There are a number of things that can affect a Wi-Fi signal, from physical obstructions to technical settings on your router.
If your signal is always slow, it might be the router's location causing problems. Brick walls, concrete, metal and mirrors all affect your connection, so start with repositioning your router.
First of all, make sure that your wireless router is positioned high up and in a clear space — for example, on top of your desk rather than under it — to maximise your chances of a strong signal. It's a good idea to ensure that there aren't too many solid objects in the way, too.
Other wireless devices also cause interference. Generally speaking, anything that's cordless or wireless, like baby monitors or phones, can create an issue. Electrical equipment, even microwaves or other kitchen appliances, can also cause problems, too.
On the whole, it's best to keep your router on its own somewhere. It won't cause huge problems if it's within a couple of metres of something electronic, but if it sits on top of a speaker or your computer tower and your signal's dropping in and out, now is a good time to move it.
More advanced tips
By accessing your router's configuration page, you can change details like the name of your network, the channel it broadcasts on, and the password. If you search the make and model of your router online, you can find out exactly how to do this.
Once you've got the configuration page loaded, follow these tips to boost your Wi-Fi's performance:
Changing channel: Typically the channels run from one to 13 and, by default, the channel is set to auto. In theory, this will select the strongest channel for you, but it's often best to set this manually. In the UK, the most commonly used channels are one, six and 11, so it may be worth trying something else.
Security: Sometimes the signal strength is low because someone's stealing your internet! Make sure you use at least WPA2 security; WEP isn't very good at all and is very easy to hack.
Upgrade equipment: Although network cards and routers all work together, it's best to match the broadcast type and, if possible, the manufacturer. The broadcast type will be A, B, G or N. This simply refers to the strength and distance of the signal. If you're not getting enough, upgrading to N may help.
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