Sony Multiscan GDM-2036S Service Manual page 34

GDM-2036S
(a). V. LIN correction waveform
The sine wave output from pin @ of IC202 is input to IC9
(D/A) as the reference signal. It is adjusted the level by the
signal from CPU (IC3) to obtain the V. LIN correction
waveform to pin
CD
ofICl9.
(b). V. LIN BAL correction waveform
The parabola wave output from pin @ of IC202 is level
shifted by IC25. The signal is input to IC9 (D/A) as the
reference signal. It is adjusted the level by the signal from
CPU (IC3) to obtain the V. LIN BAL correction waveform to
pin (j) of IC20.
(d). V. SIZE correction waveform
The signal which is added the V. LIN, V. LIN BAL correction
waveforms mentioned above to the SAW wave amplified pin
®
output of IC201 by IC25 is referred to the reference signal.
Its signal is input to pin
®
of IClO. And it is adjusted the level
by the signal of CPU (IC3) to obtain the V. SIZE correction
waveform to pin
CD
of IC22. And after being added the V.
CENT correction voltage mentioned above to this signal, it is
sent to the D3 board as the V. SIZE correction waveform
from pin@ of connector N-!.
3-8-5-2. H. SIZE correctIon waveform
The signal according to the horizontal oscillation frequency is
output by the CPU (IC3) control from pin@ of IC4 (D/A).
The maximum value of this voltage is limited by RV3 and
RV4. This signal is the reference signal, it is input to ICIO
(D/A), adjusting the voltage with the CPU (IC3) signal. After
being added this voltage to the above voltage, the voltage
adjusted with RVlO is sent out to the D3 board as the H. SIZE
correction voltage from pin @ of connector N-l.
The block diagram of H. SIZE correction waveform circuit is
as shown in Fig. 3-11.
RV3 RV4
rf
Fig. 3-11 H. SIZE correction block
RVIO
N-I
PIN@)
3-8-5-3. H. CENT correction waveform
The signal of CPU (IC3) is input to IC4 (D/A) to adjust the
voltage. And it is sent out to the D3 board as the H. CENT
correction voltage from pin @ of connector N-!. The block
diagram of H. CENT correction waveform circuit is as shown
in Fig. 3-12.
H.cent
D.C
t--_ _ _ _ _
-o
N - 1
'--~--'
PIN@)
Fig.3-12 H. CENT correction block
3-8-5-4. PIN correction waveform
The parabola wave of pin correction is output to pin @ of
connector N-!. This waveform includes the key correction
waveform. And the V.lin and V.lin bal correction waveforms
are added to compensate the pin distortion by the V. lin
adjustment. The block diagram of pin correction waveform
circuit is as shown in Fig. 3-13.
(a). KEY correction waveform
The SAW wave amplified the output of pin
®
of IC201 by
IC25 is referred to the reference signal. It is input to IC9
(D/A). This signal is adjusted the level by the signal of CPU
(IC3) to obtain the key correction waveform to pin (j) oflC17.
(b). PIN correction waveform
First, The V. lin correction waveform at 3-8-5-I(b) is delayed
by IC29, and the signal is added the V. lIN BAL correction
waveform at 3-8-5-l{b) by IC26. And the signal is added the
parabola wave of pin @ of IC202 and the key correction
waveform at 3-8-5-4{a). The resulting signal is referred to the
reference signal, inputting to IClO (D/A). This signal is
adjusted the level by the signal of CPU (IC3), sent out to the
D3 board as the PIN correction waveform from pin
@
of
connector N-!.
3-8-5-5. KEY BAL, PIN BAL correction waveforms
The SAW wave amplified the output of pin
®
of IC201 by
IC25 is referred to the reference signal. The signal is input to
IC9 (D/A). This signal is adjusted the level by the signal of
CPU (IC3) to obtain the KEY BAL correction waveform to
pin (j) of ICI8.
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