Configure External Leveling - Agilent Technologies X Series User Manual

Optimizing Performance
Using External Leveling (N5173B/83B Only)
feedback for the detection circuit has been moved beyond the output attenuator. Because the
attenuator no longer affects the amplitude of the output signal, the output amplitude is determined
by only the Set ALC Level softkey.
With external leveling selected, the signal generator enables attenuator hold and the power range
approximates the range of a standard option (no attenuator) signal generator (see the Data Sheet).
As stated earlier, the actual output power may vary due to the external detector and the
coupler/power splitter performance characteristics.
NOTE
When the internal detector (Internal selection) is reselected, the signal generator does not
turn the attenuator hold off.
Even though the output attenuator no longer affects the output power, it is still useful to drive the
ALC circuit to its mid–power point of approximately 0 dBm, which is optimal for the internal leveling
circuitry and typically provides the best amplitude flatness results. This is useful with power values
of −5 dBm or less. For example, to drive the ALC to approximately mid–power with a −20 dBm
power setting, add 25 dB of attenuation. This sets the ALC circuit to 5 dBm (−20 + 25).
NOTE
If there is too much attenuation, it will drive the ALC circuit too high and cause the signal
generator to go unleveled. Ensure that you decrease the attenuation as you increase the
power level.

Configure External Leveling

Basic Setup Process
• If working with a single frequency signal, perform Steps 1 through 5.
• If working with multiple frequencies:
a. Perform Steps 1 through 4.
b. Perform a user flatness correction, see
• If working with a sweep:
a. Perform Steps 1 through 4.
b. Setup the sweep, see
1. Setup the equipment, see
2. Configure the carrier signal, see
3. Select external leveling, see
4. Determine the output amplitude range, see
on page 115
5. Set the displayed power value, see
page 117
Equipment Setup
Set up the equipment as shown in
coupler/power splitter) as close as possible to the DUT.
114
"Using Flatness Correction" on page
"Configuring a Swept Output" on page
"Equipment Setup" on page 114
"Configuring the Carrier" on page 115
"Selecting External Leveling" on page
"Determining the Signal Generator's Amplitude Range"
"Adjusting the Signal Generator Display's Amplitude Value" on
Figure 5- 21 on page
50.
115.
115. Place the external detector (detector and
Agilent X-Series Signal Generators User's Guide
97.