SAF Spectrum Compact, Step-By-Step Manual

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equal to the centre frequency set on the transmitter (in MHz). Tap ENTER,
then HOME.
9. Tap SPAN, then MIN SPAN. Tap HOME.
Note : for wider radio channel bandwidths (80 MHz and up), tap SPAN and using
the keypad select a wider span e.g. 120. Tap ENTER. Tap HOME.
10. Tap TRACE MODE, then MAX HOLD. Tap HOME.
11. Start with the horizontal adjustments.
12. Loosen up the antenna to do the adjustments.
13. By slowly turning the antenna, sweep all the way through.
In addition to a prominent main lobe, antenna radiation patterns also have
smaller side lobes. The most common mistake during alignment is aligning to
a side lobe. Thus, it is important to sweep all the way through before fixing the
antenna position.
14. Now sweep the range once more, while simultaneously comparing the
two traces shown on the screen of Spectrum Compact.
15. Fix the position on the Spectrum Compact site when the NORMAL trace
more or less matches the blue MAXHOLD trace i.e. when the currently
received signal level is the highest possible.
16. Align the reference antenna vertically in the same manner.
17. Tap POWER IN BAND, then BW and using the keypad select the bandwidth
equal to the channel width set on the radio. Tap ENTER. Tap SET TO
CENTRE. Tap HOME.
18. Tap SWEEP CONT (if the button is grey).
If the calculated target received signal strength is below -80 dBm, zoom in on
the power axis for better visualization: tap TOOLS, tap LEVEL, then MAX and