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Level of multipath
reception in percent. The
multipath
detector measures
amplitude fluctuations of the signal. An FM signal is broadcast with a fixed level. Therefore level
fluctuations indicate degraded signal quality. At
multipath
conditions large level fluctuations can
be measured. For best measurement accuracy try to find reception point with lowest
multipath
level.
Shows currently selected
IF filter bandwidth
.
Group 2. This group shows Stereo multiplex related parameters
These two bargraphs shows the
deviation
from
positive
and negative component of
MPX signal
. In wideband FM, used in wireless broadcasting, the
instantaneous frequency varies above and below the frequency of the carrier with no modulation.
When the instantaneous input wave has positive polarity, the carrier frequency shifts in one
direction; when the instantaneous input wave has negative polarity, the carrier frequency shifts in
the opposite direction. At every instant in time, the extent of carrier-frequency shift (the deviation)
is directly proportional to the extent to which the signal amplitude is positive or negative.
Mod Input
FM Output
Shows the deviation caused by
Pilot
tone injection. As good practice the
pilot deviation should be about 10% from total deviation of the RF carrier.
Same for RDS signal.
Shows the average program loudness measurements as defined by ITU
BS.1770-4 and EBU R128 recommendations. The following measurements are available:
Momentary
– average program loudness measured over a 0.4s sliding time window, not gated;
Short-term
– average program loudness measured over a 3s sliding time window, not gated;
Long-term
– average program loudness measured over a variable sliding time window, gated
as described in ITU BS.1770-4. The time window can be varied between 10s and 120s.
Содержание DB4005
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