NAD S400, Руководство по обслуживанию

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12) With the audio AC-voltmeter connected as in procedure #9, select 0 db range for both channels.
Connect an RF signal generator to ANTENNA port # 1 and set to:
Amplitude = 65 dBu
Pilot tone = on (19 kHz @ 10%)
Modulation = 100% (including pilot tone) [1kHz @ +/- 75 kHz L+R and L-R].
Frequency = 98,000 MHz.
13) Set the S400 as the following:
Press the IF -button to select IF WIDE .
Press the
ANTENNA
-button and select
ANTENNA 1
.
Press the MONO/MUTE -button to MUTE ON STEREO .
Press the BLEND -button to BLEND OFF.
Press the BANDWIDTH -button to BANDWIDTH WIDE.
Tune the S400 to 98.00 MHz.
14) Check that the audio output is approximately 0 dB +/- 1 dB (775 mV rms) in both right and left output
jacks.
1. Turn the variable capacitor C37 so that the capacitor fins do not mesh, then switch off the modulation in the right side of the
RF signal generator. Adjust L12 until minimum audio output is measured in the right side. Record this minimum output
level .
2. Switch on the modulation in the right side of the RF signal generator. Switch off the modulation in the left side of the RF
signal generator. Adjust L12 until minimum audio output is measured in the left side. Record this minimum output level .
Use the side with the worst channel separation to adjust L12, by repeating the above two steps.
After adjusting L12 adjust C37 to minimum output level (maximum channel separation).
Channel separation should be 45 dB (+/- 5 dB).
15) Press the IF -button to select IF NARROW .
Check that the channel separation drops approximately 10 dB (+/- 5dB) at the audio output jacks.
16) Press the BLEND -button to select BLEND ON .
Check that the channel separation drops to approximately 15 dB. (+/- 3 dB) at the audio output jacks.
Remove the audio AC-voltmeter from the audio output jacks, as well as the RF signal generator
form the antenna port.
17) Set the S400 to default settings for the tuner as the following:
Press the IF -button to select IF WIDE .
Press the ANTENNA -button and select ANTENNA 1 .
Press the MONO/MUTE -button to MUTE ON STEREO .
Press the BLEND -button to BLEND OFF.
Press the BANDWIDTH -button to BANDWIDTH WIDE.
After 10 sec. the settings will be stored.
NAD S400