GE MDS SD4 Series, Руководство для стартапов

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12 MDS SD4 Startup Guide 05-4669A01, Rev. A
The spectrum analyzer display is accessed by entering
spectrum xxx.xx
x.x
at the command prompt, where the
x
characters denote the center
frequency and span frequency , respectively. The frequencies are
entered in megahertz. For example, a sample entry would be
spectrum
410.00 1.5
, corresponding to a center operating frequency of 410.00
MHz and a span (sweep width) of 1.5 MHz.
A sample display with these parameters is shown in Figure 8 . The dis-
play creates a received signal strength indication (RSSI) vs. frequency
plot for the center frequency and all surrounding signals within the
span. By analyzing the display, you can determine the presence of
other signals near the transceiver’s operating frequency. Refer to the
SD4 Reference Manual for additional details.
Invisible place holder
Figure 8. Internal Spectrum Analyzer Display
COM1 CONNECTIONS
The
COM1
connector is used to connect a PC to the radio for manage-
ment or diagnostics. A straight-through cable is required that connects
Pin 2 (RXD), Pin 3 (TXD), and Pin 5–Ground. (See
Figure 9 .)