[Our cover story in the July 2011 issue of PC & Tech Authority magazine is a must-read for Wi-Fi users. Below is an excerpt, with some of the things that can get in your Wi-Fi's way. Get the magazine for the full list, plus more tips and tricks for fixing wi-Fi problems.]
[Update: We've now published the full list here.]
Analogue video senders
Video senders – typically used to beam satellite/cable pictures to another TV in the house – are commonly regarded as public enemy number one when it comes to Wi-Fi interference. Everyone, from carriers through to router manufacturers, points their finger at the senders and similar devices, such as baby monitors and wireless security cameras. “Analogue video senders have a different spectrum profile to Wi-Fi, to the point where they obliterate Wi-Fi. You can’t even see an SSID,” said BT’s Adrian Pote. Since the signal is always on, even when no video is being sent, video senders are often hard to diagnose as a source of interference, and their reach is wide enough to hurt neighbours’ wireless too.
Microwave ovens were the very first household electronic devices to emit interference in the 2.4GHz band, so wait until the movie has downloaded before cooking your microwave popcorn. Research from the Farpoint Group suggests that data throughput can fall by 64% within 25ft of a microwave, and Farpoint analyst Craig Mathias said the firm had even “seen problems at 50m”. Unlike video senders, microwave interference should only occur when the oven is in use.
Wireless speakers and console controllers
Wireless speakers, console controllers and music players: it might seem like the living room of the future, but those devices can all interfere with Wi-Fi. “A major issue is any device can operate in the unlicensed band [used by Wi-Fi],” said Mathias. “There are a lot of devices in that band.” Cordless phones shouldn’t interfere with your Wi-Fi (unless you’ve bought them from abroad), as they don’t operate in the 2.4GHz band.