Want to open that thread as a separate thread to the existing ones Questions/Answers which are all over the place on the forum and in the wild which are related to correct configuration/issues with MR8300.
I used 21.02.0-rc4 and a snapshot (dated 30th August 2021) with the same problems (or are they a genuine problems I dunno!).
Radio0 (5Ghz) - Is it a hardware capability that module is supporting only 20MHz channel width ? Despite if 40 or 80 is set via the luci it keeps using 20MHz (tested with Wifi analyzer). Or is that config or certain config pattern related?
Radio0 - I found in this thread that max tx power 30dBm should be supported and to get it available certain config pattern should be met (like setting Country manually, channel etc). I tried setting country to IE, US, CA, GB, IN - the max I was able to get is 26dBm on that module, with some countries even 23dBm or 19dBm. Also was changing channels and channel width with no luck getting beyond 26dBm. Can someone who was able to boost it beyond 26dBm share theirs config pattern ?
Radio1 (2.4Ghz) - max tx power on 20.02-* is 20dBm with any settings I tried to far. However on 19.07.08 (EA8300) with channel width 20MHz it is possible to set Radio1 to 30dBm. I am not insisting on that 19.07.08 is saying me truth as firmware isn't supposed to be installed on MR8300, but perhaps someone can expand a little bit on this question and provide the answer whether it should be supporting 30dBm or not? And if it is then how to fire it up on 20.02-* ?
Radio2 (5Ghz) - max tx power is 23dBm in every firmware I tried to far, with various countries/width combinations getting even smaller values. Is 23dBm max supported tx power on that module?
Very interesting why on mine all of the above except point 4 are not the same. I didn't try with 21.02.0-rc3 yet though so hopefully that is the case, I will do that later.
What is yours MR8300 revision version? Ive got rev1.1.
Are you able to post your wireless package config?
Thanks a lot
I tried with 21.02.0-rc3 (pure reflash from within OEM firmware so no leftovers from previous config). And it is still the same:
Radio0 is configured for 80MHz channel width but Wifi Analyzer identifies it as 20Mhz.
Radio0 max tx power is 26dBm
Radio1 max tx is 20dBm.
Reboot isn't making any difference.
My guess that either I am using different revision and that is potentially causing that OR I need to set specific Country or channel or something else to get the same performance as you have. Sample of wireless package config would be highly appreciated.
Thanks.
So I finally figured out what is wrong here. So, step by step (follow me):
The reason of not getting certain tx power is related to default country. Once again - default. If setting country manually to CA then that won't work.
When I am using default country (I am based in IE) it is somehow assigns IE to Radio0, and GB to Radio1 and Radio2. Not sure how that is happening, perhaps by geo lookup of my public IP, or by scanning ether... Just guessing.
There are certain regulation in every country what max TX power on what band is allowed. For detailed table please see this article.
From above article - it appears that not that many countries support 1000mW (30dB) on 2.4Ghz (b band). CA is one of those who support.
Not every country support 1000mW on 5Ghz either. But many. CA do support for instance.
If you set Country manually to CA on Radio0 that won't work, I was getting 23dBm in that case even after reboot.
Solution is to:
Set all interfaces to "driver default" country
use iw reg set CA, followed by wifi down & wifi up
After above steps all interfaces will be defaulted to Country CA and 30 dBms will become available on Radio0 & Radio1.
above steps won't survive reboot though. For getting default country set on startup simply edit /etc/rc.local file and add /usr/sbin/iw reg set CA there. Reboot and check.
I think there was already loads of confusion around that dB setting in Developers section thread somewhere in the forum, if someone want they can share solution there. Cheers.
Upd: 30dBm on Radio0 won't work on channel 100 btw. If switching manually to channel 149 then it is working. Or when using auto channel (for me it gets defaulted to 149). I think that is also somehow related to country specific regulations. For instance for CA:
36, 40, 44, 48 - 200mW
52, 56, 60, 64 - 1000mW
149, 153, 157, 161 - 4000mW
To legally conform to regulations - yes, absolutely. But from OpenWRT perspective I don't believe there are any difference in setting country which is not the country where you live. Or am I wrong?
My investigation was done purely to get to the bottom why 30dBm wasn't available to me.
But I don't think setting higher TX is giving me any benefit here, maybe it would if I would have clients with high TX from theirs end... WiFi is bidirectional. Clients cannot authenticate with AP even if RSSI is less than -90dBm but distance is too far. My understanding is that auth packets/frames aren't reaching AP due to a low TX on the clients.