Digital Tv: Measuring The Power Of Digital Channels - Promax TV EXPLORER HD+ Manual De Instrucciones

USER'S MANUAL. TV EXPLORER HD+
When measuring channels in the satellite band or digital channels, to measure the
C/N ratio correctly, the bandwidth of the channel must be defined previously, using the
Channel BW option on the Measurements Configuration menu that appears when
pressing the [17] key.
In order to measure digital channel C/N ratio it is indispensable to tune channel at
its central frequency.
In the case of the presence of adjacent digital channels, these could mask the noise
level measurement.

5.14.6 Digital TV: Measuring the Power of Digital Channels

The extrapolated approach makes an approximation to a specific power value
according to some known power values, so that it measures channel power in the
bandwidth of the measuring filter and estimates the total channel power assuming that
the spectrum density is uniform over the entire bandwidth of the channel. The integrated
approach gives the true RMS value for any signal.
On selecting the CHANNEL POWER measurement mode, the screen displays the
following information:
In addition to the power of the digital channel (77.4 dBμV in previous figure) this
also shows the tuning frequency or channel, depending on the tuning mode selected,
and the offset frequency to calculate the digital channel power and the deviation
frequency of the central tuning calculated by the demodulator, measurement that
indicates the adjustment in the channel tuning.
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Figure 29.- Digital channel power measurement.
IMPORTANT REMARK
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