Read Harman Kardon FL 8370 (serv.man4) Service Manual online
FL8370
1.5 Mirror Circuit
IRF signal is amplified by the mirror amp, and the peak and bottom component of amplified signal are
detected by peak and bottom hold circuit. The peak hold circuit covers traverse signal of up to 100KHz
component and bottom hold circuit capable of covering the envelope frequency of disc rotation. The time
constant for the mirror hold must be sufficiently larger than that of the traverse signal.
detected by peak and bottom hold circuit. The peak hold circuit covers traverse signal of up to 100KHz
component and bottom hold circuit capable of covering the envelope frequency of disc rotation. The time
constant for the mirror hold must be sufficiently larger than that of the traverse signal.
Figure 8. Mirror Circuit
1.6 EFM Comparator
The EFM comparator converts a RF signal into a binary signal.
Beacuse the asymmetry generated due to variations in disc manufacturing can not be eliminated by the
AC coupling alone, this circuit uses to control reference voltage of EFM comparator for eliminating
asymmetry.
Beacuse the asymmetry generated due to variations in disc manufacturing can not be eliminated by the
AC coupling alone, this circuit uses to control reference voltage of EFM comparator for eliminating
asymmetry.
Figure 9. EFM Comparator & asymmetry circuit
75
-
+
1
IRF
Peak and
Bottom
Hold
Bottom
Hold
-
+
39
-
+
-
+
17K
38K
19K
2.5K
96K
17K
1.5K
MIRROR
MCP
77
1
RFI
39
-
+
ASY
EFM
-
+
-
+
40K
19K
100K
100K
20K
85K
13
Click on the first or last page to see other FL 8370 (serv.man4) service manuals if exist.