Operations and Maintenance Manual

VS300 Operations and Maintenance Manual Operating the transmitter
Page 2-36 Issue 10.0 2019-01-18
Click the panel to display a cursor in the approximate area. The cursor position (frequency and
amplitude) is noted in the upper, right-hand corner of the panel. Click on other areas of this
instrument panel to provide a coarse adjustment of the cursor position.
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 2.23 on page 2-35) 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 fre-
quency 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 that is being dis-
played. 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 base-
band signal (100 kHz wide). For VS-HD systems, selecting Internal (Hybrid) displays
the signal that will be produced by the exciter and selecting
TX Output displays the sig-
nal at the transmitter’s RF output.
Figure 2.24: Spectrum Settings
FM only
Transmitter
VS-HD
Transmitter