Mikrotik Wireless Channel
In order to change the wireless channel (and thereforethe frequency) on Mikrotik, you must use the “center” channel:
This is especially true for Mikrotik routers using AC Wave 2 as it performs channel “bonding”. You also need to take into account your channel width. If you are using a 20mhz or 40mhz channel width.
Center Frequency
Lets use the center frequency of wireless channel 5 which is 2432 in this example.
On your Mikrotik you can enter 2432 and it will not throw an error (entering e.g. 2431 will throw an error)
Running a frequency scanner (such as WiFi Man on your phone) you will see that with these settings channels 3 to 11 will be occupied by your wireless network.
But why channel 3 to 11? Why not 3 to 7?
Because my channel width is set to 40mhz, it will use 2 channels below the center channel and 2 channels above the center channel, which should only occupy channel 3 to 7, with channel 5 as the center.
But if you look closely at your config, you might see something like this. Look at the Ce in the below screenshot.
Ce means it is an extention channel, and extention channels will use an additional 40mhz above or below your upper channel, and in some cases up to 80mhz beyond your upper channel as is the case with 802.11n and 802.11ac.
Hence, we are using channel 5 as our center channel, but our Wireless network will occupy from channel 3 up to channel 7, plus an additional 4 channels (80mhz) beyond our upper channel (because of Ce)
