Solution
Whenever a user tries to generate or acquire an RF signal using NI's RF drivers RFmx, NI-RFSG, and NI-RFSA, several settings are configured by the driver automatically.
However, it is impossible for the driver to know how the external LO is connected to the front panel of the instrument. Therefore, the driver uses the default value for this setting, even though it might not be correct. When using an external LO, the user must manually set the external LO configuration using the soft front panel.
In order to configure the External LO, follow the next steps:
- Open the RFmx Waveform Creator for WLAN.
- Select the Hardware Settings tab and click the Configure LO button:
- The software will open a pop-up window. Click the Master LO Source drop-down menu and click on the External LO option.
- Check the Control External LO Device(s) box.
- Then, click on the Ext LO Resource drop-down menu, and select your External LO, locating it by its name.
- Now, Click the Specify Connection button. A new pop-up window will appear.
- Click the generator you are using. In the following image, it is the "PXI1Slot5" Generator. Once you select it, keep the left-click of the mouse pressed, and move the object around. Place it on top of your external LO. In the next image that's the "PXI2Slot7". It should look like this:
- Repeat the steps for the analyzer. It should look like this:
- Click the Close button and close the previous pop-up window.
With these steps, the external LO should be configured properly, and the signal should be generated in center frequencies above 6.85 GHz.