Inspections; Measuring Conditions - Yamaha MSR400 Service Manual

MSR400

■ INSPECTIONS

1.

Measuring conditions

1-1. Measuring voltage:
1-2. Load resistance:
1-3. LEVEL control setting:
1-4. EQ LOW control setting:
1-5. EQ HIGH control setting: Center click position (0)
1-6. Room temperature:
2. Inspections
2-1. Power on muting time:
Check that the muting function is cancelled and the relay turns on in 3±1 seconds after the power switch is turned on.
Also, check the POWER indicator lights up.
2-2. Idling current adjustment:
Adjust VR201 and VR202 so that the voltage between pins 1 and 2 of CN206 and CN207 becomes 1±0.2 mV respectively.
2-3. General inspections:
Measure the following items in condition given below, and check the following values are satisfied.
Items
1 Output power
2 Voltage gain
3 EQ characteristic
4 Frequency response
characteristic
5 DC offset
6 S/N ratio
(with A-weight filter)
7 Gain/Efficiency
(Primary side power consumption)
8 Noise level
(with 20 Hz-20kHz filter)
2-4. Protection circuit test:
Apply DC+5 V (power supply output resistance = 10 kΩ) between pins 1 and 2 of the connector CN209 and check that the relay
turns off within 1 second. Also, check that it returns automatically within 10 seconds when the DC+5 V is shut off.
14
AC 120 V, 60 Hz (U)
AC 230 V, 50 Hz (H, B)
AC 240 V, 50 Hz (A)
AC 220 V, 60 Hz (K)
AC 110 V, 60 Hz (T)
AC 220 V, 50 Hz (O)
LF: 4 Ω / Power capacity 500 W
HF: 16 Ω / Power capacity 200 W
Center click position (+4 dB)
Center click position (0)
24±4 ℃
Conditions
Input
LF LEVEL: Max.
HF LEVEL: Max.
LF –42 dB, 500 Hz input, LEVEL: Max.
HF –34 dB, 5 kHz input, LEVEL: Max.
LF EQ LOW: Min.(Ref.: 55 Hz, EQ LOW: Center)
EQ LOW: Max.(Ref.: 55 Hz, EQ LOW: Center)
HF EQ HIGH: Min.(Ref.: 15 kHz, EQ HIGH: Center)
EQ HIGH: Max.(Ref.: 15 kHz, EQ HIGH: Center)
LF 55 Hz input (Ref.: 500 Hz)
1 kHz input (Ref.: 500 Hz)
2 kHz input (Ref.: 500 Hz)
1 kHz input (Ref.: 6.5 kHz)
HF
2 kHz input (Ref.: 6.5 kHz)
15 kHz input (Ref.: 6.5 kHz)
LF without signal input
HF without signal input
LF 500 Hz input, LEVEL: Max.
HF 5 kHz input, LEVEL: Max.
LF 500 Hz input
HF 5 kHz input
LF LEVEL: Min., grounded with two 600Ω resistance
HF LEVEL: Min., grounded with two 600Ω resistance
Values
Output Typical
1% THD output 230 W
80 W
26 dB
29 dB
(Ref: The gain –3 dB
when the EQ LOW
+3 dB
or HIGH is at the
–3 dB
center click position
as 0 dB) +3 dB
(Ref.: 1 W output) +8 dB
+1 dB
–8 dB
(Ref.: 1 W output) –22.5 dB
–4.5 dB
+7.5 dB
±8 mV
±10 mV
225W output 75 dB
85 W output 70 dB
30 W output 110 W
4 W output 25 W
1 mV
1 mV
Limited
225 W
75 W
26±1.5 dB
29±1.5 dB
–3±1 dB
+3±1 dB
–3±1 dB
+3±1 dB
+8±1 dB
+1±1 dB
–8±2 dB
–22.5±3 dB
–4.5±1 dB
+7.5±2 dB
±8±20 mV
±10±20 mV
70 dB
65 dB
110+10/–30 W
25±10 W
1.7 mV
1.2 mV