strange 5ghz issue - N66U

[Mr_Andy]

Hi
I have an Asus N66U, currently running latest Merlin 380.57

I thought I would put a post on this forum to see if anyone else has had problems using 5Ghz on this router?

I use two separate SSID's for 2.4 and 5ghz bands.

wifi performance over 5ghz seems much slower than on 2.4, even when sitting next to the router with full signal. using an app like speedtest.net for example I can get 45mb/s on 2.4ghz, but maybe only 10mb/s on 5ghz if it works at all, sometimes the app will say 'network error'. The devices I'm using are a Samsung Galaxy S3, and an iPad 3 and I get similar problem on both.

The only way I've found to have a stable working 5ghz is to change the 5ghz wireless mode on the router to 20mhz, and fix the channel to one of the four lower numbers 36, 40, 44 or 48 (anything above 48 and the Samsung or iPad cannot see my SSID at all). when setting 5ghz to 20 mode, it's as fast or faster than connecting over 2.4ghz with no problems. if I fix the wireless mode to 40 or 20/40 I get the slow performance again.

I'm not sure if it's the router or a problem with the devices I'm using, as 5ghz should work ok at 40 ?

by the way as this is my first post want to say 'Hi' and especially to Merlin for all his hard work on this.

thanks

 

[dlandiss]

We have installed about 20 N66U around St. Louis and use either Merlin or John's Fork firmware. One is 5 feet from where I am sitting, acting as my main gateway router. None have exhibited the symptoms you outlined.

Yes, combining 2 channels on the 5G band works well, although in most cases the extra speed is not needed. I agree that the lower 5G channels (2-digit) work better, much less congestion there.

If range is an issue try John's Fork for the N66U. Also be sure all 3 antennas are screwed in tight -- they have a tendency to loosen when they are rotated to get the tilt angle you prefer.

 

[ColinTaylor]

The only way I've found to have a stable working 5ghz is to change the 5ghz wireless mode on the router to 20mhz, and fix the channel to one of the four lower numbers 36, 40, 44 or 48 (anything above 48 and the Samsung or iPad cannot see my SSID at all).

I'm surprised that you can select any channels above 48! I certainly can't on my N66U. It was my understanding that the N66U is not certified for the upper channels in the EU and they can only be enabled by modifying the CFE.

Maybe those channels were enabled in the later firmwares (I'm running John's fork which is based on an older firmware).

Have you made any non-standard changes to the router?

 

[Mr_Andy]

Hi ColinTaylor

no changes made at all but on my 5ghz primary channel I have a whole range of numbers available in the drop-down list in the GUI. maybe it's worth resetting the router to factory settings again.

'extension channel' is simply 'auto', no other options available

 

[ColinTaylor]

Hi Mr_Andy,

'extension channel' is always 'auto' on mine too. So at least that's the same.

It is probably a good idea to do a factory reset and then do the minimum amount of setup that allows you to get into the router. Then check what the default values are.

You could always back up your config beforehand. Or better still use John's NVRAM utility as that is more flexible.

 

[mstombs]

I'm surprised that you can select any channels above 48! I certainly can't on my N66U. It was my understanding that the N66U is not certified for the upper channels in the EU and they can only be enabled by modifying the CFE.

Maybe those channels were enabled in the later firmwares (I'm running John's fork which is based on an older firmware).

In UK and Merlin 378.56_2 I have channels 36-64, 100-116, 132-140 available. I also use the lowest channel possible, the upper ones are required to operate in regulatory mode and I believe DFS is responsible for regular drops in connection - I also used to get log messages about 'radar detection'. I have updated the CFE using the tools on this site (to experiment with overclocking), but didn't deliberately fiddle with the country codes etc.