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1. RF downlink frequency in Ku-band: If the searching and tracking reference is
configured for an RSSD or DVB carrier, then the operator must know the center
frequency of the RF down-link (receive) within the range of 10.95 ~ 12.75 GHz (Ku-
band RX frequency range).
2. LNB input frequency range: The LNB specifications sheet or manufacturer’s label on
the LNB usually identifies the input frequency range.
3. This value can also be calculated from the LNB LO frequency and the output
frequency range.
4. The BW of the carrier which the modem is receiving: Carrier size given in MHz.
5. The LNB stability: The specifications of the LNB usually include its stability.
First, the installer should determine whether:
1. The RF downlink frequency is within the 2 LNB input frequency. If not, the DVB or
RSSD tuner cannot be locked on the carrier.
2. If the searching reference is RSSD (narrow band tuner) or external lock, it is
important to use an LNB with +/- 10 KHz stability; typically, a DRO LNB has +/-500
KHz of stability, which can be problematic at best if the tracking carrier is a very
narrow carrier, as in a beacon and CW carrier. Also, the external modem can’t lock
on fast enough with the installed LNB with +/- 500 KHz of stability, which is also
problematic if the external lock is used for the searching method.
NOTE
: The SAMYUNG ENC antenna supports a universal LNB. The DC voltage selects
different LO frequencies to cover the entire Ku-band. However, most universal LNBs are
of the DRO type, where stability is +/- 500 KHz.
Summary of Contents for Ku-BAND RX
Page 1: ...INSTALLATION AND OPERATION MANUAL FOR VSAT VS61 Ku BAND TX RX ANTENNAS...
Page 15: ...7 Figure 3 1 Best Location Figure 3 2 Antenna Blockages...
Page 46: ...38 Figure 4 1 Step 1 of Reference Searching Definition...
Page 65: ...57 Figure 6 3 Co pol Kits Optional...
Page 120: ...d Appendix C Layout of Radome and Antenna Mounting Holes Figure C 1 Plastic Radome...
Page 121: ...e Figure C 2 FRP Radome Option...
Page 122: ...f...
Page 123: ...g Maritime Satellite Antenna...