Nautel NV30LT-N, Руководство по эксплуатации и техническому обслуживанию

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NV30LT-N OPERATIONS & MAINTENANCE MANUAL OPERATING THE TRANSMITTER
VERSION 0.1 2015-03-01 PAGE 3.2.37
Use the left and right buttons to make fine adjustments.
Use the maximize or minimize buttons as required.
Use the “peak” button to place the cursor on the next successive peak (moving left to right) in the
spectrum.
Use the “cog” button to gain access to spectrum settings (see Figure 3.2.24 ) such as:
 Resolution Bandwidth: determines the FFT bin size or the smallest frequency that can be
resolved. Allowable range is 75 - 10,000 Hz. Default setting is 1000 Hz.
 Span : determines the start and stop frequencies of the analyzer with the carrier frequency always
at the center. Allowable range is 10 - 1200 kHz. Default setting is 1000 kHz.
 Averages : determines the number of averages that the analyzer performs per sweep. Press the
Clear Averaging button to restart the averaging process. Allowable range is 0 - 100 kHz. Default
setting is 19.
 Measurement Source : determines the source of the spectrum plot (transmitter output, audio
analyzer, etc.) that is being displayed. Selecting TX Output uses the exciter’s RF sample feedback
signal to display the RF output spectrum. Selecting Internal (Post EQ) displays the signal that will
be produced by the exciter. Selecting Internal (FM) uses the exciter’s RF signal, before being
equalized (if applicable). FM spectrum analyzer bandwidth is defaulted to 1 MHz, but can be
increased to 1.2 MHz. Selecting MPX bandwidth displays the entire composite baseband signal
(100 kHz wide).
Figure 3.2.24: Spectrum Settings
NOTE
: If you are using exciter A (controller) only, the FM spectrum analyzer displays the ideal spectrum
generated by the DSP. It is not necessarily the same as the spectrum seen at the RF output. If you are
using the optional exciter B (exciter), the spectrum analyzer can display the actual RF output sample.