SONY PMCDR45L
Manual de Servicio

5-3. CD SECTION
Notes on Check 1. Perform the traverse check in the CD test mode. After check, be sure to exit the test mode. 2. Perform check in the order given. 3. Use the disc (YEDS-18, Parts No. 3-702-101-01) only when so indicated. Before check Put the set into test mode and perform the following checks. Repair if there are any problems. � Sled Motor Check Press >, . keys and confirm that the Optical pick-up moves smoothly from the innermost to outermost circumference and back smoothly and with no catching or abnormal noises. (Cancellation of BTL mute) > : Optical pick-up moves to the outer circumference. . : Optical pick-up moves to the inner circumference. � Focus Search Check 1. Press the CD u key. (Focus search operation is performed continuously.) 2. Look at the Optical pick-up objective lens and confirm that it moves up and down smoothly, with no catching or abnormal noises. 3. Press x button. Confirm that focus search operation stops. If it does not, press x button again longer. How to Enter the Set into Test Mode 1. Set the function switch to power off. 2. Set the function switch to CD while MODE key and > key pressing. The set is into CD test mode (88 is displayed). 3. Turn the power off to release test mode. How to Exit the Test Mode Turn the POWER OFF.

TRAVERSE Check This check is to be done when the optical pick-up block is replaced. Check Procedure: 1. Connect the oscilloscope to test point TP (VC) and TP (TE) on MAIN board. Insert disk (YEDS-18). 2. Put the set into test mode. 3. Optical pick-up setting to the center by > or . button pushing. 4. Press u button. 5. Check that the oscilloscope traverse waveform is symmetrical, as shown in the figure below. 6. Release test mode after adjustment is completed.
VOLT/DIV: 0.1 V TIME/DIV: 1 ms (with the 10:1 probe in use.) 1.2-1.8Vp-p

Focus Bias Check This check is to be done when the optical block replaced. Check Procedure: 1. Connect the oscilloscope to test point TP (VC) and TP (RF) on MAIN board. Insert disk (YEDS-18). 2. Put the set into test mode. 3. Optical pick-up setting to the center by + or � button pushing. 4. Press the u button and press the DISPLAY ENTER button. (Tracking servo ON) 5. Check 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. 6. Release test mode after adjustment is completed. � RF signal reference waveform (eye pattern)

VOLT/DIV : 50mV TIME/DIV : 500 ns (With the 10:1 probe in use) 1.1- 1.3 Vp-p

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

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