Thank you! I will send a message to the developer. The measured power (about -60 dBm in 1m from the antenna) is much lower than obtained with the original firmware and the WiFi led does not light. But, anyway, the 5GHz support to this device is a good news, after so long time!
This is what I got:
-----------------------------------------------------
OpenWrt SNAPSHOT, r8629-f98fde2db4
-----------------------------------------------------
root@OpenWrt:~# cd /etc/config/
root@OpenWrt:/etc/config# cat wireless
config wifi-device 'radio0'
option type 'mac80211'
option hwmode '11g'
option path 'platform/10300000.wmac'
option legacy_rates '1'
option channel '1'
option htmode 'HT40'
option country 'US'
option txpower '30'
config wifi-iface 'default_radio0'
option device 'radio0'
option network 'lan'
option mode 'ap'
option ssid 'OpenWrt'
option encryption 'psk2'
option key 'xxxxxxxx'
config wifi-device 'radio1'
option type 'mac80211'
option hwmode '11a'
option path 'pci0000:00/0000:00:00.0/0000:01:00.0'
option htmode 'VHT80'
option country 'US'
option legacy_rates '1'
option channel '112'
config wifi-iface 'default_radio1'
option device 'radio1'
option network 'lan'
option mode 'ap'
option ssid 'OpenWrt5G'
option encryption 'psk2'
option key 'xxxxxxxxxx'
root@OpenWrt:/etc/config# iwinfo wlan1 info
wlan1 ESSID: "OpenWrt5G"
Access Point: 00:0C:43:26:60:xx
Mode: Master Channel: 112 (5.560 GHz)
Tx-Power: 23 dBm Link Quality: unknown/70
Signal: unknown Noise: unknown
Bit Rate: unknown
Encryption: WPA2 PSK (CCMP)
Type: nl80211 HW Mode(s): 802.11nac
Hardware: 14C3:7650 14C3:76xx [Generic MAC80211]
TX power offset: unknown
Frequency offset: unknown
Supports VAPs: yes PHY name: phy1