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Message-ID: <80556c56e69405d7c8f8bc3d57e2ba697074c660.camel@sipsolutions.net>
Subject: Re: every other wireless scan shows bogus (too low) signal strengths
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Bruno Dantas <dantas@airpost.net>, linux-wireless@vger.kernel.org
Date:   Thu, 01 Dec 2022 08:57:35 +0100
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References: <b48efa92-9eee-d491-1149-a7cee08300c0@airpost.net>
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On Wed, 2022-11-30 at 16:19 -0500, Bruno Dantas wrote:
> I have an X230 ThinkPad with coreboot and Intel Dual Band Wireless-AC
> 7265 card, which uses the iwlwifi kernel module. Module's wifi power
> saving is off (the default setting).
>=20
> When I scan for wifi hotspots at the command line, every other scan
> gives me bogus (too low) signal strengths and every other scan gives
> me expected signal strengths:

> [...]

> Does anyone know why this happens and how to fix it so that every scan sh=
ows the expected signal strengths?
>=20

I think this NIC might be switching antennas for scan every time.

If you're able to open it, it might be a good idea to check if they're
both connected well, almost seems like one might not be connected quite
correctly?

Not sure I have any better idea.

You could record debug data with trace-cmd [1] and then at least we
could confirm this is the case.

johannes

[1]
https://wireless.wiki.kernel.org/en/users/drivers/iwlwifi/debugging#tracing