Draytek Vigor2860 Series User Manual page 317

For 5 GHz: At present, the router can connect to 11a Only,
11n Only(5 GHz), Mixed (11a+11n) stations
simultaneously. Simply choose Mixed (11a+11n) mode.
In which, 802.11b/g operates on 2.4G band, 802.11a
operates on 5G band, and 802.11n operates on either 2.4G
or 5G band.
Channel Means the channel of frequency of the wireless LAN. The
default channel is 6. You may switch channel if the selected
channel is under serious interference. If you have no idea of
choosing the frequency, please select Auto to let system
determine for you.
For 2.4GHz:
For 5 GHz:
Vigor2860 Series User's Guide
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