Test points and references:
A: make sure static free work environment is observed at all times when working with Laser Pickup.
With the unit totally turned OFF, confirm the impedance of the Focus Coil and the tracking coil at CN501. Between
pin 10 and 13, 8.2ohm for Focus coil and across pin 11 and 12, 8.3ohm for the Tracking Coil.
Check and verify procedure as given on page 43,44 of service manual. For disk to be recognized while carousel is
rotating but fail to spin and focus is a result of missing LD ON. This happens when one of the connectors at any of
the three points (Fig1 A, B and or Fig2 C) is lacking good contact to the ribbon.
***The laser pick needs no adjustment!!! ***
The troubleshooting guide given between pages of 43 and 50 is extremely helpful to determine the condition of the
PICKUP.
B: Disregarded Step 3 of page 45 and make correction as follows.
The reference should be:
lop = Voltage between
E522 and E523 3.3ohm
The voltage drop across R505 (3.3ohm) resistor is higher than 218~238mvDC in normal operating condition and the
LD is not on, connection (Fig1 A, B and or Fig2 C) may be loose or poor. This indicates the LD is not present as
load to the voltage rail R505.
The Individual optical output level may be monitored at the pickup connector point using an oscilloscope with no
more than 10pf input capacitance.
For location refer to manual Page 50.
D: To help reduce the break up of the video signal, remount CORE
#230957. The installation of this core should be as illustrated on Fig14.
** Since the root cause for the failure of DV-C600 and DV-C601 is
mainly noisy pick-up signal do to poor connector terminals, it is very
important all of the necessary steps mentioned are exhausted before
attempting to replace the PICKUP.
If the shorting PCB seen in Fig 3 is not in place, you
will need to keep the DSP still connected to CN501
connector until pick-up shorting is done as seen on
figure 10. Keep DSP attached to the frame with an
electrical tape.
Fi
16
TP-515
