Channels not available for 40MHz; 80MHz and 160MHz @ 5GHz

I understand 100% of that, I merely thought OpenWrt let you set the 40 and 20.

If that's not the case, I agree the list is more confusing than other methods of listing channels used by other developers.

It only allows you to choose channels in the 20mhz range.

To select an 80 mhz channel you select the center frequency of the LOWEST 20 mhz channel and then select the bandwidth

pretty dumb huh..

Fun part is it will only actually work if you make a "valid" selection so the software already knows what is correct. it's just not in the UI.

if the selection is invalid the radio will not associate correctly.

So for mine channel selecting channel 116 and selecting 80Mhz should really just be channel 122

Yes, and then you set...20, 40, 80 or 160 - as I noted before, I thought this would allow the person to determine what [20Mhz] frequency "range(s)" was in use.

Whoa...are you saying that you only get 80 MHz if you select: 36,52,100,116,132 or 149 and then select 80 MHz?

Are you saying it fails otherwise????

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YES ! That is what I am saying.

if i select a different channel like 44 and set the width to 80 it fails.

So something has got to give.

(to be clear it does not fail it when saving the setting it just makes the radio not work)

basically you have to understand the bandpland and OpenWRT's odd implementation of the bandplan to setup your wireless network in the UI. My "Channel = bandwidth" solution would fix this.

I am a computer system engineer for a living. This is what I do and it took ME a wile to figure out what the issue was. Which is why I think we need to make this work more gooder :wink:


As am I; and now I'm curious to duplicate this...but I don't think occurs on 40 MHz devices (my test router).

well can you set it to 40Mhz and channel 40 or 56?

Yes, and it works.

and the radio associates properly?

If you choose channel 40 and 40mhz your center frequency is 5210 and that is not valid. (but it may be ubiquity valid) it is not industry standard

I think the options are emulate Ubiquiti, "store whatever they choose, calculate/use the correct base channel for the specified freq/width, hint at the conclusion (upper extension or lower extension)", or make the ui presentation adapt to width changes by greying out and shifting to a valid frequency.

1 Like be clear, I think I have production device set in that manner now - verify...I have 161 set at 40 MHz...which under your same issue should fail unless set to 157:


I was thinking about that. Greying out ones that will not work correctly. This would keep the same methodology but stop users from selecting "bad" frequencies.

A radio button to "Override" could allow for non standard settings for the tweakers.

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161 is in a weird place at the end. try 40 or 56.

Perhaps not even greying out, just lighting a "non-standard base channel for this channel width" mouseover warning bulb that explains the implication.

that would also work.

Maybe just color them green/red as appropriate

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That would be pretty intuitive and still non-restrictive. Sounds like a good path.

well where do we go from here?

Interestingly the same "rules" regarding channel and channel width apply to wifi6 and they were even nice enough to use odd number instead of even.

6Ghz band PLan