Digital Tv: Measuring Mer - Promax TV EXPLORER II Manual De Instrucciones

USER'S MANUAL. TV EXPLORER II/II+
Finally it is shown a status line with information about the detected signal. The
possible messages that can appear and its meaning are shown in the following list. The
messages are exposed from less to more fulfilment of the MPEG-2 standard:
No signal received
Any signal has been detected.
Signal received
A signal is detected but it can not be decoded.
Carrier recovered
A digital carrier has been detected but it can not be decoded.
Viterbi synchronized
A digital carrier has been detected and the Viterbi algorithm is synchronized, but
too many frames arrive with non correctable errors. It is not possible to quantify the
BER.
MPEG-2 TS DVB-S
Correct detection of a MPEG-2 signal.

5.14.8 Digital TV: Measuring MER

Once determined the suitable parameters for COFDM, QAM, QPSK or 8PSK
signal reception, it will be possible to measure MER, press
the MER measurement screen.
0
FREQ:
CH:
MPEG-2 TS DVB-T
Figure 39.- DVB-T/H (COFDM) signals MER measurement screen.
First of all, you will see the modulation error ratio measurement: MER.
Following, it appears the Noise Margin (NM) measurement (in the figure value 8.4
dB). It indicates a safety available margin according to the MER level measured that
allows signal degradation until arriving to the QEF (Quasi-Error-Free) limit value.
12/2013
NM:
10 20 30
650.00 MHz C/N: >21.3
-3 kHz POWER:
43 » MER:
CBER:
VBER:
[12] key until it appears
8.4 dB
40
dB
55.8 dBµV
19.5 dB
5.0E-2
5.3E-4
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