Yamaha spx2000 Service Manual page 39

QQ
3 7 63 1515 0
8. WORD CLOCK test
The external oscillator OUT -> WORD CLOCK IN is
counted by PLLP2 for automatic check.
(Fs=44.1/48/88.2/96kHz)
The lock condition of PLL is checked by reading the
UNLOCK signal when the clock has been stabilized after
the FS was changed (after about 200 ms).
The unlock condition of PLL is checked by pulling off
the cable connected to WORD CLOCK IN.
Preparation
Connect the external oscillator and WORD CLOCK IN
of the main unit.
Set the output clock of the external oscillator to 44.1kHz.
Example of execution screen
WORD CLOCK
When testing starts, "testing..." appears on the screen.
When "Fs=48kHz OK?" appears on the screen, change
the output clock of the external oscillator to Fs=48kHz.
TE
When preparation is completed, press the [NEXT]
L 13942296513
switch.
To cancel testing in this stage, press either [UNDO] or
[BACK] switch.
When testing starts, "testing..." appears on the screen.
When "Fs=88.2kHz OK?" appears on the screen, change
the output clock of the external oscillator to Fs=88.2kHz.
When preparation is completed, press the [NEXT]
switch.To cancel testing in this stage, press either
[UNDO] or [BACK] switch.
When testing starts, "testing..." appears on the screen.
When "Fs=96kHz OK?" appears on the screen, change
the output clock of the external oscillator to Fs=96kHz.
When preparation is completed, press the [NEXT]
switch.To cancel testing in this stage, press either
[UNDO] or [BACK] switch.
When testing starts, "testing..." appears on the screen.
www
When "WC disconnect!" appears on the screen,
disconnect the WORD CLOCK OUT signal which is
.
connected IN -> OUT.
When preparation is completed, press the [NEXT]
switch.To cancel testing in this stage, press either
[UNDO] or [BACK] switch.
http://www.xiaoyu163.com
OK
x ao u163
y
i
http://www.xiaoyu163.com
2 9
8
"OK is displayed when the WORD CLOCK test ends
with a satisfactory result and "NG" when it ends with an
abnormality detected.
Caution
1) Various types of FS for PLL LOCK test are produced
by the external oscillator.
FS=44.1kHz, 48kHz, 88.2kHz, 96kHz
9. LCD test
The LCD back-light (LED) is turned on in 3 colors
respectively and checked visually.
The entire LCD screen is displayed in black and white
alternately and checked visually.
Example of execution screen
"Red" appears on the screen and the LCD back-color
lights in red.
"Green" appears on the screen and the LCD back-color
lights in green.
Q Q
3 6 7 1 3 1 5
"Blue" appears on the screen and the LCD back-color
lights in blue.
"White" appears on the screen and the LCD back-color
lights in white.
If LCD back-color check result is satisfactory, press the
[NEXT] switch but if it is not, press the [BACK] switch
to make this test end.
When the above four colors have been confirmed and
the [NEXT] switch is pressed at the fourth color, dots
on the entire LCD screen are turned on and off repeatedly.
Check that the entire screen is displayed in black and
white.
Check that no dot is missing on the entire screen.
Check that the display contrast is in good condition.
When the check results of above 3 items are satisfactory,
press the [NEXT] switch but if they are not, press the
[BACK] switch.
"OK" appears on the screen when the LCD test ends
co
with a satisfactory result and "NG" when it ends with an
.
abnormality detected.
9 4 2 8
PA
O
0 5 8 2 9 9 4 2 8
m
SPX2000
9 9
9 9
39