Advertisement
E F G
I I I
CONVERGENCE MAP
PAGE
2 OF
5
L
There seems to be a broken connection
in the 12 volt supplies or return to
the amplifier card.
eSee Figure 6-16 to trace wiring and
isolate the failure.
NOTE: If only the -12 V supply was
lost, the fuse on the amplifier card
should have failed .
• Exchange
it if
necessary after
repairing the connection failure.
GO TO MAP 0000, ENTRY POINT BB.
14
.Switch power OFF
~.
-Exchange the fuse on
the-
amplifier card
and test.
If the fuse fails again,
exchange the amplifier card.
-See MIM Chapter 5 to make adjustments.
GO TO MAP 0000, ENTRY POINT BB.
IS
oMeter 12 V LOPT supply:
• Meter lead --- A5D02
- Meter lead --- A5B02
Is the voltage between
10
and
14
volts?
Y N
016
-Switch power OFF
~.
• Use Figure 6-16 to check the 12 V LOPT
back to the analog card.
-Isolate to one of:
a) Cables or connectors
b) Amplifier card
c) Analog card
GO TO MAP 0000, ENTRY POINT BB.
017
Set the TEST/NORMAL switch to NORMAL.
-Set the A,a/A switch to A.
.Hold down the ALT key, press the TEST
key, release both.
(This is to ensure
the screen is clear),
-Jumper C2G06 to C2D08.
Most locations on
the screen will contain an
'~'
character.
-Jumper C2W07 to C2W28.
The characters
should become white.
If the convergence
is bad they will be many-colored.
Is the convergence good (or nearly good)
near the center of the screen but gets
worse toward the edges and corners?
Y N
018
-VerifY that the convergence coil
assembly is correctly located on the
CRT.
Sea Figure 4-8.
-Attempt to improve the convergence at
the center of the screen by adjusting
the three static convergence
thumbwheels and the blue lateral
(STATIC BLAT) potentiometer.
See
Figure 1-4 and MIM section 5.3.1.
Is the convergence now nearly good at
the center of the screen, getting worse
toward the edges?
ii
H J K
H
J
K
I
019
(ENTRY POINT BB)
-Remove the jumpers.
MAP 0600-2
-Use a logic probe to probe B2G08.
(Vertical Retrace),
DO
BOTH
probe lamps light?
Y
I
;~~Change
logic card 02.
GO TO MAP 0000, ENTRY POINT BB.
021
.Switch power OFF
~.
-Exchange logic card 82, (then
th~
amplifier card, then logic card 02).
GO TO MAP 0000, ENTRY POINT BB.
022
GO TO STEP 023,
ENTRY POINT FF.
023
(ENTRY POINT
FF)
-Remove
the
jumpers.
-Use
a
logic probe to probe
B2G08
(Vertical Retrace).
Do
BOTH
probe lamps light?
Y
I
;~~Change
logi c card 02 .
GO TO MAP 0000, ENTRY POINT BB.
02S
Enter the convergence routine as follows:
-Hold down the AlT key, press the TEST
key, release both ..
.Press keys / 7 ENTER.
.Press the SPACE BAR ten (10) times.
NOTE: The next few steps check the
convergence circuits.
-Press the UP cursor key and hold for
about 10 seconds.
.Now press and hold the DOWN cursor key .
• Check that the GREEN pattern moves
diagonally down (.) 3-10 mm (0.1-0.4
inches) .
Did the
GREEN
pattern move as expected?
Y N
3
L
026
Did the
GREEN
pattern show
ANY
movement?
VI
~~7TO
PAGE 3, STEP 035,
ENTRY POINT DD.
028
GO TO PAGE 4, STEP 050,
ENTRY POINT CC.
04FEB81
MAP 0600-2
Advertisement
