IBM 3279 2A Maintenance Information page 98

~~~
~'-
""
Ground Braid
Clamp
Video Card - Rear View
Figure 6-9. Video Card Test Points
---
Amplifier
\0
Card
0:
:0
I
~)6)
- -6)
6)
~
6) 6)
6)
R
G B
6)
6)
6)
P17A P17B
I I
1e1
8
Jumper
link
Test Points
,
~'
BO
co
P19
DO
EO 14
FO
GO
"0
~
J 0
K 0p18
LO
MO
NO 16
Figure 6-10. Amplifier Card Test Points
3279 MIM
Test
Point
5
8.5
70
-'--
6
RI
GI
BI
400
GT
RG
GG
BG
Notes:
Description
+5 V de
+8.5 V de
+
70 V de (video amps)
Return 0 V
+6.3 V de (Heater)
Red Video Amp,
Green Inputs
Blue 10.5 V)
Anode Voltage (+-280 to +450 V del
Intensity Override (0.5 V)
Red Grid
Green Voltages
Blue 10 to -150 VI
1. Rllall Cards except IBM Part 5148396)
2. RI Icard IBM Part 5148396)
CAUTION: Probing the wrong RI point may
short-circuit land patterns and damage cards.
A
Blue Lateral
1
Convergence
B
Blue Coil
C
Green Drive
0 Red
E
Red
1
F
Green Analog Inputs
G Blue from 82 card
H Blue Lateral
J
Blue Bright-up
K +12 V de IFused)
-150 V de
M
+12 V de
N -12 V de
Chapter 6. Support Information 6-27