Agilent Technologies 8360B, Руководство пользователя, Страница: 37 / 496

Center
Frequency/Span
Operation
Cen ter frequency/span is another w a y of establishing sw ept
op eration. This is just a dieren t w a y of dening sw eep limits. As an
example of cen ter frequency/span op eration:
Press 4 CENTER 5 4 4 5 4 GHz 5.
Press 4
SP AN
5 4
1
5 4
GHz
5.
The sw ept signal generator is no w sw eeping from 3.5 to 4.5 GHz (to
view these gures, press either 4 ST ART 5 or 4 STOP 5, then 4 SP AN 5). The
data display area indicates the cen ter frequency as w ell as the span.
Notice that the green SWEEP LED is on.
While span is the active function, try the rotary knob and arrow
k eys. This symmetrical increase or decrease of the frequency span
ab out the cen ter frequency is one reason that cen ter frequency/span
sw ept op eration is used instead of start/stop frequency sw eep.
Another example illustrates the subtleties of cen ter frequency/span.
Press 4 CENTER 5 4 4 5 4 GHz 5.
Press 4 SP AN 5 4 8 5 4 GHz 5.
Notice that the cen ter frequency c hanged. This is b ecause the cen ter
frequency could not accommo date a span of 8 GHz without exceeding
the low er frequency limit of the sw ept signal generator's sp ecied
frequency range. If the low or high frequency range limits are
exceeded, the inactive (cen ter or span) function is reset. Exp erimen t
with the rotary knob and the arrow k eys as alternate metho ds of
data en try .
1-8 Getting Started Basic