For best results, it is highly recommended to keep the 2.4 GHz channels to 1, 6, and 11, as these channel settings will allow for virtually no overlap in the WiFi signal.
Read moreWhich is better 20 MHz or 40 MHz?
Thus, the difference between 20 MHz and 40 MHz is throughput. 40 MHz has higher throughput than 20 MHz thanks to channel bonding. There are downsides to channel bonding. While 40 Mhz might have higher throughput than 20 Mhz, it also reduces the number of non-overlapping channels.
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