Yamaha RIO3224-D Service Manual page 72

Rio3224-D
2-2. Vari pitch sound signal test
Input an analog signal from CH1 INTPUT and measure the
output signal from the CH1 OUTPUT.
Gain
WORD Input
CLOCK Frequency
1
42.336 kHz
1 kHz
2
100 kHz
Audibly check for over 15 seconds or longer and confi rm that
there is no sound interruption or distortion in the GAIN MIN
mode.
2-3. INPUT 1-32 GAIN MIN & MAX
Take measurement at INPUT 1–16 and then INPUT 17–32.
For the switching procedure refer to Test Program (p. 47).
A. GAIN MIN
1 GAIN
(INPUT 1–16 are already measured and can be omitted)
Input
Input Level
Frequency
1 kHz +10 dBu
2 Frequency characteristic
Parameters: 1 kHz is used as a reference of the permissible
range.
(INPUT 1–16 are already measured and can be
omitted)
Input
Input Level
Frequency
40 kHz +10 dBu
3 Distortion
(INPUT 1–16 are already measured and can be omitted)
Input
Input Level
Frequency
1 kHz +4 dBu
4 Residual noise
Short INPUT to be measures with 150Ω.
(INPUT 1–16 are already measured and can be omitted)
Permissible
Range
-80 dBu or less
5 Level difference between channels
Confi rm that the range of difference in the gain measured in
item 1 above is as follows.
Permissible
Range
Within 1 dB
72
Specifi ed
Input Permissible
Output
Level Range
Level
–62 dBu +4 dBu +4±2 dBu
Specifi ed Permissible
Output Level Range
+4 dBu +4±2 dBu
Permissible
Range
-1.5 – 0.5 dB
Permissible
Range
0.05 % or less
B. GAIN MAX
1 Gain (INPUT 1–32)
Input
Input Level
Frequency
1 kHz -62 dBu
2 Distortion (INPUT 1–32)
Input
Output Level
Frequency
1 kHz +4 dBu
3 Noise level EIN (INPUT 1–32)
Parameters: Short INPUT to be measures with 150Ω.
Permissible
Range
-61 dBu or less
If the measured value is not within the above permissible
range, check that "measured value – (gain at 1 kHz) ≦ -127" is
obtained.
4 Level difference between channels
Confirm that the range of difference in the gain measured in
item 1 above is as follows.
Permissible
Range
Within 2 dB
C. Phantom power (INPUT 1, 9, 17, 25)
With No.2 and No.3 pins of XLR shorted and 10 kΩ load
connected between No.2 and No.1 pins, check that the voltage
is as follows when the +48 key is turned on.
Permissible Range
DC 33.6 – 36.1 V
Also, check that discharging starts quickly when the +48 key is
turned off.
Use INPUT 1, 9, 17 and 25 as representing others.
Specifi ed Permissible
Output Level Range
+4 dBu +4±2 dBu
Permissible
Range
0.12 % or less