[BrainSlayer]

the channel collision check is a requirement by the wifi certification. this is why broadcom maybe made this. this is also why 40 mhz channels often only work in 5 ghz very good. consider. even if you get 40 mhz to run in 2.4 ghz it would be often slower than 20 mhz if another network is running in the same frequency. this is something which maybe should be considered before blaming broadcom or the wifi organisation.

for atheros chipsets i implemented a feature to disable this behaviour. you can force 40 mhz or stay in 20/40 dynamic mode which is the default for most vendors (except ralink, which wonderfully ignores everything )

[LJinFLA]

BrainSlayer,

I have been researching this for some time and have seen a couple of people posting this result on various build threads but no on ever seems to address the issue. THus I will start here and possibly post another thread.

I am running an E3000 and I have tested this twice on each of these:

dd-wrt.v24-14929_NEWD-2_K2.6_std_usb_ftp-e3000
dd-wrt.v24-16785_NEWD-2_K2.6_std_usb_nas-e2k-e3k
dd-wrt.v24-16785_NEWD-2_K2.6_big-nv60k
dd-wrt.v24-21286_NEWD-2_K2.6_big-nv60k
dd-wrt.v24-22118_NEWD-2_K2.6_big-nv60k (no Wireless)
KONG - usb-ftp-samba3-dlna-nv60k-broadcom 20805
KONG - usb-ftp-samba3-dlna-nv60k-broadcom-22200

When I say I have tested this twice, I mean I flashed the 14929 trailed, then 16785 e2k-e3k, then the 16785 nv60K, and then tested each of the nv60k builds listed above. I followed the 30/30/30 before and after each with proper 5 min wait times. I did this on two separate ocaisions starting over at the trailed build. All loaded fine, and each worked with the exception of the 22118 build which had no wireless, and the following problem on all the others.

I use a tool called inSSIDer3 by Metageek to view the band spectrum of the 2.4 and 5Gz bands and gather info about the Wifi found there. great tool by the way. The problem is that on all of them since the first nv60k build at 16785, regardless of the settings for channel, bandwidth, upper or lower on the 5gz band (using mixed mode), the actual transmitted frequency is channel 36 and is only 20Mhz wide. On a couple of the builds if I set everything to auto except the 40Mhz setting it would actually set up a 40Mhz wide transmission on 157+161 but could not move this anywhere else on the band by setting the channel settings differently because it would always then jump to channel 36, 20Mhz.

Based on this testing, it appears that this problem started with the nv60k builds on the E3000 and is inherent in all of them. IF this channel 36 20Mhz only problem has been reported in this way earlier I have not found it other than a few partial reports of 5Gz not working, or channel 36 only as above but not pointing out that channel 36 only works as 20Mhz wide even if set 40Mhz. Perhaps most people don't use a tool like inSIDDer3 to view the actual transmission from the router.

This did not happen on the pre nv60k firmware so I will likely go back to this unless someone can point me to a thread that explains how to fix this problem. Any Help?

Lee

***UPDATE***
After reading another poster using 22118 nv60k on an E3000 he claimed it worked. What I noticed was he had his 5Gz band set to N-only. So I went back and tested N-only and NA-mixed and sure enough, these worked just fine. The problem described above seems to only be a problem in fully Mixed mode. Don't know if that helps or not. I need N but would like to offer G on 5Gz but for now I will move forward to a later nv60k build and use NA-Mixed or N Only in the hopes of getting Mixed mode fixed in a future release.