Mid-tech RX 400p, User Manual

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RX 400p
4-57 98-05044
R1
floor, measured in decibels (dB). This value
effectively describes the reception quality, as a signal
is ‘louder’ if it is higher above the noise floor.
Interpretation of the SNR reading is discussed further
in Section 2.4.2.
MTP?100>?Q?25?
The menu item provides an indication of the amount
of successfully decoded differential data. Two figures
are provided – message throughput (MTP) and quality
(Q).
If reception is strong, all data will be decoded,
providing a 100% MTP. As reception becomes
weaker due to data errors caused by a weaker signal or
the introduction of radio frequency (RF) noise, the
MTP value will decrease. A 0% MTP reading
indicates that the beacon receiver is not successfully
demodulating any differential correction data.
The Q value indicates the number of consecutive 30
bit RTCM words received successfully, to a maximum
count of 25. The Q value changes rapidly, but the
menu is updated at 1 Hz. As such, its value may not
appear to update in an intuitive manner. Each RTCM
word is 30 bits in length. For a 200 bps modulation
rate, assuming a 100% MTP, approximately 7 words
will be decoded per second, resulting in quick changes
of Q.
Unselected?Bx
This menu item provides the name of the beacon to
which the receiver is tuned. This field will display the
beacon’s name only if it has been tuned by selecting it
from the receiver's internal Global Beacon Table. If
the receiver is in automatic mode or if it has been
tuned manually by frequency, ‘Unselected Bx’ will be
shown.