Philips Semiconductors
Digital TV sound demodulator/decoder
Preliminary specification
TDA9874H
2.1.1 ANALOG 2-CARRIER SYSTEMS
Table 1 Frequency modulation
STANDARD
M
M
B/G
I
D/K
D/K
SOUND
SYSTEM
mono
A2+
A2
mono
A2
A2*
CARRIER
FREQUENCY
(MHz)
4.5
4.5/4.724
5.5/5.742
6.0
6.5/6.742
6.5/6.258
FM DEVIATION (kHz)
MODULATION
NOM. MAX. OVER. SC1
15
25
50 mono
15
25
50 1⁄2(L + R)
27
50
80 1⁄2(L + R)
27
50
80 mono
27
50
80 1⁄2(L + R)
27
50
80 1⁄2(L + R)
SC2
−
1⁄2(L − R)
R
−
R
R
BANDWIDTH/
DE-EMPHASIS
(kHz/µs)
15/75
15/75 (Korea)
15/50
15/50
15/50
15/50
Table 2 Identification for A2 systems
PARAMETER
Pilot frequency
Stereo identification frequency
Dual identification frequency
AM modulation depth
A2; A2*
54.6875 kHz = 3.5 × line frequency
117.5 Hz = l--i-n----e-----f-r-1-e---3-q--3-u---e----n---c---y-
274.1 Hz = l--i-n----e-----f-r--e-5---q7---u---e----n---c---y-
50%
A2+ (KOREA)
55.0699 kHz = 3.5 × line frequency
149.9 Hz = l--i-n----e-----f-r-1-e---0-q--5-u---e----n---c---y-
276.0 Hz = l--i-n----e-----f-r--e-5---q7---u---e----n---c---y-
50%
2.1.2 2-CARRIER SYSTEMS WITH NICAM
Table 3 NICAM
SC1
STANDARD
FREQUENCY
(MHz)
TYPE
MODULATION
INDEX (%)
DEVIATION
(kHz)
SC2
(MHz)
NICAM
DE-EMPHASIS
ROLL-OFF
(%)
NICAM
CODING
NOM. MAX. NOM. MAX.
B/G
5.5
I
6.0
D/K
6.5
L
6.5
FM
−
− 27 50 5.85 J17
FM
−
− 27 50 6.552 J17
FM
−
− 27 50 5.85 J17
AM
54 100 −
− 5.85 J17
40
note 1
100
note 1
40
tbf
40
note 1
Note
1. See “EBU specification” or equivalent specification.
1998 Apr 27
4