Mid-tech RX 400p, Руководство пользователя

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RX 400p
98-05044 2-4
R1
The CDA-2B Antenna is designed with sufficient gain at low elevation angles to
perform well at higher latitudes where the signal power is lower and the satellite
appears lower on the horizon.
The BER number indicates the number of unsuccessfully decoded symbols in a
moving window of 2048 symbols. Due to the use of forward error correction
algorithms, one symbol is composed of two bits.
The bit error rate has a default, no-lock value of 500. As the receiver begins to
successfully acquire the signal, it will result in a lower bit error rate. For best
operation, this value should be less than 150 and ideally less than 20.
Section 4.11.1 provides more information on this feature. A graphical presentation of
the reception quality is provided in the signal tracking bar chart. Refer to Section 4.7
for further information.
2.4 Beacon Operation
The following sections describe the general operation and performance monitoring of
the beacon engine within the RX 400p.
2.4.1 Tune Modes
The RX 400p may be operated in either Automatic or Manual Beacon tune modes.
In Automatic Beacon Search (ABS) mode, the receiver will identify and tune to the
station providing the strongest DGPS signal. In Manual Tune mode, you specify the
frequency to which the receiver will tune, or select the desired beacon by name from
the built-in global listing.
Refer to Figure 5-12 and Section 4.16.5.3 to switch between Automatic and Manual
Tune modes using the display and keypad.
2.4.1.1 Automatic Beacon Search (ABS) Mode
When operating using the internal beacon sensor as the source of DGPS correction
information, the RX 400p operates in Automatic Beacon Search (ABS) mode by