21
HCD-VX888
Note:
Clear RF signal waveform means that the shape “
◊
” can be
clearly distinguished at the center of the waveform.
RF signal waveform
E-F Balance (1 Track jump) Check
Procedure:
1.
Connect an oscilloscope to TP (TEO) and TP (DVC).
2.
Turned Power switch on.
3.
Load a disc (YEDS-18) and playback the number five track.
4.
Press the
u
button. (Becomes the 1track jump mode.)
5.
Confirm that the level B and A (DC voltage) on the oscilloscope
waveform.
1 track jump waveform
Specification level:
x
100=less than
±
22%
After check, remove the lead wire connected in step 1.
Connect frequency counter to test point (XPCK) with lead wire.
3.
Put the disc (YEDS-18) in to play the number five track.
Confirm that reading on frequency counter is 4.3218MHz.
oscilloscope
BD board
TP (TEO)
TP (DVC)
+
–
A
B
+
–
frequency counter
Adjustment Location :
[ BD BOARD ] — SIDE B —
IC103
IC101
TP
(RFDC)
TP
(FEO)
TP (TEO)
TP
(DVC)
TP
(RFAC)
17
TP
(VC)
TP
(XPCK)
TP
(FEI)
VOLT/DIV : 200mV
TIME/DIV : 500ns
level : 1.1
±
0.3Vp-p
0V
Center of
waveform
B
Symmetry
A (DC voltage)
level=1.3
±
0.6Vp-p
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