Thresholds; Digital Measurements - Alcad 918 Serie Manuel D'utilisation

11.6 Thresholds

Predefined thresholds are used to assess if the measurement is pertinent.
Decision thresholds are used to display the measures « Power Level » and « Measurement Map »:
Measure:

11.7 Digital measurements

In digital measurement mode, in addition to the RF level and to the C/N hereabove, the appliance also
displays the various BER (Bit Error Rate), the PER (Packet Error Rate) and the MER (Modulation Error Ratio)
under DVB-T/H, DVB-T2, DVB-C, DVB-S, DVB-S2 or DSS.
You also get the LKM:x.xdB (Link Margin) specification.
This expression in dB is the difference between the measured MER and the limit MER before disconnection
of the image: it's the security available before disconnection.
The bargraphs are displayed with colors depending on the measured error rates:
-
-
-
An automatic frequency check (AFC) is automatically activated in error rate measurement
mode.
52
Standard
Analogical terrestrial TV
DVB-C
DVB-T/H, DVB-T2
FM, carrier
Analogical satellite TV
DVB-S, DSS
DVB-S2
min threshold
red display
GREEN: good error rates
ORANGE: BERo > 10 -4 (QEF : Quasi Error Free) without lost packet
RED: lost packets (PER).
Min Max
57 74
57 74
35 70
50 66
47 77
47 77
47 77
max threshold
green display orange display