SONY CMT-NE5
Manual de Servicio

HCD-NE5 SECTION 4 TEST MODE
COLD RESET * The cold reset clears all data including preset data stored in the RAM to initial conditions. Execute this mode when returning the set to the customer. Procedure: 1. Press the I/1 button to turn the power on. 2. While pressing the x button, press the I/1 button and turn the [VOLUME] knob in the counter-clock wise. 3. The message �RESET� is displayed and the set is reset. PANEL TEST * All segments of liquid crystal display are tested, and the version and released date of the micro computer are displayed. Procedure: 1. Press the I/1 button to turn the power on. 2. While pressing the [DISPLAY] button, press the I/1 button and turn the [VOLUME] knob in the counter-clock wise. Then all segments of liquid crystal display are turned on. 3. Press the [DSGX] button, the version and released date of the micro computer are displayed. example of display:

SECTION 5 ELECTRICAL CHECK
Note: 1. CD Block is basically constructed to operate without adjustment. 2. Use YEDS-18 disc (3-702-101-01) unless otherwise indicated. 3. Use an oscilloscope with more than 10 M� impedance. 4. Clean the object lens by an applicator with neutral detergent when the signal level is low than specified value with the following checks. 5. Check the focus bias check when optical block is replaced. FOCUS BIAS CHECK
oscilloscope (DC range)

CD board TP (RFACO) TP (VC)
+ �

0116 V202
Version of micro computer (In this case, version 202) released date of micro computer (In this case, released of January 16)

Procedure : 1. Connect the oscilloscope to TP (RFACO) and TP (VC) on the CD board. 2. Insert the disc (YEDS-18). (Part No. : 3-702-101-01) 3. Press the [CD NX ] button. 4. Confirm that the oscilloscope waveform is as shown in the figure below. (eye pattern) 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: 0.2 V (with the 10: 1 probe in use.) TIME/DIV: 500 ns

4. Press the [BASS/TREBLE] button, the model name and distination are displayed. example of display:
1.1 0.2 Vp-p

NE5 NA
distination (In this case, North-American model) model name (In this case, HCD-NE5)

When observing the eye pattern, set the oscilloscope for AC range and raise vertical sensitivity.

Checking Location: � CD BOARD (Conductor Side) �

5. To exit from this mode, perform the �COLD RESET�. TUNER STEP CHANGE-OVER * Either the 9 kHz step or 10 kHz step can be selected for the AM channel step. Procedure: 1. Set the FUNCTION to AM, and press the I/1 button to turn the power off. 2. While depressing the [TUNING + M > ] button, press the I/1 button. 3. The message �9K STEP� or �10K STEP� is displayed on the liquid crystal display, and thus the channel step is changed over.

TP (VC)

TP (RFACO)

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