Agilent Technologies E8247C PSG CW - Manual (Page 79)

Chapter 3 69
Optimizing Performance
Creating and Applying User Flatness Correction
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 54 .
2. Press
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 54 .
Creating a User Flatness Correction Array with a mm-Wave Source Module
In this example, a user flatness correction array is created to provide flatness-corrected power at the output
of an Agilent 83554A millimeter-wave source module driven by an E8247C signal generator.
The flatness correction array contains 28 frequency correction pairs (amplitude correction values for
specified frequencies), from 26.5 to 40 GHz in 500 MHz intervals. This will result in 28 evenly spaced
flatness corrected frequencies between 26.5 GHz and 40 GHz at the output of the 83554A millimeter-wave
source module.
An Agilent E4416A/17A/18B/19B power meter (controlled by the signal generator via GPIB) and R8486A
power sensor are used to measure the RF output amplitude of the millimeter-wave source module at the
specified correction frequencies and transfer the results to the signal generator. The signal generator reads
the power level data from the power meter, calculates the correction values, and stores the correction pairs in
the user flatness correction array.
If you do not have the required Agilent power meter, or if your power meter does not have a GPIB interface,
you can enter correction values manually.