Yamaha PSR-S750, Service Manual

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61
PSR-S750/PSR-S950
Test No. LCD display Test descriptions, judging conditions, etc.
38 038 : Backup ROM Check2 Checking the BACKUP ROM connected to the CPU bus. (Complete check)
Check that
“Backup ROM Check2 OK” is displayed on the LCD.
It will take about 1 minute for the check.
When the result is NG:
BACKUP (IC21) NG
39 039 : Wave ROM Check2 Checking the WAVE ROM connected to the TG bus. (Complete check)
Check that
“Wave ROM Check2 OK” is displayed on the LCD.
It will take about 2 minutes, 47 seconds for the check.
When the result is NG:
Wave1 (IC302, 308) NG
40 040 : Effect RAM Check2 Checking the Effect RAM connected to the TG bus. (Complete check)
Check that
“Effect RAM Check2 OK” is displayed on LCD.
It will take about 45 seconds for the check.
When the result is NG:
Effect1 (IC301) NG
43 043 : Factory Set If the Factory Set is executed, Internet setup will be lost.
Initializing the entire data to reset to the initial factory setup.
* Only the fl ag for initialization is raised in this stage and the actual initialization will be ex-
ecuted when the power is turned on the next time.
Check that “Factory Set OK” is displayed on LCD.
After executing this Factory Set, make sure to execute the test No. 44 “Test Exit”.
Do not turn off the power until the main screen is indicated after turning on the
power the next time.
44 044 : Test Exit This will leave the test program and change to the play mode.
Do not turn off the power until the main screen is indicated after executing the
Test Exit.
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Other Tests
AUX IN
Check that the output is as shown in the following table when signals are input to the AUX IN.
INPUT
OUTPUT
OUTPUT (10 k Ω load) PHONES (33 Ω load)
L/L+R R L R
AUX IN L: Sine wave (1 kHz, 0 dBu)
R: No input
+7.4 ± 2 dBu -50.0 dBu or less +1.8 ± 2 dBu -40.0 dBu or less
AUX IN L: No input
R: Sine wave (1 kHz, 0 dBu)
-50.0 dBu or less +7.4 ± 2 dBu -40.0 dBu or less +1.8 ± 2 dBu
Noise Level Check
Connect the level meter (with JIS-C fi lter) to the L/R of the [PHONES/OUTPUT] jack. (33 ohms load)
Set the [MASTER VOLUME] to the maximum level and check the noise level.
· PHONES L, R: –90 dBu or less