I just purchased an Alfa USB wifi network adapter with the MediaTek 7610U chipset and although it's a great USB adapter one of it's major selling points is supposed to be its power. But I can't even get it to the US standard of 100mW because OpenWrt will not allow me to set anything above 18dBm (63mW) in wireless AC mode and a completely unusable 4 dBm (2mW!!!) in wireless N mode. This thing is supposed to be capable of the 100mW US maximum (I thought), why such the disparity? Have I configured something incorrectly or is it a bug?
There are 3 USB wifi adapters attached to this Pi (2X Alfa AWUS036ACM MT7612U chipset & 1X Alfa AWUS036ACHM MT7610U chipset) and only the adapter with the MT7610U chipset is having issues with tx power. All devices are powered by a 3amp USB powered hub(s) and the issue persists whether directly connected to the Pi or through a USB hub. The issue persists if the MT7610U adapter is the only device attached to the Pi. When I'm sitting next to it tx speeds are a little low (there's room for adjustment) but that's not my major concern at the moment.
I've modified the etc/wireless/config by changing the 18dBm to 20/22/30dBm, whatever, it has no bearing on the transmit power even after a network reload and/or system reboot. I'm under the impression this is actually hardcoded into the firmware so editing that particular setting is useless? How do I correct this?
Here is what iwinfo tells me. Below that is the /tmp/run/hostapd-phy3.conf for the MT7610U adapter.
wlan3 ESSID: "YourWifiPasswordSucks"
Access Point: 00:C0:CA:XX:XX:XX
Mode: Master Channel: 48 (5.240 GHz)
Center Channel 1: 42 2: unknown
Tx-Power: 18 dBm Link Quality: 70/70
Signal: -36 dBm Noise: unknown
Bit Rate: 292.5 MBit/s
Encryption: WPA2 PSK (CCMP)
Type: nl80211 HW Mode(s): 802.11nac
Hardware: unknown [Generic MAC80211]
TX power offset: unknown
Frequency offset: unknown
Supports VAPs: yes PHY name: phy3
------------------------------------------------------------------------------------
driver=nl80211
logger_syslog=127
logger_syslog_level=2
logger_stdout=127
logger_stdout_level=2
country_code=US
ieee80211d=1
ieee80211h=1
hw_mode=a
beacon_int=100
dtim_period=2
channel=48
chanlist=48
noscan=1
tx_queue_data2_burst=2.0
ieee80211n=1
ht_coex=0
ht_capab=[HT40-][SHORT-GI-20][SHORT-GI-40][RX-STBC1]
ieee80211ac=1
vht_oper_chwidth=1
vht_oper_centr_freq_seg0_idx=42
vht_capab=[SHORT-GI-80][RX-ANTENNA-PATTERN][TX-ANTENNA-PATTERN][RX-STBC-1][MAX-A-MPDU-LEN-EXP3]
radio_config_id=b9921f8c8f997ecd6fc45f6f3e2f880f
interface=wlan3
ctrl_interface=/var/run/hostapd
bss_load_update_period=60
chan_util_avg_period=600
disassoc_low_ack=1
skip_inactivity_poll=0
preamble=1
wmm_enabled=1
ignore_broadcast_ssid=0
uapsd_advertisement_enabled=1
utf8_ssid=1
multi_ap=0
wpa_passphrase=XXXXXX
wpa_psk_file=/var/run/hostapd-wlan3.psk
auth_algs=1
wpa=2
wpa_pairwise=CCMP
ssid=YourWifiPasswordSucks
wpa_disable_eapol_key_retries=0
wpa_key_mgmt=WPA-PSK
okc=0
disable_pmksa_caching=1
dynamic_vlan=0
vlan_naming=1
vlan_file=/var/run/hostapd-wlan3.vlan
config_id=1fac86c578ade03c5d2bd07a4c3516aa
bssid=00:c0:ca:XX:XX:XX