Daewoo DSD-9255E, Service Manual

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CIRCUIT OPERATION MANUAL
2) Loop Through
Supports Loop Through for the Interface function of other Satellite Devices. That means, in other Satellite device, the
control of LNB related voltage and Tone are possible.
If the signal of AUX/IRD Control is in High status, the LNB voltage is provided from LNBP. If it s in Low, the power
can be supported from the external device in the Default states.
Sti5518 has internal Digital Encoder of PAL/NTSC.
Digital Encoder can modify the Digital Video Stream with the ration of 4:2:2 or 4:4:4, OSD, Sub-picture and produce
Analogue Base band PAL/NTSC signal and RGB signal.
Encoder output supports Interlace mode or Non-interlace mode.
There are 6 Pins for the Analogue Video output. (CVBS, S-VHS(Y/C), RGB)
Moreover, it supports Teletext, closed-captions and CGMS.
Following picture shows the signal formats from the individual output.
1) CVBS Timing
2) Comparison of RGB signals.
RGB Signal Pulse
a
b
c1
c2
d
NTSC-M
5.38 s (even lines)
5.52 s (odd lines)
1.56 s
8.8 s
9.3 s
9 cycles of 3.58MHz
PAL-BDGHI
5.54 s (A-type)
5.66 s (B-type)
1.28 s
9.3 s
10.1 s
10 cycles of
4.43MHz
PAL-N
5.54 s (A-type)
5.66 s (B-type)
1.28 s
9.3 s
10.1 s
9 cycles of
3.58MHz
PAL-M
5.73 s (A-type)
5.87 s (B-type)
1.28 s
9.3 s
10.1 s
9 cycles of
3.58MHz
Horizontal blanking Interval
d
b
a
0
H
c1 (bit aline = 0)
c2 (bit aline = 1)
Active video
Full digital line encoding
(720 pixels - 1440 T)
Analog line encoding
(710 pixels - 1420 T)
R B G
100
0
CVBS Timing
5. A/V Interface
(1) Video