Question on 5GHz Channels

[MysticGold04]

I have been trying to minimize interference with other neighbouring 5Ghz networks but does anyone know why the choices are limited to 36-48 and 149-161??

I have an ac68u and am running Merlin 384.18. Currently its set on ch 1 and ch 48... I have another ac68 that is running ddwrt, and that allows 52 and higher channels... Just curious.

 

[ColinTaylor]

The enable the other channels you have to select the option to enable DFS channels. I'm not sure exactly what the wording of that option is, it might be called Band II rather than DFS.

 

[MysticGold04]

Hmm, nope, no option like that shows for me. I'm going to guess that DFS channels aren't available on Merlin for this router, unless there might be an nvram command that might work to enable them?

 

[ColinTaylor]

Are you using a non-USA router by any chance? Different regions have different channel allocations.

 

[MysticGold04]

Nope.. USA router, and country is set to USA I've been doing some googling and it seems that the channels presented by the router are correct. Just strange that I can't select other valid channels for USA.

I think it's the same for John's firmware as well...

 

[ColinTaylor]

I suppose that if your router is a very old model it was never certified by the FCC to use the DFS channels. If you SSH into the router and issue this command what do you get?

nvram show | grep -E "wl1_acs_dfs=|territory_code|wl1_country_code|wl1_country_rev|wl1_chlist|wl1_acs_excl_chans"

Just a guess but I think if you set the 5GHz to "Auto" a checkbox appears about allowing DFS channels. Try ticking that box and applying it, and then see if you get any more channels appearing when you go back to manual channel selection.

 

[MysticGold04]

Here is the output:

wl1_acs_excl_chans=0xd0a5
wl1_chlist=36 40 44 48 149 153 157 161 165
size: 53713 bytes (11823 left)
wl1_country_rev=0
wl1_acs_dfs=0
wl1_acs_excl_chans_cfg=
wl1_country_code=US
wl1_acs_excl_chans_base=0xd0a5

I will try ticking the auto box and post back if there are any differences in the channels.

 

[MysticGold04]

I know we're comparing apples to oranges here, but here is the same output from one of my ddwrt routers...

size: 32728 bytes (32808 left)
wl1_country_rev=0
wl1_country_code=US

 

[ColinTaylor]

That does indeed appear to be the complete list of channels for region US/0. I don't know what region other US routers of the same model are using.

US (US/0) UNITED STATES
36 40 44 48 149 153 157 161 165

I'm guessing that your particular hardware revision was manufactured before the FCC started allowing use of DFS in the US.

I assume you tried doing a factory reset and nothing changed?

IIRC DD-WRT is naughty and allows you to override the burnt-in channel selection.