Force the CM5's Wi-Fi onto 5 GHz with nmcli
A CM5 that quietly joins the crowded 2.4 GHz band inside a metal case gets a steadier link once NetworkManager is told to use 5 GHz only.
What it takes
- Config change
Difficulty 1 of 3 — easy.
Details
blackperl337 found his CM5 associating at 2427 MHz with poor throughput. nmcli connection modify "<name>" 802-11-wireless.band a followed by nmcli connection up "<name>" moved it to 5180 MHz, and together with an external SMA antenna on a printed mount the link became noticeably better and more stable. snipeytje's reply argues the antenna did most of the work; bored99 adds that Ubuntu 22.04 users should also set wifi.powersave = 2 in NetworkManager's config to keep the 5 GHz link from dropping.
Links
Open at Forum threadRelated mods
One line in config.txt switches a CM4 from its on-module PCB antenna to the u.FL connector the uConsole's antenna is actually plugged into.
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