Giga-tronics 2508A, Operation Manual

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2500A Menus
2500A Series Operation Manual, 34172 Revision C, March 2008
The following explains each item in the Ramp Freq Center/Span menu:
Center Frequency. This menu item displays and allows you to modify the ramp start frequency. This is
the frequency that will be used as the starting frequency of the frequency sweep. Note that the start fre-
quency must be less than the stop frequency. If the start frequency is set higher than the stop frequency,
the stop frequency is automatically adjusted to the same value.
Span Frequency. This menu item displays and allows you to modify the ramp span frequency. The span
determines the range of the frequency weep beginning at half the value of the span setting lower than the
center frequency and ending at a frequency one half the value of the span setting higher than the center
frequency.
Power. This menu item displays and allows you to modify the output power level to be used during the
center/span frequency sweep. The range of the power level can be set to any valid power setting of the
instrument.
Sweep Time. This menu item allows you to view and modify the sweep time. This is the amount of time
that elapses for one cycle of a frequency sweep to complete.
Resolution. This menu item allows you to view and modify the sweep step resolution. The sweep step
resolution can be set to 401, 801 and 1601 frequency steps.
Ramp Power Menu. Pressing this softkey invokes the Ramp Power menu in the display. See “Ramp
Power Menu”, below, for Ramp Power menu item descriptions.
2.3.3.3 Ramp Power Menu
The Ramp Power menu allows you to view and modify settings related to the instrument’s power sweep-
ing feature. When this feature is used, the power level of the RF output sweeps linearly from a predeter-
mined start power level to a predetermined stop power level in a predetermined amount of time, then
repeats. The power level can sweep from a lower to a higher power level, or vice versa. The output fre-
quency is held at the same value during a power sweep. The maximum settable range for ramp power
sweep is 45 dB.
NOTE:
As soon as the Ramp Power menu is chosen, the instrument calculates the ramp, then begins
sweeping the output power. The ramp is recalculated whenever a parameter is changed. Dur-
ing calculations, the following message is shown at the bottom of the display:
Preparing sweeping data...
When the calculations are complete and the output is actively sweeping, the following mes-
sage is shown:
Ramp sweeping
Figure 2-9 shows the Ramp Power menu: