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Centre and Span
The instrument also allows the start and stop frequency parameters to be entered in terms of centre
and span. Pressing either the
Start
or
Stop
soft-key while it is highlighted will switch the mode
from start/stop to centre/span. To return to start/stop mode press the highlighted
Centre
or
Span
soft-key.
With centre/span mode selected the Edit Box shows the parameter, the Parameters Box shows
CENTRE
and
SPAN
in place of
START
and
STOP
and the Graph Box changes to show the
parameter which is being edited.
The selected parameter may be changed in either of the ways detailed in General: Numeric
Editing.
Sweep Time
To set the sweep time press the
Time
soft-key. The time parameter will appear in the Edit Box
and the Graph Box will show that sweep time is being edited.
The sweep time may be changed in either of the ways detailed in General: Numeric Editing.
Frequency Marker
The sweep frequency marker may be set to any frequency within the sweep range or it may be
turned off. The sweep marker and the sweep sync form a composite signal which appears at the
SYNC OUT connector as
Sweep Sync
. This signal goes high at the start of sweep and then goes
low as the sweep goes through the marker frequency. If the marker is off the
Sweep Sync
signal
goes low at the mid point of the sweep.
To set the frequency marker press the
Marker
soft-key. The marker parameter will appear in the
Edit Box and the Graph Box will show that sweep marker is being edited.
