Yamaha Montage 6, Руководство по обслуживанию

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MONTAGE6/MONTAGE7
LCD display
Test items and judging conditions
19 : MUTE (DAC) Checks whether the DAC MUTE for the DAC IC’s output works properly or not.
1) Connect the level meter to an output jack.
2) Set the [MASTER VOLUME] control to the maximum position.
3) Press the [ENTER] button to produce the sine wave sound. “ OFF ” is shown on the LCD.
4) Press the [ENTER] button to activate the DAC MUTE circuit.
“ ON ” is shown on the LCD, and all the output from the PHONES and OUTPUT jacks are muted.
5) Press the [ENTER] button to cancel the DAC MUTE circuit.
“ OFF ” is shown on the LCD and the sound is produced.
6) Check the output level when the MUTE is at OFF.
Measure the output level and confirm that the measured values are within the specified range.
[OUTPUT (Balanced)]
(600
-ohms
load)
OUTPUT L/MONO (HOT/COLD): +2.7 dBu±2 dB
OUTPUT R (HOT/COLD): +2.7 dBu±2 dB
[ASSIGNABLE OUTPUT (Balanced)] (600 -ohms load)
OUTPUT L (HOT/COLD): +2.7 dBu±2 dB
OUTPUT R (HOT/COLD): +2.7 dBu±2 dB
7) Check the output level when the MUTE is at ON.
Measure the output level and confirm that the measured values are within the specified range.
[OUTPUT (Balanced)] (600 -ohms load)
OUTPUT L/MONO (HOT/COLD): -89 dBu or less
OUTPUT R (HOT/COLD): -89 dBu or less
[ASSIGNABLE OUTPUT (Balanced)]
(600
-ohms
load)
OUTPUT L (HOT/COLD): -89 dBu or less
OUTPUT R (HOT/COLD): -89 dBu or less
8) Press the [EXIT] button, and testing is finished and the display is changed to the test item selection
screen.
20 : ROM Checks eMMC (IC403), SUB CPU ROM (IC502) and WAVE ROM (IC601, IC604, IC605, IC607).
(This check takes about 13 seconds.)
1) Press the [ENTER] button, and then the result is shown on the LCD.
Until the result is given, “Now Executing...” is shown.
If no problem is found:
OK
If any problem is found : NG
2) Confirm that “ OK ” is shown for all items on the LCD.
3) When OK/NG of the test result is shown, testing is finished and the display is changed to the test
item selection screen.
21 : RAM
Checks MAIN CPU RAM (IC401), EFFECT RAM (IC803, IC805) and WAVE RAM (IC602).
1) Press the [ENTER] button, and then the result is shown on the LCD.
If no problem is found: OK
If any problem is found : NG
2) Confirm that “ OK ” is shown for all items on the LCD.
3) When OK/NG of the test result is shown, testing is finished and the display is changed to the test
item selection screen.