Defective RT-N66U?

[revacuate]

I'm in DevOps. Not a noob, not an expert on routers. - This is my first dual band.

Purchased slightly used RT-N66U from amazon.com because I like to hack on Unix-based machines (dd-wrt.)

Put RT-N66U in same place where my DIR-655 was functioning just fine. When connected via WiFi, can't get more than about 15 feet from the device before the signal is lost.

Here's what I did:

Without really testing the functionality first, I upgraded the CFE to v1.0.1.3 to have 64K NVRAM.

Upgraded build to K2.6 dd-wrt build, found a few problems.
Upgraded build to K3.X dd-wrt build, seemed working fine at first, but try to walk 15 feet away with wireless and loose signal.
Started trying a lot of different builds, from Merlin's to KingKong's, to older straight up dd-wrt ones. All of them seem to have the same problem with distance from the device.
Returned to ASUS's factory build, same problem.

• 
  Connecting wirelessly works fine very close to the router.

• 
  Turning off 2.4GHz band and using only 5GHz did not fix the problem, nor vise-versa.

• 
  Changing channels to ones not being used by my neighbors did not make a difference.

• 
  Made sure to 30/30/30 reset many times. - Also used the WPS button method of holding it for 5 seconds during power-on.

Does anybody have any advice on this? Am I over-looking something? Am I dealing with a defective device?

It has a broadcom5300 CPU, which I did not seem to be able to find much about in the forums.

P.S. Do people generally set both band's SSIDs to the same name or to different names?

 

[RMerlin]

Use two different SSIDs - it will make it easier to troubleshoot which band i having issues.

If it's the 2.4 GHz band, make sure it's set to 20 Mhz to reduce the risk of interference. If even on the 2.4 GHz band you can't connect beyond 15 feet, then I suspect it's a hardware issue (maybe doublecheck that the antennas are properly screwed in, just in case).

Use a tool such as InSSIDer (Windows) or Wifi Analyzer (Android) to check the actual signal strength.

 

[jlake]

Remove your old wireless profiles on computer. Update the wireless adapter driver on your computer ( if possible).

For testing purposes, move the Asus router to an ideal location.

 

[TonyH]

Hi,
If you check the RF signal with something like inSSIDer is it really weak? What's the reading? Are antenna connectors tight, not loose? Have spare AC adapter to try? I never
use stock adapters, have own beefy ones to use.

 

[revacuate]

Use two different SSIDs - it will make it easier to troubleshoot which band i having issues.

If it's the 2.4 GHz band, make sure it's set to 20 Mhz to reduce the risk of interference. If even on the 2.4 GHz band you can't connect beyond 15 feet, then I suspect it's a hardware issue (maybe doublecheck that the antennas are properly screwed in, just in case).

Use a tool such as InSSIDer (Windows) or Wifi Analyzer (Android) to check the actual signal strength.

Remove your old wireless profiles on computer. Update the wireless adapter driver on your computer ( if possible).

For testing purposes, move the Asus router to an ideal location.

Hi,
If you check the RF signal with something like inSSIDer is it really weak? What's the reading? Are antenna connectors tight, not loose? Have spare AC adapter to try? I never
use stock adapters, have own beefy ones to use.

Thank you sirs. I made sure about 20Mhz, I disabled 5GHz again and ran tests with 2.4GHz only on several more builds to be extra positive. Each time I removed existing saved connections on my client devices, (a Macbook Pro and a Dell Ubuntu laptop.) All had the same result:

I installed Analyzer on my S4 Droid and took readings from all around my property inside and outside the house. I first used my working DIR-655 to get a standard, it gave off anywhere between -40 to, at the far extents of my property, -80. I then turned it off and tried with the RT-N66U. I gave the RT-N66U the extra advantage of being the middle of a large room. It gave off never more than -70 right next to the router, and -0 anywhere within 0 to 15-20ft.

Same result: get 15 feet away through a thin wall, or 20-25 feet away with direct line of site - it entirely looses the signal. It even drops the signal fairly frequently while sitting directly next to the router.

I took off each antenna and inspected it carefully and put them back on.

Thanks again guys, I think this means it's defective, although it is hard to imagine what kind of hardware defect would still allow it to work mediocrely close up. At least I know now.

 

[mikeg]

I see you tried a lot of f7w:s , why not try Tomato USB Shibby ?
I had trouble getting a brand new N66U to just set it up initially. When I installed the Tomato everything worked.
Use different SSID:s so you can set apart the bands.

I'm in DevOps. Not a noob, not an expert on routers. - This is my first dual band.

Purchased slightly used RT-N66U from amazon.com because I like to hack on Unix-based machines (dd-wrt.)

Put RT-N66U in same place where my DIR-655 was functioning just fine. When connected via WiFi, can't get more than about 15 feet from the device before the signal is lost.

Here's what I did:

Without really testing the functionality first, I upgraded the CFE to v1.0.1.3 to have 64K NVRAM.

Upgraded build to K2.6 dd-wrt build, found a few problems.
Upgraded build to K3.X dd-wrt build, seemed working fine at first, but try to walk 15 feet away with wireless and loose signal.
Started trying a lot of different builds, from Merlin's to KingKong's, to older straight up dd-wrt ones. All of them seem to have the same problem with distance from the device.
Returned to ASUS's factory build, same problem.

• 
  Connecting wirelessly works fine very close to the router.

• 
  Turning off 2.4GHz band and using only 5GHz did not fix the problem, nor vise-versa.

• 
  Changing channels to ones not being used by my neighbors did not make a difference.

• 
  Made sure to 30/30/30 reset many times. - Also used the WPS button method of holding it for 5 seconds during power-on.

Does anybody have any advice on this? Am I over-looking something? Am I dealing with a defective device?

It has a broadcom5300 CPU, which I did not seem to be able to find much about in the forums.

P.S. Do people generally set both band's SSIDs to the same name or to different names?

 

[RMerlin]

Thanks again guys, I think this means it's defective, although it is hard to imagine what kind of hardware defect would still allow it to work mediocrely close up. At least I know now.

Could be a burned out amp, or the inside antenna wiring being disconnected.

Considering this was an open box, it's not unlikely - I would get it replaced.

 

[TonyH]

Hi,
Some digital circuits (mainly chips, active components) can get damaged by static discharge. Things can get partially damaged to a point of limping being unable to run at full rated specs.(which will fail any time sooner than normal life span) In my working days I had a chance to look at static damaged things under microscope, comparing damaged for good, partially damaged still working, perfectly good one. Static damage can occur any time any where during handling. I have a habit of touching the desk top case when opening or touching various units first time. When working on a board or assembling a unit like desk top PC, I use anti-static strap and mat which is grounded with 10MegOhm resistor. Just old habit. Maybe that router is one suffered a such static zap.

 

[revacuate]

Update

For anyone who's wondering, I purchased a new version of the RT-N66U and put it in the same place and flashed it with the same firmware and did not have the same problem. (It really was defective hardware.)

Thanks again guys!