Yamaha MX49, Руководство по обслуживанию

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3. Test program list
Test
LCD display Test description, judging conditions, etc.
No.
001 001: Version Displays the ROM Version.
Check the version of ROM (x.xx).
(OK: “B: x.xx”, “M: x.xx”, “W: x.xx” / NG: Otherwise)
002 002: ROM Chk1 Checks the ROM. (Simple check)
Check the ROM that is connected to the CPU.
(Read operation of all address lines and all data bus lines.)
After executing the test, confirm that “OK” is displayed on the LCD.
(OK: “OK” / NG: “NG”)
Note: If the test no.6 (All memory simple check) is executed, this test can be skipped.
003 003: RAM Chk1 Checks the RAMs. (Simple check)
Check the RAMs that are connected to the CPU.
(Read/Write operation of all address lines and all data bus lines.)
After executing the test, confirm that “OK” is displayed on the LCD.
(OK: “OK” / NG: “NG”)
Note: If the test no.6 (All memory simple check) is executed, this test can be skipped.
004 004: Wave ROM Chk1 Checks the wave ROMs. (Simple check)
Check the wave ROMs that are connected to the tone generator.
(Read operation of all address lines and all data bus lines.)
After executing the test, confirm that “OK” is displayed on the LCD.
(OK: “OK” / NG: “NG”)
Note: If the test no.6 (All memory simple check) is executed, this test can be skipped.
005 005: Effect RAM Chk1 Checks the effect RAMs. (Simple check)
Check the effect RAMs that are connected to the tone generator.
(Read/Write operation of all address lines and all data bus lines.)
After executing the test, confirm that “OK” is displayed on the LCD.
(OK: “OK” / NG: “NG”)
Note: If the test no.6 (All memory simple check) is executed, this test can be skipped.
006 006: All Memory Chk Checks all the ROMs and RAMs. (Simple check)
Check all the ROM and RAMs connected to the CPU and the wave ROMs and
the effect RAMs connected to the tone generator.
After executing the test, confirm that “OK” is displayed on the LCD.
(OK: “OK” / NG: “NG: ROM RAM Wave FX”)
(In case of NG, either of them becomes “NG”.)
Note: If the test result is OK, the test no.2 through no.5 can be skipped.
007 007: Pitch Chk Checks the pitch accuracy. While sound is output, “ON” is displayed on the LCD.
Connect a frequency counter to the [PHONES] terminal. (L or R)
Confirm that sound is produced with 441Hz ±0.2Hz sine wave.
008 008: Output R Chk Checks the output level R. While sound is output, “ON” is displayed on the LCD.
•
Output Level and Cross Talk Level (PHONES)
Connect a level meter to the [PHONES] terminal (L and R).
Confirm each output level is as follows.
PHONES L: -62.0dBu or less
PHONES R: -4.6dBu ±2dB
• Output Level and Cross Talk Level (OUTPUT)
Connect the level meter to the OUTPUT jack ([L/MONO] and [R]). Insert the jacks to both
the [L/MONO] and [R] terminals at the same time.
Confirm each output level is as follows.
OUTPUT L: -62.0dBu or less
OUTPUT R: +1.4dBu ±2dB
• Volume Attenuation
Connect the level meter to the OUTPUT terminal ([L/MONO] and [R]). Insert the jacks to both
the [L/MONO] and [R] terminals at the same time.
Set the [MASTER VOLUME] knob to minimum, and measure the attenuation level.
Confirm the output level is as follows.
OUTPUT R: -62.0dBu or less
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MX61/MX49