Wi-Fi vs. Video Senders

02-12-2006

I want to be able to transmit the satellite signal from my SKY box to any other TV in my home so I was taking a look at the latest video sender units that are available on the market. It has been a few years since I purchased such a device and there have been many modifications over the years. I still have an old UT-66 black box lying around somewhere but that uses BNC and phono connectors and technology today tends to use SCART. The Wizard pyramid devices were recommended to me but I have yet to find any for sale.

Today’s video sender devices have form factors that resemble set-top boxes with aerials or baby monitors. Reading a few specs online I was impressed that not only can they transmit TV, video and satellite/cable but they can also transmit video played on your PC such as DivX to any TV in your home. They can even transmit mp3 music from your PC to any HiFi within range. Well, I was impressed until I read further. The latest generation of video sender devices transmit using the 2.4GHz frequency. Yep, they transmit using the same band as Wi-Fi. So before I rush out and buy one I needed to know if they will work alongside my home Wi-Fi network.

I went to Maplins and asked to see their video sender units. The assistant was very helpful and fetched the best seller from out back. It appears that other shoppers have had the same idea as me and these units are selling well. When he returned I could see that the box in his hands had “2.4Ghz” written on it so I asked if it would affect my home Wi-Fi network, at which point he took the box back and said “sorry these are not compatible with your Wi-Fi”. He said they affect home Wi-Fi reception so they don’t sell them to anyone that says they use Wi-Fi at home. I assume that this policy reduces the amount of returns they get.

When I returned home I scoured the net for any information on reports of these boxes affecting home Wi-Fi networks. I found several. I downloaded a few manuals and spec sheets for popular units sold through online sellers such as Amazon. Some of these units are actually Wi-Fi devices that utilise the 802.11b and 802.11g standards and come with 1-4 pre-set channels.

Ok so can they affect my Wi-Fi network? Apparently yes. Even if you set your AV sender to one channel and your Wi-Fi network to another some interference problems have been reported. Some people have resolved these issues by using the B standard on one and G on the other. That might solve the problem in your own home but what about your neighbours? Over the last year I’ve had to change the channel on my Wi-Fi router twice due to a neighbour with a more powerful broadcast signal using the same channel and knocking me off the air. As Wi-Fi gains in popularity and more homes set up their own home network using Wi-Fi equipment the available 11 channels will not be enough. Especially as new build houses are closer together than ever before allowing your Wi-Fi network to cover not just your own home but two or three others as well.

The 2.4GHz frequency is unlicensed and unregulated so we can probably expect more and more consumer devices to start using it. It is already an annoying that cordless phones, blue tooth devices and microwaves can affect your network, but add to the mix these AV media broadcast devices and it wont be long before it becomes very hard to operate a reliable home Wi-Fi network with little or no interference from nearby devices operating in the same frequency range.

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