Question Network Interference from desktop PC ?

[SyCoREAPER]

This goes into signal spectrums in ways that are way above my knowledgebase.

I have 3 bands active, a 2.4ghz, 5ghz and 6ghz. The desktop maybe 3 feet away hardwired.
If the desktop is running and I go a few rooms over no where I'd have no issues with the desktop off, I still have full bars on all my wireless devices but no internet. If I walk up to the router, I have internet again. This is ONLY an issue for 5ghz (AKA WiFi6). 2.4ghz works fine and 6ghz (WiFi 6e) doesn't reach worth a damn or have any meaningful benefits for 300Mbps Internet use, completely discounting network transfer, I know.

Now this is where any wireless communication knowledge has reached the end of the book for me.

I went into the router and for S&G's changed the Channel Width because I know something like 20hz is good for urban and congested areas with interference but the throughput isn't the best. Nothing. So I changed the Channel too. What do you know, I have internet. 20Mbps instead of 300Mbps but it's something. Tried 40hz and up and was iffy so in went back to 20hz.

Tried another channel, same as the original situation, but no internet. Tried another, the entire band went down and stopped broadcasting the SSID.

I found one channel on 20hz that gets me around a jumpy 200Mbps which I've compromised on but it's a bandaid, not a fix. Id prefer to go back to 160hz width like I was before and have stable speeds though.

So what could be the cause here?

• I am in a rural area with 0 devices that could be the cause otherwise.
• It only happens when the desktop is on.
• I know BT is 2.4ghz but I tried turning that off and as expected had no effect.
• It works close up.
• It works on certain channels and width combinations.
• I have my ShieldTV hardwired next to the TV without issues and swapped around there Ethernet ports so there isn't some rouge circuit/Ethernet controller in the router giving off interference.
• I have not rulled out interference from the PC because of the case. Coincidentally, the glass side panel is on the same side of the room as the router.

Last and most difficult option will be move the router further away but that still may not be solved based on the last bullet point above.

 

[BFG-9000]

Try unplugging, disabling the USB 3.0 ports or changing them to operate in USB 2.0 mode. They operate at 2.5GHz and can interfere with both high 2.4GHz, or low 5GHz channels as a harmonic. The earliest routers with a USB 3.0 port such as RT-AC68 actually lost wifi signal whenever an attached USB device was used, so all later models featured a very heavily shielded port with a RF can or copper tape covering all the internal traces leading to it. But of course the problem is still there if someone uses a poorly shielded USB cable!

Something in your PC is likely broadcasting 5GHz noise. Usually even if the CPU is operating in the 5GHz range it's not an issue as the heatsink shields it well enough, and your RAM is only running at 2GHz so shouldn't cause an issue. But you could always try temporarily unscrewing the wifi antennas off the desktop, and lining its glass side window with aluminum foil.

 

[bill001g]

The strangest thing about your issue is where you say.
You have strong signal level but no internet but you walk closer to the router and you get internet. Even more strange is it works fine with the desktop off.

First I would check if the desktop has wifi that you have disabled it.
There are 2 basic parts of a connection. You have the wifi part and you have the IP part. You can have a wifi connection with no ip addresses. Since the desktop pc only runs on wifi it should not interfere. It can in theory interfere with the IP addresses but it would always do that no matter the distance from the router.

You may have already done it but I would set different names for the 2.4,5, and 6ghz radios on your router. If they are the same the end device might be changing what it connects to without you knowing.

The discussion of channels gets complex fast so I will try to be brief..which I am not very good at.

On 2.4g you can only have 20 and 40mhz. 40mhz is best is you can get it to work.

5ghz is 20/40/80 and in some limited cases 160mhz will work. Many end devices do not support 160mhz because of the need to avoid things like weather radar. This also means if you set the router to use these restricted channels your end device might not see it.

6ghz you should always try to get 160mhz. Note it just "allows" 160mhz it does not force it. The router and end device should try to figure out what the best speed is.

Depends on the router and how the implement the channel number. Some kinda ignore it and use the 20/40/80 setting to override and other use the number.
https://en.wikipedia.org/wiki/List_of_WLAN_channels

As a example if you look down at the 5ghz table about halfway down. You will see if you set channel 40 it uses 20mhz. If you set channel 38 it uses 40mhz. Channel 42 uses 80mhz and channel 50 uses 160. The key thing to also note is the other columns that have the country. When you see DFS or tpc this means it might not always be able to use it depending on if something like weather radar is running. Also in some countries the radio output power is different depending on what channel you select.

This is so complex to really understand which is why most people just leave it all on auto and hope for the best.

Again your problem is very strange. If it just did not work well always then you worry about the radio channel stuff. Because it depends on the desktop being turned on I am not sure.

 

[JohnMGotts]

When did it start & what changed?

 

[SyCoREAPER]

To keep my response from killing 56k modems out there I'm going to tag instead of quote.

@BFG-9000
The USB part is interesting I never heard of that and is good for future reference. However I don't think that's the issue as it would kill the signal all the time no?
Funny you mention the foil. I was actually looking at where I could get large copper adhesive sheets last night. Didn't think to go more basic first. That's an excellent suggestion.

@bill001g
Ah I wish I mentioned I understand the chanel groupings/aggregation for the respective channel widths and save you some typing. Nevertheless that's an excellent explanation and im sure will at least help someone that comes across this.
As for DFS, I do use DFS channels usually because my router can switch to non-DFS channels if a broadcast happens and switch back. The rare occasions there are broadcasts the risk of a temporary drop doesn't bother me.

Your 'for example' section has me a bit confused, and I didn't know this, though. If certain channels are "bonded" to channel widths, shouldnt my router be not showing them if I select 20hz only mode? All channels where still showing in each width as well as obviously the allow all width option. For privacy reasons I'm not going to mention the brand but it is a very reputable one and not cheap, I think they go for $600-800. I know without the name that doesn't make it good because it's expensive but it is a top ranked router. I don't mention that btw to flex, only to emphasize it's not a cheapo router. But back to the point, I guess when I was selecting channels and losing signal altogether it's because that channel wasn't 20hz?

@JohnMGotts
When I was forced to move it to its new/current location.

 

[Ralston18]

Letting thread participants know the make and model router is not a security nor a privacy risk.

In fact someone may be aware of or otherwise be able comment about some known issue with that make and model router.

Four things that do matter: your public IP address, router admin/user name, router password, and perhaps the mac. Do not reveal that information.

And if the router is reset immediately change the default login and password.

I have a Linksys WRT AC1900, using 192.168.1.1 for my private home network.

Just like thousands of other small networks.