Even though SPECTRAN instruments already are impressively accurate consi-
dering their price,
in practice
an even higher measurement inaccuracy than the
one specified for the instrument has to be assumed. There are various reasons
for this, such as temperature dependance, reproducability and many others.
This has to be taken into account at every measurement.
8.8 The cursor and zoom features
In
spectrum analysis
mode, you can use the
Jog Dial
to
activate a cursor. This cursor allows you to determine the
exact frequency and signal strength at an arbitrary point
in the display. To activate the cursor, simply rotate the Jog
Dial and the cursor will appear as a thin line in the spec-
trum. To deactivate it, simply press the menu key twice.
The part of the display covered by the cursor gets drawn
in reverse colour, thereby preserving its information.
By rotating the Jog Dial, the cursor can be placed at any desired position on the
display. The readout on the large main display, the exposure limit display and
demodulation now EXCLUSIVELY represent the frequency at the current cursor
position! The current frequency and level display at the cursor position only get
updated
after
each sweep and are displayed in the first (leftmost) marker field.
Naturally, no auto marker functionality is available in this mode.
Once you have positioned the cursor, you can
zoom into
a signal by
pressing
the Jog Dial. This will set the CENTER frequency to the current cursor positi-
on/frequency, halve the SPAN and initiate a new sweep. In other words, you
zoom
into the signal by 50%. This procedure can be repeated as often as you
wish until the desired resolution has been reached. A very useful feature. But
please note that a zoom back out is not possible.
You can turn off the cursor by pressing the menu key twice.
ATTENTION:
The cursor should NOT be used in HOLD mode, as it will not be
erased (just like the rest of the display) and thus produce an entirely “black“ and
useless display very quickly!
Frequency
and
level
at the current cursor position
Cursor
Parts of the graphic covered by
the cursor are drawn inverted
8.0 Correct measurement
Firmware V 1.0 / © 2005-2013 by Aaronia AG, D-54597 Euscheid, www.aaronia.com
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