Yamaha Montage 6, Руководство по обслуживанию

Страница: 53 / 158

■
TEST PROGRAM
53
MONTAGE6/MONTAGE7
1. Measurement condition
1-1. Environment
Perform tests under following conditions.
Ordinary temperature (5°C to 40°C)
Ordinary humidity (20% to 90%)
If the test results does not meet the specifications, check again the tests under such conditions as the ordinary temperature (5°C
to 35°C) and ordinary humidity (45% to 85% relative humidity).
1-2. Power voltage
The power voltage should be the rated voltage as indicated on the name plate.
The AC power should be 50Hz or 60Hz and the capacity should be 500VA or more.
1-3. Measuring instrument
Make sure that the instruments used for inspections have enough accuracy and precision.
Use the instruments with more than 1M-ohms input impedance.
• Level meter (using JIS-C filter)
• Frequency counter (should be capable of measuring to three places of decimals)
• Oscilloscope
• Oscillator
• Distortion meter
1-4. Test jig
Following jigs are required for testing.
• Speaker with amplifier
• MIDI cable
• USB cable (A-B type)
• USB flash drive
• Foot pedal (FC3A, FC4A or FC5)
• Foot controller (FC7)
• Monoral plug (150-ohms load) : Noise level check for the A/D INPUT jacks.
1-5. Terminal condition
Measure the values at the PHONES jack by using a stereo plug unless otherwise specified.
PHONES : Install a measuring plug (L/R ch: 33-ohms load)
A/D INPUT [L/MONO]/[R] : Install a monoral plug
OUTPUT [L/MONO]/[R] (Balanced) : Install the jig (L/R ch: 600-ohms load)
ASSIGNABLE OUTPUT [L]/[R] (Balanced) : Install the jig (L/R ch: 600-ohms load)
When measuring at the OUTPUT BALANCED jacks, the Balance to Unbalance conversion jig is required as shown be -
low. The jig should be connected to the OUTPUT BALANCED jacks as shown below. (In this case, measurement should
be taken at both Hot (+)/Cold (-)).
SW 1
SW 2
Hot (+)
IN
GND
Cold (–)
q
w
600-ohms
GND
Measuring
instrument
q Turn on SW2 and turn off SW1 when measureing Hot (+).
w Turn on SW1 and turn off SW2 when measureing Cold (-).
* If you execute Test No. 25 Factory Set, the setting data and user data will be lost. Be sure to save these data for
backup in advance. (See page 101.)