ℹ️ The article below from 2014 describes how to capture 802.11n packets using AirPcap Nx hardware ($699) For a more modern packet capture method, you can capture 5 GHz 802.11ac/ax packets automatically in Chanalyzer 6 using a supported Wi-Fi adapter.
Chanalyzer is free to use when opening .pcap files - check out samples here.
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In some cases, you may want to perform packet captures for Wireshark. One case might be when you want to perform a packet capture on channel 12 or 13.
Set up the Packet Capture
1. Click View > Wireless Toolbar. The Wireless Toolbar will appear just below the Main toolbar.
2. Use the Wireless Toolbar to configure the desired channel and channel width.
3. Under Capture, click on AirPcap USB wireless capture adapter to select the capture interface.
Note: If the AirPcap isn't listed, press F5 to refresh the list of available packet capture interfaces.
Note: The AirPcap has been discontinued by RiverBed and is 802.11n only.
4. Click the Start Capture button to begin the capture.
5. When you are finished capturing, click the Stop button.
Saving the Capture
1. To save the capture, click File > Save.
2. Name the file, and click Save.
Note: .Pcap and .Pcap-ng are good filetypes to use for the capture if you plan to use Eye P.A. or Chanalyzer 6 to open the capture.
3. Eye P.A. or Chanalyzer 6 can now open the capture file.