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
22
Summary of Contents for SPECTRAN HF-2025
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