cxa1700aq Sony Electronics, cxa1700aq Datasheet - Page 44

• Manufacturer Part Number: cxa1700aq
• Description: Luminance And Color Signal Processing For 8mm Vcr
• Manufacturer: Sony Electronics

10. PB C cross talk cancellation
The playback C signal which passes through the BPF is input after frequency conversion. The feedback
chroma comb filter is configured as shown above.
By switching mode FBCL1 and FBCL2, the feedback loop gain from the Y comb is changed as shown
below.
When the feedback loop gain is increased the S/N ratio can be improved, but note that color smear in the
vertical direction and transient response get worse.
227ƒ
Playback Y
H
ACK • BF
Feedback loop
gain is large
Playback C signal
+
23
+
DL IN1
+
–
228ƒ
+
During editing
H
C comb
CCD
NOCORRE + EDIT + BF
–
+
+
ATT
HPF
—44—
CLAMP1
Y comb
LPF
ƒ
FBCL1
FBCL2
VCA1
EQ
Feedback loop gain
FBCL2
21
DL OUT1
High
Low
FBCL1
OUT
6.7dB
1.9dB
High
CXA1700AQ/AR
4.8dB
Low
0dB