Yamaha SP2060, Руководство по обслуживанию

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SP2060
54
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INSPECTIONS
Measure the following items by using test No. 1.
1
Gain
1. Measurement Conditions
1-1. Environment
• Normal temperature: 5 to 40 degree
• Normal humidity: 30 to 90 %
1-2. Power Source
The voltage is within
±
10 %.
• U : 120 V
• H : 230 V
• B : 230 V
• O : 230 V
2. ANALOG Test
The ANALOG test is executed by using the test program.
2-1. Preparation
Refer to “TEST PROGRAM 1. Preparation” on page 36~37.
2-2. Measuring conditions
Use following conditions unless otherwise specified.
• 0dBu = 0.775 Vrms
• 0 dBFS = 0 dB, full scale
• Analog output load: 600
Ω
• Cross talk and distortion ratio should be measured with a 80 kHz, -18 dB/octave low pass filter.
• Noise should be measured with a 12.7 kHz, -6 dB/octave low pass filter.
(Use average values instead of effective values for measurement.)
• Oscillator output impedance: 150
Ω
.
2-3. ANALOG Input/Output Test (When WORD CLOCK is INT 96 kHz)
Input analog signal to INPUT A, B terminals and then measure the output signal obtained at OUTPUT 1~6 terminals.
For the details of the measuring procedures, refer to “TEST PROGRAM 3-10. ANALOG Test”.
Conditions for each test No. are as shown below.
Fs MUTE
1
2 96 kHz
96 kHz OFF
ON
Input frequency
1 kHz
Input level
+4 dBu
Specified output level
+4 dBu
Variation width
+4
±
1 dBu
2 Frequency Characteristics
Measure the each frequency response compared with the 1 kHz (0 dB).
Input frequency
20 Hz
40 kHz
Input level
+4 dBu
+4 dBu
Output level (reference)
+4 dBu
+4 dBu
Variation width
-1.0~+0.5 dB
-1.0~+0.5 dB
Test no.