MT7662E txpower problem

Hi all!

I am using a ZBT-WE826 (16M) device. I've configured the 5 GHz wifi and it seems to work, but the TX power is extremely low (3 dBm). I have tried several settings (channels, width, power) in luci and command line, but nothing changes.
If I move my phone very close to the router then the network shows up, but I can't connect. Scanning also works, so the HW seems to be correct.

Can anybody please tell me what the problem can be? I am out of ideas.

Some more info:

global
country HU: DFS-ETSI
	(2402 - 2482 @ 40), (N/A, 20), (N/A)
	(5170 - 5250 @ 80), (N/A, 20), (N/A), AUTO-BW
	(5250 - 5330 @ 80), (N/A, 20), (0 ms), DFS, AUTO-BW
	(5490 - 5710 @ 160), (N/A, 27), (0 ms), DFS
	(57000 - 66000 @ 2160), (N/A, 40), (N/A)

root@OpenWrt:~# iw wlan0 set txpower fixed 2000
root@OpenWrt:~# iwinfo wlan0 info
wlan0     ESSID: "NETEZNI.AKARSZ.HU-5"
          Access Point: 78:A3:51:4F:18:B9
          Mode: Master  Channel: 36 (5.180 GHz)
          Tx-Power: 3 dBm  Link Quality: unknown/70
          Signal: unknown  Noise: unknown
          Bit Rate: unknown
          Encryption: WPA2 PSK (CCMP)
          Type: nl80211  HW Mode(s): 802.11bgnac
          Hardware: 14C3:7662 14C3:7662 [Generic MAC80211]
          TX power offset: unknown
          Frequency offset: unknown
          Supports VAPs: yes  PHY name: phy0
root@OpenWrt:~# 

What is the output of

iw phy

in particular the section(s) on "Frequencies" that shows channels, power limit, and "radar detection"?

/etc/config/wireless (with sensitive data removed) would be helpful as well

Wiphy phy0
	max # scan SSIDs: 4
	max scan IEs length: 2243 bytes
	max # sched scan SSIDs: 0
	max # match sets: 0
	max # scan plans: 1
	max scan plan interval: -1
	max scan plan iterations: 0
	Retry short limit: 7
	Retry long limit: 4
	Coverage class: 0 (up to 0m)
	Available Antennas: TX 0x3 RX 0x3
	Configured Antennas: TX 0x3 RX 0x3
	Supported interface modes:
		 * IBSS
		 * managed
		 * AP
		 * AP/VLAN
		 * monitor
		 * mesh point
	Band 1:
		Capabilities: 0x1ff
			RX LDPC
			HT20/HT40
			SM Power Save disabled
			RX Greenfield
			RX HT20 SGI
			RX HT40 SGI
			TX STBC
			RX STBC 1-stream
			Max AMSDU length: 3839 bytes
			No DSSS/CCK HT40
		Maximum RX AMPDU length 65535 bytes (exponent: 0x003)
		Minimum RX AMPDU time spacing: 4 usec (0x05)
		HT TX/RX MCS rate indexes supported: 0-15
		Frequencies:
			* 2412 MHz [1] (20.0 dBm)
			* 2417 MHz [2] (20.0 dBm)
			* 2422 MHz [3] (20.0 dBm)
			* 2427 MHz [4] (20.0 dBm)
			* 2432 MHz [5] (20.0 dBm)
			* 2437 MHz [6] (20.0 dBm)
			* 2442 MHz [7] (20.0 dBm)
			* 2447 MHz [8] (20.0 dBm)
			* 2452 MHz [9] (20.0 dBm)
			* 2457 MHz [10] (20.0 dBm)
			* 2462 MHz [11] (20.0 dBm)
			* 2467 MHz [12] (20.0 dBm)
			* 2472 MHz [13] (20.0 dBm)
			* 2484 MHz [14] (disabled)
	Band 2:
		Capabilities: 0x1ff
			RX LDPC
			HT20/HT40
			SM Power Save disabled
			RX Greenfield
			RX HT20 SGI
			RX HT40 SGI
			TX STBC
			RX STBC 1-stream
			Max AMSDU length: 3839 bytes
			No DSSS/CCK HT40
		Maximum RX AMPDU length 65535 bytes (exponent: 0x003)
		Minimum RX AMPDU time spacing: 4 usec (0x05)
		HT TX/RX MCS rate indexes supported: 0-15
		VHT Capabilities (0x018001b0):
			Max MPDU length: 3895
			Supported Channel Width: neither 160 nor 80+80
			RX LDPC
			short GI (80 MHz)
			TX STBC
		VHT RX MCS set:
			1 streams: MCS 0-9
			2 streams: MCS 0-9
			3 streams: not supported
			4 streams: not supported
			5 streams: not supported
			6 streams: not supported
			7 streams: not supported
			8 streams: not supported
		VHT RX highest supported: 0 Mbps
		VHT TX MCS set:
			1 streams: MCS 0-9
			2 streams: MCS 0-9
			3 streams: not supported
			4 streams: not supported
			5 streams: not supported
			6 streams: not supported
			7 streams: not supported
			8 streams: not supported
		VHT TX highest supported: 0 Mbps
		Frequencies:
			* 5180 MHz [36] (20.0 dBm)
			* 5200 MHz [40] (20.0 dBm)
			* 5220 MHz [44] (20.0 dBm)
			* 5240 MHz [48] (20.0 dBm)
			* 5260 MHz [52] (20.0 dBm) (radar detection)
			* 5280 MHz [56] (20.0 dBm) (radar detection)
			* 5300 MHz [60] (20.0 dBm) (radar detection)
			* 5320 MHz [64] (20.0 dBm) (radar detection)
			* 5500 MHz [100] (27.0 dBm) (radar detection)
			* 5520 MHz [104] (27.0 dBm) (radar detection)
			* 5540 MHz [108] (27.0 dBm) (radar detection)
			* 5560 MHz [112] (27.0 dBm) (radar detection)
			* 5580 MHz [116] (27.0 dBm) (radar detection)
			* 5600 MHz [120] (27.0 dBm) (radar detection)
			* 5620 MHz [124] (27.0 dBm) (radar detection)
			* 5640 MHz [128] (27.0 dBm) (radar detection)
			* 5660 MHz [132] (27.0 dBm) (radar detection)
			* 5680 MHz [136] (27.0 dBm) (radar detection)
			* 5700 MHz [140] (27.0 dBm) (radar detection)
			* 5745 MHz [149] (disabled)
			* 5765 MHz [153] (disabled)
			* 5785 MHz [157] (disabled)
			* 5805 MHz [161] (disabled)
			* 5825 MHz [165] (disabled)
	valid interface combinations:
		 * #{ IBSS } <= 1, #{ managed, AP, mesh point } <= 8,
		   total <= 8, #channels <= 1, STA/AP BI must match, radar detect widths: { 20 MHz (no HT), 20 MHz, 40 MHz, 80 MHz }

	HT Capability overrides:
		 * MCS: ff ff ff ff ff ff ff ff ff ff
		 * maximum A-MSDU length
		 * supported channel width
		 * short GI for 40 MHz
		 * max A-MPDU length exponent
		 * min MPDU start spacing
	Device supports VHT-IBSS.
root@OpenWrt:~# cat /etc/config/wireless 

config wifi-device 'radio0'
	option type 'mac80211'
	option hwmode '11a'
	option path 'pci0000:00/0000:00:00.0/0000:01:00.0'
	option legacy_rates '1'
	option country 'HU'
	option log_level '4'
	option rxantenna '1'
	option txantenna '2'
	option channel '36'
	option htmode 'VHT40'
	option txpower '20'

config wifi-iface 'default_radio0'
	option device 'radio0'
	option mode 'ap'
	option ssid 'NETEZNI.AKARSZ.HU-5'
	option macaddr '78:A3:51:4F:18:B9'
	option network 'lan'
	option encryption 'psk2'
        option key '*********************'

are the only "surprising" things I see there. Other than that, it looks like your device is capable of 20 dBm output on channels 36-64 and, if DFS doesn't push you out, 27 dBm on channels 100-140.

In my experience with other devices, the "antenna" fields aren't set to allow the chipset to use all that it has available. Available Antennas: TX 0x3 RX 0x3 suggests that there are two antennas (0x3 is two bits wide). The settings you have seem to restrict transmit to a single antenna, which might "confuse" the driver and/or chip.

I have experimenting with a lot of things and those antenna settings were left in the config file. If I remove them nothing changes.

Everything seems to be fine, just the wifi does not work. The other 2.4G interface works just fine and it also allows me to set the TX power.

I have not worked with MediaTek hardware myself, but I have seen a lot of mention of newer drivers resolving certain issues. Perhaps there is something helpful in

Did you ever get the performance issues fixed with the 826?

I've got the same router and am seeing the exact same issue....

I have similar problem with ZBT-WE826.
I think that I found the source of problem. Driver cant read settings from eeprom.
I solved it by adding section:

&pcie0 {
        mt76@0,0 {
                reg = <0x0000 0 0 0 0>;
                mediatek,mtd-eeprom = <&factory 0x8000>;
                ieee80211-freq-limit = <5000000 6000000>;
        };
};

into file "ZBT-WE826.dtsi".

Thank you for sharing. I have a similar (?) issue with mt7610e, but this .dts is looking good - right?

Yes. Your case is not my case. Btw, after a patch I achieved power 13dbm. I am not sure that higher power is possible.

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