Hyundai HSS-730, Service Manual

Page: 10 / 56

HSS-730/830 & UFD505/515 SERVICE MANUAL HDT DVB SATELLITE STB
Page 10
3.3.1.3. Electrical Specification of Digital Tuner
Impedance
75
Ω
Return Loss > 8dB
Frequency Range 950 to 2150 MHz
Signal Level -65 to -25 dBm
AFC Range + - 3MHz
Connector IEC 169-24 female (F-type) and male (for loop-through)
Phase Noise
10 kHz
100 kHz
< -70 dBc/Hz
< -90 dBc/Hz
Synthesizer Step Size PSK & BPSK (Compliant to DVB-S)
Nyquist Shaping Filter 35% square root raised cosine
Symbol Rate 2 up to 45 Msps
Inner Code Convolitional (K=7)
FEC Code Rate 1/2,2/3,3/4,5/6,7/8. Automatically detected
Interleaving Factor I = 12
Outer code RS (204,188,T = 8)
Spectral Inversion Automatically detected
3.3.2. LNB Control
The LNB is powered through the center conductor of the RF coaxial cable connecting the LNB to
the STB. The polarization is switched by varying the power supply voltage of the LNB. In addition,
a 22kHz tone is used to switch the LNB between the low frequency band and the high frequency
band. The high frequency band is selected when the 22kHz is present.
The horizontal and vertical polarizations have different voltage ranges as shown in the below table.
Current 500mA max. (Short circuit protected)
Vertical Polarization Voltage 13 to 14.5 V
Horizontal Polarization Voltage 17 to 19 V
Software Controlled LNB ON/OFF Supported
The characteristics of the 22kHz tone is as follows:
Duty Cycle
50%
±
10%
Frequency
22 kHz
±
4 kHz
Amplitude
0.6V (
±
0.2V)
Rising and Falling Time
10
µ
s
±
5
µ
s
Software Controlled Tone ON/OFF Supported