Using External Leveling; Leveling With Detectors And Couplers/Splitters - Agilent Technologies E8241A User Manual

Optimizing Performance

Using External Leveling

Using External Leveling
The PSG signal generator can be externally leveled by connecting an external sensor at the
point where leveled RF output power is desired. This sensor detects changes in RF output
power and returns a compensating voltage to the signal generator's ALC input. The ALC
circuitry raises or lowers (levels) the RF output power based on the voltage received from the
external sensor, ensuring constant power at the point of detection.
There are two types of external leveling available on the PSG. You can use external leveling
with a detector and coupler/power splitter setup, or a millimeter-wave source module.

Leveling with Detectors and Couplers/Splitters

Figure 3-1 illustrates a typical external leveling setup. The power level feedback to the ALC
circuitry is taken from the external negative detector, rather than the internal signal
generator detector. This feedback voltage controls the ALC system, leveling the RF output
power at the point of detection.
To use detectors and couplers/splitters for external leveling at an RF output frequency of
10 GHz and an amplitude of 0 dBm, follow the instructions in this section.
Required Equipment
• Agilent 8474E negative detector
• Agilent 87301D directional coupler
• cables and adapters, as required
Connect the Equipment
Set up the equipment as shown in Figure 3-1.
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