scan valid interval?

[movingincircles]

im in device manager, looking at my Atheros 5007EG wireless device properties, and theres a field for "scan valid interval" default setting at 60

when I double it, nothing happens...what is this setting?

 

[Crusty]

Scan Valid Interval?The amount of time (in seconds) before the client starts scanning for a better access point after reaching the roaming threshold or missing beacons. (See Table 1 for the threshold criteria.) The higher the value, the less time the client spends scanning for a better access point and the more time it has to send data.