— 5 —
SERVICE ADJUSTMENTS (Continued)
MULTI-SOUND SECTION ADJUSTMENTS
Note: Multi-Sound Section must be adjusted after
A101 (U/V Tuner), IC3401 (MTS Decoder), Digital
Module or IC802 (EEPROM) is replaced.
INPUT LEVEL ADJUSTMENT
1. Connect a signal to the analog antenna terminal with
audio of 1 KH
Z 100% modulation.
2. Turn off the receiver and disconnect the AC power cord
(AC 120V line).
3. Connect voltmeter (RMS) to TP317 and ground on the
Main PC board.
4. While pressing the VOLUME – key, reconnect the AC
power cord. The Service Menu will now appear.
5. Select NO. 080 (ATT: MTS Input Level) with the
or key.
6. Adjust the + or – key for a voltmeter reading of 400 ±
20 mVrms at TP317.
Figure 2. Separation Adjustments
SEPARATION ADJUSTMENT
7. Turn off the receiver and disconnect the AC power cord
(AC 120V line).
8. Connect oscilloscope CH1 to TP317 and CH2 to TP318
and ground.
9. Connect an MTS TV/Stereo generator to antenna terminal.
10. While pressing the VOLUME – 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. 082 (WDB: Wide Band) with the or key.
13. Adjust the + or – key for minimum low frequencies at
TP317. See Figure 2.
14. Select 4 KHz audio frequency and Right modulating signal.
15. Select NO.0 81 (SPC: Spectral) with the or key.
16. Adjust the + or – key for minimum high frequencies at
TP318. See Figure 2.
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.
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