Yesterday I looked at the Wifi Analyzer app on my smartphone at home, and found that there was a pileup on channel 1 in the crowded 2.4 GHz band. I had switched us to channel 1 a few years ago, because it was then uncluttered.
One of our nextdoor neighbors was now on channel 1 with us. Maybe he got a new router. I’ll have to ask him next time I see him at the mailbox.
Another neighbor has the middle channel 6.
There are 13 wifi channels used on the 2.4 GHz band in the US. Channel 11 is the highest I could select on my old warhorse Linksys WRT54G router (802.11g protocol). That allows for signal spread up to channel 13 on the high side. Here are their frequencies:
1: 2.412 GHz
2: 2.417 GHz
3: 2.422 GHz
4: 2.427 GHz
5: 2.432 GHz
6: 2.437 GHz
7: 2.442 GHz
8: 2.447 GHz
9: 2.452 GHz
10: 2.457 GHz
11: 2.462 GHz
12: 2.467 GHz
13: 2.472 GHz
After I made the change, 2 out of 3 of our Roku boxes seemed to have trouble adapting to these new channel. I did a factory reset to get another one of them working. The other one didn’t like the channel even after a reset.
It occurred to me that our X10 video sender might be interfering. It also operates on the 2.4 GHz band, with 4 channel choices:
A: 2.411 GHz
B: 2.434 GHz
C: 2.453 GHz
D: 2.473 GHz
(Note that X10 channel A and Wifi channel 1 are almost the same, as are D and 13.)
I had set X10 on Channel D years before by trial and error. I hadn’t understood why D worked better at the time, but that frequency was as far away from the lower channels where our router was operating as it could get. It was jamming the high end of the band which we now occupied.
So I had to switch the X10 sender to a lower channel. Since our channel 6 neighbors’ router is physically much closer to the X10 sender, I elected to go with X10 channel A, to the possible detriment of our channel 1 neighbor.
The 2.4 GHz band is cluttered, Bluetooth, wireless phones use it, too. Microwave ovens really fritz it up.
A better solution than playing “2.4 keep away” is to get a newer router that uses the 5 GHz band (802.11n or 802.11ac).These routers should improve the performance of Plex as well. Or get a video sender/receiver on the 5.8 GHz band.
The best solution for streaming home media is Ethernet wiring (which I plan to do), but phones and tablets still need wireless.
I may get a newer router operating in the higher band (which can I see from another app is entirely unoccupied in our immediate neighborhood), then switch the X10 sender to whatever frequency is least used by the neighbors. I will also have the sender on only when we are actually using it.
The third Roku (model LT) was able to establish a link to the router with the X10 sender off. (Later note: I now have a Roku 3 using Powerline in the theater room rather than wire for Ethernet.)
By the way, X10 manufactures both the video sender/receiver and home automation items, but the two product lines have no technical relationship to each other. The X10 automation control protocol is sent over house wiring, and its associated wireless protocol operates on 310 MHz, far away from wifi frequencies.