Yamaha MODX6 Service Manual page 44

MODX6/MODX7
LCD display
14 : OUTPUT-R (-12dB)
15 : A/D -> D/A (MIC)
44
Checks each output level from the R channel of the jacks.
1) Connect the frequency counter to the PHONES jack at R.
2) Connect the level meter to an output jack.
3) Set the [MASTER VOLUME] control to the maximum position.
4) Press the [ENTER] button to produce the 1kHz sine wave sound. "ON" is shown on the LCD.
5) Measure the frequency and confirm that the measured value is 1 kHz ± 0.2Hz.
6) Measure the output level and confirm that the measured values are within the specified range.
[PHONES] (33 -ohms
load)
PHONES L: -62.0 dBu or less PHONES R: -3.8 dBu±2 dB
[OUTPUT] (10k -ohms
OUTPUT L/MONO : -72.0 dBu or less R : +1.6 dBu±2 dB
7) Set the [MASTER VOLUME] control to the minimum position.
8) Measure the output level and confirm that the measured value is within the specified range.
-ohms
[OUTPUT] (10k
R : -72.0 dBu or less
9) Press the [EXIT] button, and testing is finished and the display is changed to the test item selection
screen.
Checks the signal path from the A/D input to D/A output. (Gain is set to LINE due to Default.)
1) Connect the level meter to [OUTPUT] jack.
(Connect the plug to both jacks of L/MONO and R.)
2) Set the [MASTER VOLUME] control to the maximum position.
3) Press the [ENTER] button. "L-Channel input OFF" is shown on the LCD.
4) Insert the monaural plug for residual noise measurement (150
PUT [R] jacks.
5) Connect an oscillator to the A/D INPUT [L/MONO] jack. "ON" is shown on the LCD.
6) Input a 1kHz, -36dBu sine wave.
7) Set the A/D INPUT [GAIN] knob to the maximum position.
8) Measure the output level and confirm that the measured values are within the specified range.
[OUTPUT] (10k -ohms
L/MONO : +1.6 dBu±2 dB
9) Set the A/D INPUT [GAIN] knob to the minimum position.
10) Disconnect the plug. "OFF" is shown on the LCD.
11) Insert the monaural plug for residual noise measurement (150
PUT [L/MONO] jacks.
12) Connect an oscillator to the A/D INPUT [R] jack.
13) Input a 1kHz, -36dBu sine wave.
14) Set the A/D INPUT [GAIN] knob to the maximum position.
15) Measure the output level and confirm that the measured values are within the specified range.
[OUTPUT] (10k -ohms
L/MONO : -62.0 dBu or less
16) Set the A/D INPUT [GAIN] knob to the minimum position.
17) Insert the monaural plug for residual noise measurement (150
PUT [L/MONO][R] jacks.
18) Set the A/D INPUT [GAIN] knob to the maximum position.
19) Measure the residual noise level and check that the measured values are within the specified range.
[OUTPUT] (10k -ohms
L/MONO : -64.0 dBu or less
20) Press the [EXIT] button, and testing is finished and the display is changed to the test item selection
screen.
Test items and judging conditions
load)
load)
load)
R : -62.0 dBu or less
load)
R : +1.6 dBu±2 dB
load)
R : -64.0 dBu or less
-ohms resistor end) to the A/D IN-
-ohms resistor end) to the A/D IN-
-ohms resistor end) to the A/D IN-