[RT-AC86u]5ghz channel issues

[Sildur]

Hey there, I hope this is the right forum section for this, new here.

So I recently got an asus RT-AC86u and have some issues with it's 5ghz channels. On both stock firmware and merlinWrt 384.7_2.
Whenever I select a channel higher than 112 it only uses one channel / band frequency, if that's what this is called, see the attached screenshots.
Is this supposed to happen? Because my crappy modem from my ISP is able to go all the way up to channel 128 and still make use of another channel. So with only my modem running in router mode I'm able to make full use of channel 116 and 124.
Meanwhile channel 124 and 128 are missing on my RT-AC86u, it jumps straight from 116 to 132. Channel 132 and 136 also don't seem to work, when selected my network just auto defaults to whatever it feels like, most of the time it auto jumps to channel 40 or 52 instead.

The extension channel is also unavailable all the time, or rather only auto is available, not sure if that's intended either.

Could this be an issue with region codes being wrong? I live in Switzerland.

 

[RMerlin]

The extension channel is also unavailable all the time, or rather only auto is available, not sure if that's intended either.

This is normal. The 5 GHz band channel specs work a bit differently from the old legacy 2.4 where you could chose whether the control channel would be below or above. The 5 GHz band doesn't really use two separate channels, it uses one single channel, but with a configurable width (20, 40, 80 or 160 MHz).

Meanwhile channel 124 and 128 are missing on my RT-AC86u, it jumps straight from 116 to 132. Channel 132 and 136 also don't seem to work, when selected my network just auto defaults to whatever it feels like, most of the time it auto jumps to channel 40 or 52 instead.

Not every clients support DFS channels. Channel availability is subject to region as well as DFS scanning, which can disable channels not cleared for operation.

 

[Sildur]

Not every clients support DFS channels. Channel availability is subject to region as well as DFS scanning, which can disable channels not cleared for operation.

That much I know, but it just seems weird to me that my crappy modem supports more, or rather different channels compared to my rt-ac86u. So I guess my 5ghz network only operates on channel 116 because 120, 124 and 128 are missing, for whatever reason.
My modem is the UPC ConnectBox, https://www.upc.ch/pdf/support/manuals/en/internet/ConnectBox/connect-box-manual.pdf

 

[RMerlin]

That much I know, but it just seems weird to me that my crappy modem supports more, or rather different channels compared to my rt-ac86u.

Your modem might be configured for a different region than your router and therefore support different channels.

 

[Sildur]

Your modem might be configured for a different region than your router and therefore support different channels.

Since I bought it here, in Switzerland, I guess it would be set to EU, which should support channels between 120-128. Unless ASUS didn't feel like it.

 

[ColinTaylor]

Since I bought it here, in Switzerland, I guess it would be set to EU, which should support channels between 120-128. Unless ASUS didn't feel like it.

The problem with channels 120-128 in the EU is that those channels are used by weather radar. Therefore any device that wants to use those channels has to listen on that channel for at least 10 minutes to make sure it is clear before it can use it. As most owners of WiFi devices would not want to wait for 10 minutes before being able to use their devices it is common for manufacturers to ignore those channels.

 

[RMerlin]

Since I bought it here, in Switzerland, I guess it would be set to EU, which should support channels between 120-128. Unless ASUS didn't feel like it.

Switzerland has also their own channel definitions, so it depends on whether the manufacturer uses the broader EU region, or the more specific Swiss one.

 

[Grisu]

Sorry to say but Asus is just lazy and closing allowed channels 120-128 instead of doing a bit more engineering. All my EU modem-routers will support all channels, only Asus wont!
There is no Asus region Swiss so you have it set to EU and 120-128 are not available so and you got much higher transmission levels in Swiss than EU, but you wont have them on your 86U ...

5G uses broader channels only in pairs shown for 40MHz and in brackets () for 80MHz and [] even 160MHz: [(36+40, 44+48), (52+56, 60+64)], [(100+104, 108+112), (116+120, 124+128)], (132+136, 140+144), nonEU (149+153, 157+161), 165
So you can clearly see ch. 116 could only use unsupported ch. 120 and so 40 or 80MHz are not possible with Asus.