21
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 oscilloscope to TP (TEO) and TP (VC) board.
2.
Turned Power switch on.
3.
Load a disc (YEDS-18) and playback the number five track.
4.
Press the
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%
6.
After check, remove the lead wire connected in step 1.
RF PLL Free-run Frequency
Procedure :
1.
Connect frequency counter to test point (XPCK) with lead wire.
2.
Turned Power switch on.
3.
Put the disc (YEDS-18) in to play the number five track.
Confirm that reading on frequency counter is 4.3218MHz.
VOLT/DIV : 200mV
TIME/DIV : 500ns
level : 1.45
±
0.3Vp-p
oscilloscope
BD board
TP (TEO)
TP (VC)
+
–
0V
Center of
waveform
B
Symmetry
A (DC voltage)
level=1.3
±
0.6Vp-p
A
B
+
–
frequency counter
BD board
TP (XPCK)
Содержание HCD-VX77
Страница 28: ...HCD VX77 VX77J 28 28 7 3 PRINTED WIRING BOARD BD SECTION See page 23 for Circuit Boards Location ...
Страница 35: ...HCD VX77 VX77J 35 35 7 10 SCHEMATIC DIAGRAM MAIN 1 3 SECTION See page 59 for IC Block Diagrams ...
Страница 37: ...HCD VX77 VX77J 37 37 7 12 SCHEMATIC DIAGRAM MAIN 3 3 SECTION See page 34 for Printed Wiring Board ...
Страница 39: ...HCD VX77 VX77J 39 39 7 14 SCHEMATIC DIAGRAM POWER AMP SECTION ...
Страница 43: ...HCD VX77 VX77J 43 43 7 18 SCHEMATIC DIAGRAM LEAF SW SECTION ...
Страница 45: ...HCD VX77 VX77J 45 45 7 20 SCHEMATIC DIAGRAM DRIVER SECTION See page 58 for IC Block Diagrams ...
Страница 47: ...HCD VX77 VX77J 47 47 7 22 SCHEMATIC DIAGRAM TRANS SECTION ...