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CIRCUIT DESCRIPTION
(3) 3-line Y/C separation (for PAL, 4.43 NTSC)
The video signal, input in Q5036, is processed for band limitation at FL5003, and its level is corrected at the
amplifier (Q5004, Q5005) at the successive stage. The signal from Q5006 is input to IC5007 at 1.5Vp-p.
IC5007 performs 3-line Y/C separation, and the Y signal from Pin 25 and the C signal from Pin 23 are output.
The Y and C signals are processed for band limitation at FL5001/ FL5002. They are amplified by two times at
the next stage, and then input in the changeover circuit of IC5005 and IC5006.
VIDEO
IN
Band limitation /
F chara cteristic correction
Q5036, FL5003
Q5004~Q5006
The output from IC5005 (Signal Y) is processed for F-characteristic correction and peaking at Q5011, Q5037,
Q5038, and Q5039 at the next stage. The resultant output is entered in IC5008 (PAL/NTSC demodulation
processing).
The output from IC5006 (Signal C) is entered in IC5008 (PAL/NTSC demodulation processing) and IC5010
(SECAM demodulation).
(4) SECAM system reception
During reception at the SECAM system, the video signal input is applied to Pin 15 of IC5008 through IC5006
and IC5005. Since a trap circuit is contained in IC5008, the Y signal is taken out. The video signal input is also
applied to Pin 24 of IC5010 and the C signal is taken out from the built-in bell filter. Since then, color signal
demodulation is performed at IC5010.
2. Demodulator circuit
(1) PAL/NTSC demodulation
After passing through the built-in delay line of IC5008, the Y signal is once output from Pin 4. This signal is
applied to Pin 15 of IC5012 (CTI) and amplified by two times there. The resultant output is generated at Pin 2.
In the NTSC mode, this signal directly passes through IC5017 (switching circuit) and returns to IC5008. Any
signal other than that once passes through the delay line DL5001 and then IC5017 (switching circuit), and
returns to IC5008. In IC5008, the signal is processed for pedestal clamp processing, black expansion process-
ing, DC reproduction, sharpness control, etc., and led to the internal RGB matrix circuit.
6-6
Three-line
Y/C separation
IC5007 (TC9090)
Band limitation /X2AMP
Q5007, Q5046, IC5015
Signal Y output
Band limitation /X2AMP
Q5009, Q5047, FL9002
Signal C output
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