L or R channel (of course, the pilot signal must be included).
3. Adjust the trimming resistor R301 for maximum and same separation in both channels.
19.2 Muting Circuit Alignment
1. Connect a VTVM to the tap of the resistor R363 and adjust the resistor R363 until the
meter reads 0.75V DC at no signal.
2. Set an FM signal generator to provide 1KuV at 98MHz and tune the receiver to the
same frequency correctly.
3. Turn the MUTING pushswitch on. Shift the FM signal generator frequency higher and
lower and note both higher and lower shifted frequencies at which undesirable audio side
responses are muted out. Adjust R363 so that the same shifted frequencies mute the undesirable
audio side responses.
4. Adjust R362 for preferred frequency shift at which the muting circuit operates.
20. AUDIO ADJUSTMENT
20.1 Automatic Voltage Regulator Adjustment
Connect a DC voltmeter between pins J804 and J805, and adjust the trimming resistor R809
for 35V DC.
20.2 Main Amplifier DC Offset Alignment
Connect a DC voltmeter with 0.5 or 1V range between the speaker terminals and adjust the
trimming resistor R713 for "zero" DC output on the meter.
Repeat the same procedure for the other channel.
Note: During this alignment no load should be connected to the speaker terminals.
20.3 Idle-Current Adjustment
Connect a VTVM between pins J702 and J708. Next, rotate the trimming resistor R740 fully
counterclockwise, then rotate it clockwise until the VTVM reads 15mV DC (75mA).
Repeat the same procedure for the other channel.
Note: During this alignment no load should be connected to the speaker terminals.
20.4 Main Amplifier DC Offset Re-Alignment
Check the DC offset voltage aligned in the Sec. 20.2 above. If any DC output is observed on
the DC voltmeter, adjust R713 again for "zero" output.
20.5 Phono-Amplifier Adjustment
Connect an oscilloscope to the TAPE MONITOR OUT jacks and an audio signal generator to
the PHONO jacks. Place the selector switch in the PHONO position. Increase the 1kHz audio
signal level gradually until a slight clipping on top of the sine wave is observed on the
oscilloscope. Adjust the trimming resistor R408 for equal clipping level.
For the other channel, adjust R409.
21. DOLBY ALIGNMENT PROCEDURE
Prior to the adjustment, turn the PLAY CAL and REC LEVEL controls all the way to the
right and the SELECTOR switch to the CD-4/AUX position. Use the CD-4/AUX and TAPE
MONITOR OUT jacks for the signal input and output.
21.1
(1) Set the DOLBY switch to the RECORD I position.
(2) Adjust the semi-fixed resistor R653 for maximum source voltage of the field-effect
transistor H611.
(3) Connect J620 and J613 to the ground.
www.freeservicemanuals.info
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