Chapter 4 - Testing and Test Point Access
This section is divided into two parts: 1) Test point access; and 2) testing the RF and servo sections using the
service / test mode.
The signals are generated by the optical assembly's photo detectors as listed in Table 4-1.
Photo
Detector
A-D
E & F
G & H
Access - RF Output
The RF test point is easily accessed. See Figures 4-1 through 4-3. Figure 4-4 shows the RF waveforms.
Table 4-1 - Photo Detector and Their Manufactured Signals
Signals
TE (DVD only),
TE = DVD tracking error.
FE, PI, Mirror,
FE = Focus error.
RF
(eye
PI = "Pull In" is the analog sum of A-D detectors. Disc ID
pattern)
the disc and MIRR.
MIRR counts tracks and ID disc.
RF = Sum of A-D detectors.
TE + and TZC
CD tracking error, track counting
TE – and TZC
CD tracking error, track counting
R F m e a s u r e m e n t s l o c a t i o n s I
FIGURE 4-1 - IC201 RF TEST POINT
Purpose
1 R F i n / P I N 2
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4. Testing and Test Point Access