Digital Tv: Measuring The Power Of Digital Channels - Promax US TV EXPLORER 2 User Manual

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 US TV EXPLORER II measures digital channel power in the measurement
filter bandwidth and estimates total channel power assuming that spectral density is
uniform throughout channel bandwidth.
On selecting the CHANNEL POWER measurement mode, the screen displays
the following information:
10
FREQ:
CH:
MPEG-2
Figure 29.- Digital channel power measurement.
In addition to the power of the digital channel (55.8 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.
In order that the power measurement of a DVB-S/S2 digital channel will be good it
is essential to have previously defined the channel bandwidth using the Channel BW
option, in the Measurements Configuration menu that appears when pressing
[17] key.
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USER'S MANUAL. US TV EXPLORER II
30 50 70 90 110
57.00 MHz C/N: >21.3
-3 kHz » POWER: 55.8
A02 MER: 19.5
SER:
VBER:
IMPORTANT REMARK
130
dB
dBµV
dB
1.0E-5
1.0E-8
10/2007