DEC VT220 Technical Manual page 179

TO
DYNAMIC
FOCUS
(C3131
VERTICAL
OUTPUT
FROM
VIDEO
- - - - - I
VERTICAL
LOGIC PROCESSOR
VERTICAL
1--""'-....,........
WINDINGS
OF
r--........
..J
YOKE
' - -_ _.--J
ASSY
Figure 8-14 vertical Deflection Circuit
Block Diagram
FROM
-12V +12V
FILTER
D301 "
IN4004
C308
1
"r-
150V
V-LIN
R308 nR307
47K lOOK
R3()6
562K
R305
221K
1
R310
196 33 1/2'11 ,
C305
1---'-------4'1
if---,
JOOPFT
C310
4 SOOV 10100V
}
TO/FROM
10 VERTICAL
F h - - - - - - - - - - + + _
OUTPUT
11 5
E301
TDA 11705
C303
;:;::100
25V
R30i
4.7K
c...2.
J2 R254
PIN
15
f-~lwK
......,_ _8,
r
I
~~'-;""1'-6..,.--....,,7R-3~1~4~2:--+----r,
- - - - l
)'!f------l
~
390K
I
I
~3~~v
1
~EIGHTl
I
C304 R303 C306 R309
T 1 -- 250K "r'2200P 820K
150V l00V
I I
i
GND
c
l---L.........
- - - - I . - - I . - . l . . - - - ' - - - - - ' - - - - - - - . . . L . . -....... GN00
MA<013!>8A
FROM VER IN
VIDEO
LOGiC
Figure 8-15 Vertical Processor Circuit Diagram
The vertical processor circuit
following components/circuits.
(Figure 8-15) consists of the
• Vertical processor device (E301)
• Vertical sync input (R254 and R301)
• Voltage regUlator (D301 and R301)
• Oscillator synChronizer (R302 and C304)
• Current regulation (R303 and R304)
• Ramp sensor (R306)
• Power amp stabilization network (R305, R3l0, C305, C306,
and C310)
• Vertical linearity control (R308, R307, C307, and C308)
8-13