Specifications
CONSTRUCTION
put (
AV
in) facility in their
TV
, can make
use of a pre-assembled audio-video to
RF
converter (modulator) module of 48.25MHz
or 55.25 MHz (channel 2 or channel3),
which is easily available in the market
(refer Fig. 4). The audio and video signals
from the decoder card are suitably modu-
lated and combined at the fixed
TV
channel’s frequency in the
RF
modulator.
The output from the modulator can be con-
nected to antenna connector of a colour
television.
Power supply unit: The
VCD
decoder
card and the
RF
modulator requires +5V and
+12V regulated power supply
respec-
tively. Sup-
ply design
uses two lin-
ear regula-
tors
7805 and
7812 (Fig. 5).
The voltage
regulators
fitted with
TO
220-type
heat sink
should be
mounted on
the
CD
player
enclosure’s
rear panel The circuit
can be wired on a gen-
eral-purpose
PCB
.
Installation
steps:
1. Find suitable
place in the enclosure
of the audio
CD
player
for fixing the decoder card,
RF
modulator,
and the power supply unit. Make appro-
priate diameter holes and fix them firmly.
2. Make holes of appropriate dimen-
sions on the rear panel for fixing sockets
for power supply and
RF
output.
3. Refer to Table II (Combined for Part-
I and II) and confirm
DSP
chip type of the
existing audio
CD
player for
EFM
(eight to
fourteenth modulation)/
RF
Signal (from op-
tical pick-up unit of the audio
CD
player)
pin number, connect
EFM
in wire to this
pin.
4. Make all the connections as per Fig.
6.
Text of articles on the above project
received separately from the two authors
have been been reproduced above so as to
make the information on the subject as
exhaustive as possible. We are further
TABLE II
DSP ICs and their EFM RF pin numbers
DSP IC EFM DSP IC EFM
/RF Pin /RF Pin
CXA 1372Q 32, 46
CXA 1471S 18, 27
CXA 1571S 18, 35
AN 8370S 12, 31
AN 8373S 9, 35
AN 8800SCE 12
AN 8802SEN 9
TDA 3308 3
LA 9200 35
LA 9200 NM 36
LA 9211 M 72
HA 1215 8 NT 46, 72
SAA 7210 3, 25
(40 pin)
SAA 7310 32
(44 pin)
SAA 7341 36, 38
SAA 7345 8
SAA 7378 15
TC 9200 AF 56
TC 9221 F 60
TC 9236 AF 51,56
TC 9284 53
YM 2201/FK 76
YM 3805 8
YM 7121 B 76
YM 7402 4, 71
HD 49215 71
HD 49233 19
AFS
UPD 6374 CU 23
UPD 6375 CU 46
M 50422 P 15
M 50427 FP 15, 17
M 504239 17
M 515679 4
M 51598 FP 20
MN 35510 43
M 65820 AF 17
M 50423 FP 17
CX 20109 20, 9
SAA7311 25
M50122P 15
M50123 FP 17
M50127 FP 17
UPD6374 CV 3
NM2210FK 76
YM2210FK 76
cuit, digital to analogue converter, micro
computer interface, video signal proces-
sor, and error detector, etc. Audio and
video signals stored on a
CD
are in a high-
density digital format. On replay, the digi-
tal information is read by a laser beam
and converted into analogue
signals.
One can also use another
VCD
decoder card comprising an
MPEG
IC
680, from Technics, and
a
DSP
IC
chip,
CXD
2500, with pow-
erful error-correction from
Sony. Similarly, another card,
KD
2000-680
RF
comprising an
MPEG
IC
chip,
CL
680 from Tech-
nics and a
DSP
IC
chip,
MN
6627
from C-cube.
RF modulator. For those
who do not have audio-video in-
KS 5950 5
KS 5990, 5991 5
KS 9210 B 5
KS 9211 B E, 9212 5
KS 9282 5, 66
KS 9283 66
KS 9284 66
CXD 1125 QX 5
CXD 1130 QZ 5
CXD 1135 5
CXD 1163 Q 5
CXD 1167 R 36
CXD 1167 Q/QE 5
CXD 20109 9, 20
CXD 2500 AQ/BQ 24
CXD 2505 AQ 24
CXD 2507 AQ 14
CXD 2508 AQ 36
CXD 2508 AR 36
CXD 2509 AQ 34
CXD 2515 Q 36, 38
CXD 2518 Q 36
LC 7850 K 7
LC 7860 N/K/E 7, 8
LC 7861 N 8
LC 7862 30
LC 78620 11
LC 78620 E 11
LC 7863 8
LC 7865 8
LC 7866 E 7, 8
LC 7867 E 8
LC 7868 E 8
LC 7868 K 8
LC 78681 8
MN 6617 74
MN 6222 11
MN 6625 S 41
MN 6626 3, 62
MN 6650 6
MN 66240 44
MN 66271 RA 44, 52
MN 662720 44
CXA 72S 18, 46
CXA 1081Q 2, 27
PARTS LIST-2
Semiconductors:
IC1 - LM78L05, voltage regulator +5V
IC2 - 78L12, voltage regulator +12V
D1,D2 - 1N4001, rectifier diode
Capacitors:
C1 - 2200µF, 35V electrolytic
C2,C3 - 100µF, 16V electrolytic
Miscellaneous:
- 230V AC primary to 18V-0-18V,
1A sec. transformer
- MPEG decoder card (C-cube Digital
Tech.)
- TV modulator (optional)
- AF plugs/jacks (with screened wire)
- Co-axial connectors, male/female
- Co-axial cable
The decoder card converts your
CD
play-
ers or video games to
VCD
player to give
almost
DVD
-quality pictures.
The decoder card mainly consists of
sync signal separator, noise rejection cir-
Fig. 4: Layout of TV RF modulator
Fig. 5: Power supply to cater for MPEG card and RF modulator
Fig. 6: Block diagram of connections to decoder card and codulator
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