KNS Ku-BAND RX, Инструкция по установке и эксплуатации

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drawback would be that the antenna will return to search when the
external device is disconnected or the external carrier is down, which
may be problematic during troubleshooting.
Medium
RSSD Threshold: Sometimes, the user transmits a CW carrier
with a very high C/N or the satellite may have very strong beacon
carrier with a unique frequency. (Caution: Please make sure that the
adjacent satellite is not using the same frequency for the beacon
signal !!! ). These carriers can be used for the purpose of searching
and tracking sources. In such cases, the RSSD tuner is
recommended because it has a very narrow BW of about 100KHz.
However, the RSSD must be used with a PLL-LNB with a high
stability option.
DVB C/N Threshold: We recommend the DVB C/N threshold
instead of the RSSD threshold when the antenna has no RSSD tuner
or if the RSSD tuner is broken. The DVB tuner can correctly detect
the desired carrier better than the DVB AGC threshold because the
noise level increases with the energy level when there is interference
from an adjacent satellite.
Note, with the threshold option, reference searching is the
recommended Sat. Finding method because it increases the
targeting accuracy.
Medium-low DVB AGC Threshold: The DVB tuner can only detect the energy
level, like RSSD. However, the valid detection range of BW is within
2MHz.
Low EXT. AGC Threshold: This option is not recommended if the
response time of the external device is slow. As such, it would not
be advisable to use it with the iDirect modem due to its slow
response time.
Table 6-1 Preference of searching reference
One of the most important facts when considering the tracking reference is how well the
tracking reference can resist interference from an adjacent satellite or a local
radar/microwave, etc. For example, C/N ratio tracking is preferred to AGC level tracking.