11
XP-EV500/EV500N/EV501R
SECTION 4
ELECTRICAL CHECKING
The CD section adjustments are done automatically in this set.
In case of operation check, confirm that RF level.
Precautions for Check
1.
Perform check in the order given.
2.
Use YEDS-18 disc (Part No.: 3-702-101-01) unless otherwise
indicated.
3.
Power supply voltage requirement : DC4.5 V in DC IN jack.
(J201)
VOLUME button
: Minimum
HOLD switch
: OFF
Checking Location:
– MAIN board (SIDE B) –
RF Level Check
Condition:
• Hold the set in horizontal state.
Connection:
Procedure:
1.
Connect the oscilloscope to the test points TJ401 (RF) and
TJ403 (RF GND) on the MAIN board.
2.
Set a disc. (YEDS-18)
3.
Press the
u
button.
4.
Check the oscilloscope waveform is as shown below.
A good eye pattern means that the diamond shape (
◊
) in the
center of the waveform can be clearly distinguished.
RF Signal reference Waveform (Eye Pattern)
VOLT/DIV : 100 mV (With the 10:1 probe in use)
TIME/DIV : 500 ns
To watch the eye pattern, set the oscilloscope to AC range and
increase the vertical sensitivity of the oscilloscope for easy watch-
ing.
5.
Stop revolving of the disc motor by pressing the
x
button.
TJ403 (RF GND)
TJ401 (RF)
IC402
IC404
oscilloscope
(AC range)
+
–
MAIN board
TJ401 (RF)
TJ403 (RF GND)
RF level
0.45 to 0.70 Vp-p
www.freeservicemanuals.info
6/21/2017
Digitized in Heiloo Netherland
