tween the 2 boards occur during low transi- tions.
4.Using pin 7 as the reference, monitor the clock signal on pin 6 of CN602. There are eleven negative clock pulses during 1 low cycle of the FSTBX signal.
5.Check the DSPSO signal on pin 5 of CN602. This is the serial information going to the front panel.
6.Check the DSPSI signal on pin 4 of CN602. This is the serial information coming from the front panel. Again, notice how it changes when a disc is playing.
7.If the signals are missing or improper, remove power from the player, and gently pull the flex cable out of CN602.
8.Measure the clock signal, the DSPSO signal, and the DSPSI signal using the FSTBX signal as a reference. All of the signals are present except the DSPSI signal.
Laser Checks
1.Check the DVD RF signal at TP502. The signal should look like a normal eye pattern with a peak to peak voltage of about 2.7 volts or higher. This peak to peak measurement varies from player to player and decreases as the laser ages.
2.Check the differential RF signals at pins 16 and 17 of CN501. They should be about 0.5
10
volts peak to peak.
3.Clean the objective lens with a cotton swab and alcohol if the signal is low.
4.Recheck the RF signal, and if it is still low replace the laser slide assembly.
5.Another way to check the power of the laser is with a laser power meter. A new laser should measure about 0.2 milliwatts.
6.You can also visually check the laser during power on. However, be sure not to look directly into the laser.
7.The RF signal for a CD is checked at TP501. It also looks like normal eye pattern, but its frequency is lower than that of the DVD. Normally it is about 1.6 volts peak to peak.
Focus and Tracking Checks
1.For a focus problem, check the focus error signal at TP504. Cycle the power off then on to see the operation of the focus error signal. Gently tap the side of the player to check the operation of the signal. If the signal is miss- ing or improper, the main board is most likely at fault.
2.Play a CD and check the focus error signal at TP504.
3.For a tracking problem, check the tracking error signal at TP507. Cycle the power off then on to see the operation of the tracking error signal. Gently tap the side of the player
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