12
Digital Mode (Satellite)
This shows a typical constellation from a DVB-S QPSK signal. The frequency and offset
are shown below the constellation diagram and the measured symbol rate is shown
below the frequency. The two thermometer bars show the BER and SNR of the signal.
The SNR thermometer increases from right to left and the BER thermometer gets smaller
from right to left, so that the best signal is shown by a longer white bar.
The lock time is shown at the top right and below this, the signal modulation and FEC.
The MER (Modulation Error Ratio) and the Output Bit Rate for the total transport stream
is also show.
When the NIT information is available, the NIT name and NIT Orbital Position appear.
Reading the SDT data shows the number of “Free to Air” channels.
A running count of the CB (Corrected Bit) and UCB (Uncorrected Block) errors is shown
as long as the signal is locked.