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5.
STEREO SEPARATION ALIGNMENT
1. Set the FM SG to provide I kj.LVat 98 MHz. Tune the receiver to the same frequency so that
the center tuning meter pointer indicates its center.
2. Turn the FM SG modulation off (with the pilot signal turned off), connect a frequency
counter to test point J310, and adjust R311 so that the frequency counter may precisely
read 19 kHz.
3. Modulate the FM SG with stereo composite signal consisting only of subchannel signal (of
course a pilot signal must be included).
4. Adjust the trimming resistor R301 for maximum and same separation in both channels.
6.
MUTING CIRCUIT ALIGNMENT
1. Connect a VTVM across the resistor R363 and adjust the resistor R363 until the meter
reads 0.75V DC at no signal.
2. Set the FM SG to provide I kJ1V at 98 MHz and tune the receiver to the same frequency
correctly.
3. Turn on MUTI NG push switch. Shift the FM signal generator frequency to plus and minus
and note both plus and minus shifted frequencies at which undesirable audio side responses
are muted out. Adjust the R363 so that the same shifted frequencies mute the undesirable
side response.
4. Adjust R362 for proper frequency shift at which the muting circuit operates.
7.
DOLBY FM TAPE OUTPUT SETTING
1. Set the modulation of FM SG to 400 Hz, 50% (±37.5 kHz Dev.)
2. Set the FM SG to provide 1 kJ1V at 98 MHz. Tune the receiver to the same frequency so
that the center tuning meter pointer indicates its center.
3. Turn on DOLBY FM push switch. Set the semifixed resistors RC01 and RC02 so that the
output of the TAPE OUTPUT terminals Rand L become 580 mVat VTVM.
8.
AUDIO ADJUSTMENT
1. Voltage adjustment
Connect a DC voltmeter between pin terminal 804 and 805, and adjust the trimming
resistor R806 for 35V DC.
2. Main Amplifier DC off--set alignment
Connect a DC voltmeter with 0.5 or 1 V range between the speaker terminals and adjust the
trimming resistor R707 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 speakerterminals.
3. Idle-current adjustment
Connect a VTVM between pin terminals 708 and 710. Next, adjust the trimming resistor
R719 so the VTVM reads10mV DC. Repeat the same procedure for the other channel.
4. Check DC off-set voltage aligned in the procedure 2 and if any DC output is observed on the
DC voltmeter, adjust the R707 again for "zero" output.
5. Phono-amplifier adjustment
Connect an oscilloscope to the TAPE OUT jacks and an audio signal generator to the
PHONO jacks. Place the selector switch in the PHONO position. Increase 1 kHz audio signal
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.
4
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