Agilent Technologies E8247C PSG CW - Manual (Page 70)

60 Chapter 3
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.
To Level with Detectors and Couplers/Splitters
Figure 3-2 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 3-2 .
Figure 3-2 External Detector Leveling with a Directional Coupler