Hi Sergio,
First, I set Edison to AP mode. My Edison AP name is michael-edison.
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root@michael-edison:~# iwconfig
wlan0 IEEE 802.11abgn Mode:Master Tx-Power=31 dBm
Retry long limit:7 RTS thr:off Fragment thr:off
Power Management:on
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Then I checked available AP list using WiFi Analyer application and found that it worked in 2.4GHz mode.
Best Regards,
Michael