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My "better" router has 5GHz channels - 36,40,44,48,149,153,157,161

My not so much better router has 5GHz channels

  • 36,40,44,48,52,56,60,64,100,104,108,112,116,132,136,149,153,157,161

I am confused as to why the least expensive one has more channels compared to the "better" one. And also curious with which channel is best to use and what the difference is if I pick a lower channel compared to a higher numbered channel.

5 Answers 5

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The channels that your "better" router has omitted are what is known as the dynamic frequency selection or DFS channels. These channels have been allows by the FCC for use, but they must employ a means of detecting and shifting off the channel if they detect another licensed use of the spectrum (namely some forms of weather radar and very limited military use).

Many enterprise deployments will avoid these channels if possible for the same reason.

It sounds the like the vendor of your "better" router has decided to avoid those complexities and simply ignore that they exist. This still leaves you eight non-overlapping channels which is five more than you have in 2.4 GHz (which has only three non-overlapping channels) and far more than you need in any residential/consumer deployment.

As to which to use, download a copy of inSSIDer and pick the one where you see no or the lowest signal strength in use.

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  • When you say my vendor "decided to avoid those complexities" , you mean that the router ignores the fact that weather radar and military may use these channels and just allows me to pick them anyway?
    – Aaron
    Dec 25, 2013 at 5:06
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    No, the DFS channels require that the AP/router using them needs to be able to identify when such a device is/starts operating in the area and "dynamically" change to a different channel. Your better router avoids this complexity by simply not allowing you to use these channels...since you can't use them it doesn't need to detect if such devices are operating in the same RF space.
    – YLearn
    Dec 25, 2013 at 5:25
  • Ah, so the channels it uses are already omitted. So I best try to match those channels to the older router that shows everything. It's Netgear btw. I also thought the higher or lower channels affected range, I wasn't certain about that.
    – Aaron
    Dec 25, 2013 at 5:27
  • Highly recommend using inSSIDer, if you can move to a clear channel none of your neighbors are using, you'll be in good shape!
    – MDT Guy
    Dec 27, 2013 at 20:56
  • A user tried to edit and I felt it was at least worth a comment. The license model for inSSIDer has changed and now the personal edition (which is a bit trickier to find) license costs $20. The office license is $149.
    – YLearn
    Aug 3, 2016 at 17:50
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The best channel to use is the lowest channel that has a high transmit power. Lower frequencies penetrate walls more easily, and there is a significant difference between channel 36 (5180Mhz) and channel 165 (5825Mhz).

However up until 2014 there were limits on transmit power for the lower frequencies, so depending on your router you may need to use a higher channel to get larger transmit power.

So in reality you should just try channels within the various 5Ghz bands and see which gives a better signal. Then choose the lowest channel within that band.

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  • Even after 2014, there seem to still be limits in the US: apps.fcc.gov/kdb/…
    – huyz
    Dec 31, 2021 at 18:09
  • The higher bands have higher power limits because they don't penetrate as well so cause less interference. I don't think you are gaining anything here with power.
    – Nimrod
    Jul 27, 2022 at 1:45
  • There will ALWAYS be limits on RF output power. Either for interference reasons, or for exposure reasons. That being said, while yes, lower frequencies penetrate walls easier than higher can, you can hit weird harmonics, wave paths, and lobes depending on which frequency you use. Antenna orientation is also a HUGE factor. Getting the most out if you're wifi isn't as simple as 'always use these three channels(HUGE myth btw), and stick your tongue out to the left on tuesdays otherwise you might as well be on dialup'. Best thing to do is get an app that displays signal stats, and experiment.
    – Tank R.
    Oct 29, 2023 at 6:17
  • I would say these days it's probably better to just get a more powerful wifi router with the latest wifi standards rather than worrying about channels.
    – CpnCrunch
    Dec 8, 2023 at 0:26
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Your "better" router probably supports that fuller list of channels as well, but it doesn't show you those channels for manual channel selection. As @YLearn's Answer mentioned, those other channels (52-144) require DFS, which means that your router might not be able to use some of those channels even if you had picked them.

It's confusing to users if you let them manually pick a channel, and then you end up having to use a different channel anyway. It makes users feel like you lied to them when you let them manually pick a channel even if you knew you might not be able to honor their choice. And you sort of did lie to them. So better router vendors only let you manually pick the channels they know for sure they'll be able to use. To access any other channel, you just have to rely on automatic channel selection.

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  • Yeah didn't know what it meant. No documentation on it either. I assumed different channels gave better range but not sure. Will have to run inssider to be sure.
    – Aaron
    Dec 27, 2013 at 12:10
  • The failing is mostly in how DFS triggers are detected. Using your microwave can make DFS think you're interfering with aircraft radar and force a channel skip. Its kind of ridiculous, TBH. Also, different channels can give better performance (not necessarily range, though it's possible) based on how the RF energy at given frequencies disperses through the geometry and construction of your routers environment. Sidenote: 3, 6,and 9 are NOT the only channels you can use on 2.4, sometimes straddling busy channels is better, more people need to understand that... but RF is crazy compex
    – Tank R.
    Oct 29, 2023 at 6:24
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To answer the other half of your question, channels 149-161 will provide better range than 36-48. The higher band broadcasts at a stronger signal than the lower band (I believe this is due to the standard).

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  • 2
    This isn't necessarily true in all areas. This isn't due to the IEEE 802.11* standards, it's due to regional radio regulatory agencies (FCC, ETSI, etc.). So if the region you live in allows higher power in the upper band, the upper band is better. But if not, then it's not.
    – Spiff
    Dec 27, 2013 at 21:24
  • Very random for different locations. That's not a good standard..
    – Aaron
    Dec 27, 2013 at 23:32
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    Lower frequencies provide better penetration through walls, so choose the lowest channel you can.
    – CpnCrunch
    Dec 7, 2015 at 0:44
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    @CpnCrunch The difference in wall penetration between 2.4 and 5 GHz is significant (a factor of 2 - that's an octave). The difference between 5.2 and 5.8 GHz is not. Feb 24, 2019 at 3:36
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If you are in a house where your wifi needs to penetrate multiple walls and/or floors - choose a low channel. If your in a loft apartment or want your wifi to extend into the back yard with a near clean line of sight, choose a higher channel.

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