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.
Read moreWhat is the best channel for 2.4 GHz?
The recommended channels to use on 2.4 Ghz are Channel 1, 6 & 11 . As can be seen in the above diagram, these channels do not overlap into each other. In general 2.4 Ghz should be considered a legacy band for older devices that do not support 5 Ghz. It is often more crowded and less performant than 5 Ghz.
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