Toshiba MM20E45, Техническое учебное пособие

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8-5
2-4 V Linearity Characteristic Correction
(1) S-character Correction
(Up-and Down-ward Extension Correction)
A parabola component developed across C306 is integrated
by R306 and C305, and the voltage is applied to pin 6 of
IC302 to perform S-character correction.
(2) Up- and Down-ward Linearity Balance
A voltage developed at pin 2 of IC301 is divided with
resistors R307 and R303, and the voltage is applied to pin 6
of IC302 to improve the linearity balance characteristic.
Moreover, the S-character correction, up- and down-ward
balance correction, and M-character correction are also
performed through the bus control.
3. VER CENTERING CIRCUIT
This circuit is designed so that user can adjust picture to desired position on screen, in spite of various signals which exist as
input signals in RGB mode.
Fig. 9
Supplying current to Q309 from deflection yoke L462 causes
picture position to move up, in reverse supplying current to
L462 from Q308 causes position to move down. This control
can be done by remote control unit or key on TV set. Micom
IC sends data to DAC IC ICX001 via T-Bus line, and the
output is sent from pin 12 to pin 5 of Ope. amp ICK09 to
adjust base voltages of Q308 and Q309. To memorize picture position, control data;1 for TV and 4
for RGB are stored in Memory IC ICA02.
Micom reads out the data which responds the selected mode,
and sends it to DAC. As a result, picture position automatically
fits to the preadjusted position.
I C-Bus
2
ICA01
MICOM
ICA02
MEMORY
ICX001
DAC
12
6
5
7
ICK09
Q307
Q309
Q308
R325
C325
R305
C306
L462
+30V
6
2
1
IC301
V OUT
T-Bus