Fluke AIRCHECK User Manual page 71

Channels that do not have access points can show
802.11 usage because of overlap from access points on
adjacent channels.
Non-802.11 bar graphs (gray) may not be available
in some countries.

By default, the tester shows channels on the 2.4 GHz
and 5 GHz bands. To see only one band, change the
setting in Tools > Manage 802.11 settings.
 
Press AP List to see the access points that use the
highlighted channel.

The channel that the tester currently monitors.
The color of the bars shows the status of the country
code for the regulatory domain. See "802.11d
Operation" on page 43.
Note

The number of access points that the tester
hears at your location. This shows the number of
physical access points if Group virtual access points is
selected. See page 38.
Up to 500 access points can be stored in the access point
database on the tester. When the access point icon turns
yellow, this indicates that greater than or equal to 400
access points have been discovered.
When the icon turns red, this indicates that 500 or more
access points have been discovered and the access point
database is full. Any new access points seen will not be
included in the list.

To see descriptions of the icons on the Channel Usage

screen, press Legend.
Channel Usage
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