 50 voltage wrong?
Y N
029
-Switch power OFF
~.
-Exchange the analog card.
GO TO MAP 0000. ENTRY POINT BB.
J
K
J
K
MAP 0400-3
to
NOTE: The filament voltage (P4-50) can
rise to 12 Y de or more
if
there is a
broken connection to the filament or
if
the filament has an open circuit.
-Measure the voltage beh ... egn analog card
P4-31 (12 Vdc) and P4-47 (return).
IS there more than 8 Vdc?
Y N
031
-Switch power OFF
~.
-Exch~nge
the analog card.
GO TO MAP 0000. ENTRY POINT BB.
032
There may be an open circuit in the 6.3
V supply or return to the CRT filament.
-Switch power OFF
~~
-Use Figure
6-7
to check continuity.
-See Figure
4-7
for filament resistance.
-Isolate to one of:
a)
Wiring or connectors
b)
CRT fi lament
c) Video
card
d)
Analog card
GO TO MAP 0000. ENTRY POINT BB.
033
-Engage Intensity Override.
(Turn th@
brightness knob fully counterclockwise.)
Is there any
im~ge
on the screen?
Y N
034
-Release Intensity Override.
Is the CRT filament lighted?
Y N
035
-Switch power OFF
~.
-See Figure
6-7
to measure voltages
and resistances to isolate the
failure.
-ExchBnge the failing FRU.
GO TO MAP 0000. ENTRY POINT BB.
03(,
-Turn HEIGHT control fully
counterclockwise.
IS problem solved?
Y N
037
lEt/TRY POINT EEl
-Swi tch pm.,jer OFF
121
and remove the
power cord from the mainline power
socket.
-Remove the analog card.
-~isconnect
the deflection coils
(Connector P6, near the center of the
analog card with 4 colored wires) -
see Figure
4-7.
-Inspect P6 for loose and dirty
contacts and broken wires.
-Repair any damage.
Did you find the problem?
iI
4 4 4 4
L M N P
04FEB81
MAP 0400-3
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