3-8 SWEEPFREQUENCY
OPERATION Thesignal generator can generate broad (full range) and narrow band
sweeps across the frequency range of the instrument. The 681XXC has
four sweep frequency modes—analog sweep, step sweep, manual
sweep, and list sweep. Descriptions and operating instructions for the
analog, step, and manual sweep frequency modes begin on this page.
List sweep frequency mode descriptions and operating instructions be-
gin on page 3-41. Use the Analog Sweep, Step Sweep, Manual Sweep,
and List Sweep Frequency Mode menu maps (Chapter 4, Figures 4-3,
4-4, 4-5, and 4-6) to follow the menu sequences.
Analog Sweep
Mode In analog sweep frequency mode, the signal genera-
tor’s output frequency is swept between selected
start and stop frequencies. Sweep width can be set
from 1 MHz to the full frequency range of the signal
generator.Sweep time can be set for any time in the
range of 30 ms to 99 sec. The lower frequency limit
for analog sweeps is 10 MHz.
When the sweep width of the analog sweep is
>100 MHz, the sweep is phase-lock corrected at both
the start and stop frequencies and at each band-
switch point. When the sweep width is £100 MHz,
only the center frequency of the sweep is phase-lock
corrected.
Selecting
Analog Sweep
Mode
Toplace the 681XXC in analog sweep frequency
mode, press the main menu key
CW/SWEEP
SELECT
At the resulting menu display,press Analog . The
Analog Sweep Menu (below) is then displayed.
3-26 681XXC OM
LOCAL (FRONT SWEEP FREQUENCY
PANEL) OPERATION OPERATION