Aaronia SPECTRAN HF-2025, Руководство пользователя

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There are TWO ways to manually set the frequency range:
- Center (Center frequency) and Span (Frequency range width)
or
-
fLow & fHigh (Start and stop frequency)
7.1 Center (Center frequency)
Chooses the frequency displayed in the middle of the readout. When changing
the
Center frequency , the SPAN parameter (see following description) is pre-
served. Thus, you can quickly evaluate different frequency ranges with identical
SPAN and without tedious re-adjustment of Start/Stop frequencies .
7.2 Span (Frequency range width)
Span adjusts the width of the sweep . Changes are relative to the aforementio-
ned “ Center frequency ” of the display. By changing Span , the Start/Stop fre-
quency (see following description) is automatically adjusted to be able to con-
form to the Span . Thus, the Span function can be compared to a “magnifying
glass”, though only operating in the X axis.
EXAMPLE: You chose 945MHz as the Center frequency . Now choose 10 as
Span , and the sweep will range from 940 to 950MHz. Choose 200 as Span , and
the sweep will be performed from 845 to 1.045 MHz, etc. In other words, you
always increase or decrease the resolution, centered around the
Center fre-
quency .
HINT: The right/left arrow keys can be used to directly move the sweep range
one SPAN unit to the right or left.
SPAN
Center Frequency
7.0 The main menu
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