Sanyo DS27910 Service Manual page 9

FOCUS ADJUSTMENT
1. Connect a color-bar generator to the antenna terminals
and select a crosshatch pattern.
2. Set the picture controls to the Sports levels.
3. Select a vertical line at the center of the screen and
adjust the H focus control for best focus.
4. Select a horizontal line at the top of the screen and
adjust the V focus control for best focus.
5. Repeat steps 3 and 4 for best focus.
Focus
V
Figure 7. Focus controls location
Adjust the focus of this line using V focus control.
Adjust the focus of this line using H focus control.
Figure 8. Focus adjustment
SOUND ADJUSTMENT
1. Connect a color-bar generator to the antenna terminals
with audio signal of 1KHz at 100% modulation.
2. Set the picture controls to the Sports levels
3. Connect oscilloscope + lead to
and – lead to ground.
4. Turn off the receiver and disconnect the AC power cord
(AC 120V line).
5. While pressing the Menu key, reconnect the AC power
cord. The Service Menu will now appear.
6. Select NO. 45 FL (FM Level) with the
7. Adjust the data with the + or – key for an oscilloscope
reading of 0.693 ± 10% VP-P at TP21.
8. Press the MENU key to turn off the Service Menu display
and disconnect the oscilloscope from the chassis.
Figure 9.
H
Screen
TP21 (pin 75 of IC101)
or key.
0.693 ± 10% VP-P
— 9 —
MULTI-SOUND SECTION ADJUSTMENTS
Note: Multi-Sound Section must be adjusted after
IC101 (Signal Processor), IC3401 (MTS Decoder), or
IC802 (EEPROM) is replaced.
INPUT LEVEL ADJUSTMENT
1. Connect a signal to the antenna terminals with audio of
1 KH 100% modulation.
Z
2. Turn off the receiver and disconnect the AC power cord
(AC 120V line).
3. Connect voltmeter (RMS) to
4. While pressing the Menu key, reconnect the AC power
cord. The Service Menu will now appear.
5. Select NO. 60 ATT (Attenuation) with the
6. Adjust the + or – key for a voltmeter reading of 400 ± 20
mVrms at TP317.
SEPARATION ADJUSTMENT
7. Turn off the receiver and disconnect the AC power cord
(AC 120V line).
8. Connect oscilloscope CH1 to
and ground.
9. Connect an MTS TV/Stereo generator to antenna terminal.
10. While pressing the Menu key, reconnect the AC power
cord. The Service Menu will now appear.
11. Select pilot, 300Hz audio frequency and Left modulating
signal.
12. Select NO. 61 WDB (Wideband) with the
13. Adjust the + or – key for minimum low frequencies at
TP317. (See Figure 10.)
14. Select 4 KHz audio frequency and Right modulating signal.
15. Select NO. 62 SPC (Spectral) with the
16. Adjust the + or – key for minimum high frequencies at
TP318. (See Figure 10.)
Repeat adjustments (steps 11–16) until no further decreases
in amplitude can be obtained. Press the MENU key to turn
off the Service Menu display.
Minimize L leakage
TP317 (R)
TP318 (L)
Figure 10. Separation Adjustments
PURITY AND CONVERGENCE ADJUSTMENTS
Purity and Convergence have been aligned at the factory.
No re-alignment is necessary.
TP317 and ground.
or
TP317 and CH2 to TP318
or
or key.
300Hz
Minimize R leakage
4KHz
key.
key.