R-Y Level Adjustment; Sub Chroma N10/Smpte Adjustment; Burst Gate Pulse Width Adjustment; Ntsc Color Demodulation Adjustment - Sony trinitron PVM-1450QM Service Manual

4. R-Y LEVEL ADJUSTMENT (PVM-1454QM only)
1. Input a component color bar (R-Y, Y, B-Y). (Beta 0 level
signal).
2. From the menu, make the Component Level Beta 0.
3. Connect the oscilloscope probe to IC404 Pin 41 or TP401.
4. Put the unit into service mode.
5. Using
I
R-Y LEVEL COMPONENT
I,
adjust so that the tops
of the wavefonn line up as in the diagram below. (Fig. 13)
30mVmax.
A
B
Fig. 13
D
J.
r
20mV max.
Adjust so that B=D above (20 mV max.) Chec;k that the
difference between D and C is no greater than 30 mV
5. SUB CHROMA N10/SMPTE Adjustment
(PVM-1454QM only)
l. Input a component color bar (R-Y, Y, 8-Y). (SMPTE level
signal).
2. From the menu, make the Component Level N!O/SMPTE.
3 .. Connect the oscilloscope probe to IC404 Pin 30 or TP402.
4. Put the unit into service mode.
5. In the same manner as in 4-5, adjust ISUB CHROMA
NlO/SMPTE!.
6. BURST GATE PULSE WIDTH Adjustment
l. lnput an NTSC color bar.
2. Connect the oscilloscope probes to TP30! (COMP-SYNC)
and Q363 or IC305 Pin l. (Be careful! IC305 Pin l is a
high-impedance line.)
3. Put the unit into service mode.
4. Adjust
I
BGP WIDTH
l
so that the output waveform has the
relationship shown in Fig. 14.
T
IC305 Pin 1
waveform _ ___, __
T=7.B
±
0.2µ$
TP301J
wa,,ro~
Fig. 14
7. VXO Adjustment
1. X'tal 358
PVM-1450QM/1454QM
l) Input an NTSC color bar.
2) Connect the frequency counter to IC305 Pin 21.
3) Put the unit into service mode.
4) Connect the circuit on the right to 1C305 Pin 1.
5) Adjust
l
CRY ST AL 358
l
so that the counter reading meets the
standard below. (You can also just adjust for where the color
flicker stops.)
X'tal 358
Standard level 3.579545
±
20Hz
18K
T
12V
~ ~ ~ ~
.. TOfC3051PfN
Example:
1SS133
(For connecting to Pin l, have the four diodes as close to Pin
l as possible to reduce the length of the wires.)
2. X'tal 443
1) Input a 443 NTSC color bar.
2) Connect the frequency counter to lC305 Pin 21.
3) Put the unit into service mode.
4) Connect to 1C305 Pin l in the same manner as in l -4 ).
5) Adjust Crystal 443 in the same manner as in 1-5).
X'tal 443
Standard level 4.433619
±
20Hz
8. NTSC COLOR DEMODULATION Adjustment
*
The adjustment in 8-1-3) is not necessary for PVM-1454QM.
*
The adjustment in 8-1-4) is not
necessary
for PVM-J450QM.
I. NT 358 PHASE (NORMAL)
I) Input an NTSC color bar.
2) Connect the oscilloscope probe to TP306.
3) Supply 4 VDC to IC305 Pin 4.
4) Put the unit into H/V delay mode.
5) Put the unit into service mode.
6) Adjust PHASE NTSC 358 NOR so that the output waveform
burst section is a straight line. (Fig. 15)
Make this flat.
Fig. 15
2. NT358 PHASE (ACC OFF) (PVM-l 454QM only)
I) Switch ACC Off with the menu.
2) Adjust in the same manner as in 8- l above, but adjust with
J
PHASE NTSC 358 ACC OFF
1-
(Fig. I 5)
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