Keysight EXG and MXG X-Series Signal Generators User’s Guide 119
Optimizing Performance for All Models
Using External Leveling (N5173B/83B Only)
Determining the Signal Generator’s Amplitude Range
The maximum output amplitude is frequency dependent. So if you are using multiple frequency
points and there is a need to know the maximum output amplitude for each frequency point, refer
to the “Amplitude” section of the X-Series Data Sheet. Then use this procedure to determine the
maximum amplitude for each band.
With external leveling and Option 1E1, the signal generator’s power range approximates that of a
standard option instrument (no Option 1E1). But Option 1E1 does let you use the attenuator to
drive the ALC to its mid–power point when using amplitude values less than 0 dBm. However
adding attenuation does decrease the upper range limit. For more information, see “Option 1E1
Output Attenuator Behavior and Use” on page 117.
1. If Option 1E1 is installed, adjust the attenuator to the desired level.
a. Press AMPTD > Atten/ALC Control > Atten Hold On > Set Atten.
b. Enter the attenuator value.
2. Turn on the RF output: Press RF On/Off to On
3. Set the AMPTD step increment value to one dB.
— Press AMPTD > Incr Set > 1 > dB.
4. Determine the minimum amplitude value:
a. Set the amplitude to -25 dBm.
b. Using the down arrow key, decrease the amplitude until the UNLEVEL annunciator appears.
c. Using the up arrow key, increase the amplitude until the UNLEVEL annunciator is gone.
The value showing when the UNLEVEL annunciator is gone is the minimum amplitude range
value.
5. Determine the maximum amplitude value:
a. Set the amplitude to a value that does not cause the signal generator to go unleveled.
b. Using the up arrow key, increase the amplitude until it goes unleveled or an error message
indicating that the upper limit has been reached shows at the bottom of the display.
c. Decrease the amplitude value:
— If the unleveled annunciator appeared, decrease the amplitude until the annunciator is
gone. The value where the annunciator disappears is the maximum upper range value.
— If the signal generator displays Error: 501, Attenuator hold setting over
range at the bottom of the display, the value showing is the maximum upper range
value.
If the Option 1E1 output attenuator value is too high (approximately
³ 55 dB), it will cause an unlevel condition to occur when the RF output is
turned on.