Computer doesn't work well with the WiFi

The WiFi router is on a table in the corner of the living room, near the bottom of the stairs.

Smartphones can connect, stay connected and show a good signal strength, from anywhere in the house.

But the computer upstairs, which is quite a few years old but works fine, has been having problems for several months now. It's in a bedroom next to the top of the stairs.

Sometimes, it just doesn't want to connect at all for a long time. And when it does, the signal strength on the computer never goes above 2 out of 5 bars (but it does work fine even at this seemingly low signal strength). But then it may just randomly lose the connection to the Wi-Fi, and again, not want to connect for a long time.

Right now it seems stable, but this morning it wasn't connecting/staying connected for the majority of the time.

Any ideas?

What kind of WiFi adaptor does the upstairs computer have? Is it a desktop with a PCI Wifi card or is it a USB Wifi Dongle? The latter would be an easy/cheap thing to change to a different one to see if it makes a difference.

I've had issues with a USB device in the past which once changed to a different brand was fine ever since. The original temperamental device is one of the reasons why I will never touch another Belkin product again.

I looked behind the computer now to check and remembered it's a Wifi card.

I saw that the antenna itself was very loose, so I screwed it on properly. Signal strength immediately went to 3 out 5 bars.

But as it was very dusty I unscrewed it, cleaned it and screwed it back in again. But it then seemed to just fall off. I saw that the actual gold pin from inside the antenna was still connected to the computer. So I just screwed the antenna back on, around the stuck pin.

Signal strength now fluctuates between 3 and 4 bars. Hopefully, it should be ok now. Will see.

Why not ditch the Wifi, (if your computers old, its probably got slow wifi anyway, which means it slows down all the other devices on Wifi, if you have a router setting "Airtime Fairness" try it.

I would suggest you move your PC to Powerline, they actually work remarkably well (ignore the speeds quoted, its marketing hype of maximum link speed, you will get around 100Mbps + with 600 around up to 350Mbps on 1300, but for the price it will help out other users of your Wifi. (It uses your houses electric wiring to send data).

https://www.amazon.co.uk/TL-PA4010KIT-Powerline-Configuration-Required-UK/dp/B016ZZAVYI/ref=sr_1_1?ie=UTF8&qid=1526210754&sr=8-1&keywords=powerline%2Badapter&th=1

Could also replace the WiFi card for a more modern one - they are really cheap these days and it takes minutes to swap out. Another boost can be got buy using a bigger antenna.

just get one of these and be done with it

https://www.techadvisor.co.uk/test-centre/network-wifi/best-powerline-adapters-for-2018-3490638/

One question I always have about powerline units is where does the reach stop?
Same ring main
Same consumer unit
Same electricity meter

GCHQ

We actually have some of these powerline adapters to fill the gap between getting around to laying some LAN cables around the house. The main router is at ground level. One powerline pair feeds the cellar, another the attic. Non of these are on the same ring and are connected via the circuit breaker box. Any connection seems to work in our house so it must be anything connected to the same circuit breaker box???

However, the more complex the connection from the first powerline adapter, the weaker the signal gets. The attic and cellar seem to have about 40% - 50% of the internet connection speed that the main router shows with the TP-Link AV2000s.

As you have a fairly strong signal at the old pc, the simpler option would be a better wifi card with a good antenna. The Powerline option may be better but is more expensive, a little messier but would allow you more flexibility (e.g. can add a second wifi router to improve wifi coverage in your home).

Great feedback neil_r thanks

They don't need any physical connection between them at all as they actually use short wave radio to communicate.

It's been proved that they work perfectly at full speed when one is run from a generator without any physical connection to the mains. There are videos on youtube showing that + the huge radio interference they push out,

Wireless extenders could work like that for sure (repeaters)

But, powerline adaptors use the electrical wiring to communicate, so I have always assumed they would need to be on the same ring main

It was the powerline adapters I meant... they need no physical connection as they work by shortwave radio.

There's a video on youtube of a guy showing them working at full speed with one plugged into the mains in his house and the other one plugged into a generator in his back garden!

And he also shows the 2 powerline adapters on the same mains ring losing their connection to each other when he broadcasts shortwave radio to "jam" their communication.

Powerline adapters use the mains cables in the house to transmit the network signal, hence the name. They have nothing to do with radio signals.

Disrupting electronics is a completely different kettle of electrons.

From Mario's link:

"What are Powerline adaptors?

Powerline is a simple-to-install digital home technology ... for connecting devices to your network, regardless of whether or not they're in the same room as your router.

It uses your home's mains power wires to create a network connection ..."

That's what the marketing tells you, but there is proof otherwise if you take the time to look for it.

It's a conspiracy I tell you, it all comes back to GCHQ just like cyborg7 told us

More likely than the SW radio theory. Or maybe I should get that aluminium cap after all

Just stick your fingers in your ears and hum a tune whilst saying "I'm not listening"... I've not seen the SW radio videos, but they sound a bit like those home made videos of what happens then you put bricks inside a washing machine...

Ok I'll bite and see what is out there.

As one would expect, powerline adapters work over the power lines. Nothing fishy there. However, they might cause interference to SW radio waves so anyone nearby trying to communicate with SW radio may have problems:

"HomePlug adapters are often referred to as PLT (Power Line Telecommunication) devices, and shortwave radio enthusiasts claim that they can effectively turns your home into a low-powered transmitter, as your home’s mains cabling radiates a low-power “noise” in the band used by short wave radio (2Mhz to 30Mhz)."

No conspiracy on the technology front, just an undesirable side effect for some.

I've seen the videos a while ago but wasn't exactly convinced. I might try and dig them out as to be honest I didn't get to watch them all the way through due to the guy narrating being less than engaging in nature.
The main issues I had were that I would have liked to see better quantified tests especially with a network analyser so it could be seen how much power goes through the wires and how much out to the air. For me it shouldn't be a shock that putting relatively high speed signals down unshielded wires designed to carry 50Hz leads to
a) Elements of the wire behaving as an antenna at either end
b) The wires themselves being susceptible to noise

I'm still not a fan of the devices themselves as I think that electrically they are a messy solution (for reasons that can be derived from my comments above) but have used them as a necessary evil in my last couple of houses. Saying that however, I work from home 3 days a week and found that they drop out quite a lot when used for extended periods of time so last year bit the bullet and paid an electrician to run LAN cable round the house so I have wired network sockets instead now.

Edited to add
Fill yer boots
Uno
Dos
Tres

P.S. How far off topic have we managed to drag a thread that hadn't been posted on for over a month? This is just just like the old days.

Man I bet this dude has fight girls off with a stick when he pops down the local

Could it not be that your powerline adapter is capped at a certain throughput ? 10mb? 50mb? etc

I don't believe so as they get slower as they get "further away". If they were capped, for whatever reason, they would be equally slow everywhere. The adapters have a real bandwidth that should cope with our broadband speed but they don't get close as the routing becomes longer and more complex.

Powerline adapters are OK for non-critical applications but a hard-wired connection is always the way to go if at all possible. I just have not had the time to see if I can route them through the canals that are used to take the Sat. cables around the house. One day I will have time for everything I would like to do.

agree

Thirded.

I'm very glad I paid someone else to do the wires though as the mess that I'd have made getting wires from A to B would have ended up with a building site that would have taken me weeks to sort out. As it was, two electricians with the correct type of pokey stick thingies and experience in working out how to get from A to B efficiently did it in a day leaving some holes to patch that you would have barely known were there. They put the pattress boxes in and I just had to wire up the sockets.

It's always good to see the correct technical terms being used.

That's strange, it's almost like they're using low power radio signals to connect.

Graham I think we need you to take a powerline adaptor apart and see what's going on, is the earth connection really used as a network cable? How can one "wire" take the place of 4 twisted pairs? Do they transmit and receive SW radio signals, or do they just generate SW radio interference?

Did the moon landings really happen? Who shot JR? I could go on...

Lost on most ...

Damned if I know. Probably the early coax - single conductor - networking used wireless too.

Oh, wait. It didn't. And neither does Powerline.

Then how does it work perfectly when there is no physical connection between the 2 devices? Is that not the definition of "wireless" communication?

Maybe I should do a test? I have a UPS that I could plug a Powerline thingummy in to, with another on the mains, and I could wander around the house with the UPS / Powerline / and ethernet laptop...somewhat cumbersome however...

The only slight flaw with that method is that would just be the same in principle as that shown in the video. In other words, not proof. Without a network analyser in the loop I don't see anything other than interference causing trouble with a susceptible system and cross-talk (forgive the slight bending of the dictionary definition) serving an unintended purpose.

Mind you, now that I've actually watched those videos, if the powerline adaptors wind up short wave radio enthusiasts that much I'm going to start buying loads and plugging them in everywhere.

How would you use a network analyser to work out what's going on? I don't have the faintest idea how to use one...

As this is way more interesting than the work I'm supposed to be doing this morning I'll give it a shot at explaining what I mean.

Couple of bits of reading material, this on network analysers themselves and this on s-parameters but read the next paragraph before diving into them.

Ignoring that the presentation in the first link is 135 slides long ( :o), the first 4 slides explain the general purpose of a network analyser and the diagram in slide 5 shows exactly what I would like to see measured. This is normally in terms of s-parameters of which there is some explanation on slides 27~29 and in the other link. The other 127 slides are not necessary for the purposes of this discussion.

Starting with slide 5, in particular the diagram with incident, reflected and transmitted waves, what the videos are showing are the reflected waves bouncing out into the air. This can be measured with a spectrum analyser as shown in the videos but, without knowing how much power is transmitted in the first place (incident wave) or how much is coming out the other end of the mains wire (transmitted wave), there is no context and it doesn't tell me anything other than the fact that some power is lost to the air. This is the main crux to my scepticism of the videos as it comes as no shock to me that pumping relatively high frequency signals down an unshielded cable designed to carry 50Hz results in lots of reflected waves large enough to be measured in the air with a spectrum analyser. This is also a reason why I don't like powerline adaptors.

Where a network analyser comes in is that it can measure the reflected and incident waves giving the ratio of power lost over power sent. This is the S11 parameter. The other thing that could be measured is the ratio of power received over power sent (this is the S21 parameter). It does this by sweeping frequencies into whatever is being measured and is capable of measuring the reflections back into the device itself as well as transmitted waves if the other end is also connected (it wouldn't have to be as, putting it simplistically, we are just looking at incident = transmitted + reflected so either measure would do).

The easiest way that I see this being set up is by first measuring whatever frequency the powerline device is transmitting (a spectrum analyser or network analyser could do this) and then mimicking these frequencies with a network analyser connected to some mains cable. That would give a proper measure and cynical me suggests that the ratio going through the wire would be the lions share.

I can't be arsed to watch those videos again but IIRC the frequency coming out into the air was centered at around 100HMz which will be able to transmit either significant distance (relative to higher frequencies such as 2.4 or 5GHz) or alternatively a short distance with relatively little power which is what I suspect is going on here. The fact the that video shows an inverter powering one of them down the garden is of no relevance as the mains wire ends are still both in the same room. The invertor could be in Timbuktoo and I would still expect the same result.

Of course I could still completely wrong as what I would like to see measured hasn't been yet so I'm still open to a proper proof.

Now that I've seen how long my reply is you may regret asking that but hopefully not.

Yes, I think I do regret asking, and I should be working on my day job...

I will read in detail later, but please confirm that you meant to say

I did indeed, now corrected.

Well to do a test it seems like I would need some expensive gadget, it's not just a case or running some fancy software?

What it seems to boil down to is that yes, the earth conductor is used to send and receive network signals, but an undesired side-effect is to generate SW radiation which it just so happens can be received by an isolated powerline adaptor and turned back into network signals?

They certainly aren't cheap bits of kit. The inner workings of these things are way beyond my comprehension but I am understood to believe that the main bit of trickery needed is being able to read the reflected waves back on the same port so I'm not sure if there's a fancy software way round this. I've been out of the industry a few years now though.



Yep. this is pretty much the crux of what I think is happening.