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Agilent E8663B Analog Signal Generator User’s Guide
Optimizing Performance
Adjusting Reference Oscillator Bandwidth
4.
Ensure that the file
FLATCAL1
is highlighted.
5.
Press
Load From Selected File
>
Confirm Load From File
.
This populates the user flatness correction array with the data contained in the file
FLATCAL1
.
The user flatness correction array title displays
User Flatness: FLATCAL1
.
6.
Press
Return
>
Flatness Off On
to On.
This applies the user flatness correction data contained in
FLATCAL1.
Returning the Signal Generator to GPIB Listener Mode
During the user flatness correction process, the power meter is slaved to the signal generator via
GPIB, and no other controllers are allowed on the GPIB interface. The signal generator operates in
GPIB talker mode, as a device controller for the power meter. In this operating mode, it cannot
receive SCPI commands via GPIB.
If the signal generator is to be interfaced to a remote controller after performing the user flatness
correction, its GPIB controller mode must be changed from GPIB talker to GPIB listener.
If an RF carrier has been previously configured, you must save the present instrument state before
returning the signal generator to GPIB listener mode.
1.
Save your instrument state to the instrument state register.
For instructions, see
“Saving an Instrument State” on page 34
2.
Press
Amplitude > More (1 of 2) > User Flatness > GPIB Listener Mode
.
This presets the signal generator and returns it to GPIB listener mode. The signal generator can
now receive remote commands executed by a remote controller connected to the GPIB interface.
3.
Recall your instrument state from the instrument state register.
For instructions, see
“Saving an Instrument State” on page 34
Adjusting Reference Oscillator Bandwidth
The reference oscillator bandwidth (sometimes referred to as loop bandwidth) is adjustable in fixed
steps for either an internal or external 10 MHz frequency reference. The reference oscillator
bandwidth can be set to 25, 55, 125, 300, or 650 Hz.
At frequency offsets below approximately 1 kHz, the stability and phase noise are determined by the
internal or external frequency reference. At frequency offsets above 1 kHz, stability and phase noise
are determined by the synthesizer hardware.
To optimize the overall phase noise performance of the signal generator for your particular
application, make this adjustment depending on your confidence in the stability and phase noise of
the external or internal reference versus the synthesizer hardware for various frequency offsets from
the carrier.
