Background – As a recent Sky Digital subscriber I had a burning requirement to “deploy” Sky to the master bedroom. Also, I needed a solution that would work with all the other wireless technology already installed in my house (more on this later) and probably most importantly SWMBO doesn’t like the idea of more holes in walls.
Overview – You can use these devices to wirelessly transmit Video about the place and also allow remote control of the Video device from the receiving location via an Infrared repeater. Video Senders are nothing new and have been around for several years. I’m told the early models were a) “illegal” due to the unofficial usage of the 2.4Ghz frequency and b) not the best quality. Well, the EU being the wonderful thing it is has now agreed on something and legalised the usage of the 2.4 Ghz frequency. Other brands of sender exist such as GigaVideo, Thompson etc but I decided to go for the DigiSender due to favourable comments it was receiving from various USENET groups. Furthermore, although the DigiSender name gives you the impression it’s sole purpose is to transmit the contents of your Sky Digibox, you can also use it to transmit any SCART based signal, such as a VCR, DVD, OnDigital, CCTV or whatever you so desire! The infrared repeater re-transmits any IR signal so regardless of your device you should be covered. The only incompatibility occurs if you are using a specific Telewest or NTL cable box which use a completely proprietary set of IR codes. The current DigiSender can’t cope with these. However don’t panic as AEI Security is planning to release a specific version of the DigiSender for this purpose in the near future.
Installation – In a word, straightforward. The DigiSender is clearly aimed at the mass market and I managed to successfully install the device in less than 10 minutes. The only pain was fumbling around in the mess of wires behind my TV! The package is made up of a transmitter and receiver pair. First off, installation of the transmitter. You simply plug the SCART pass through cable of the DigiSender into the TV Out of your satellite box and then position the “Magic Eye” Infrared sender in range of your Video device. In my experience, exact placement of the “Magic Eye” is not required for successful use. I positioned the eye about 10 centimetres directly above the Sky Digibox IR sensor and it works fine. Rather than placing the transmitter unit directly on top of the TV I thought I’d go for the discreet option and try it in one of the free slots of my TV unit, which is located directly under the TV. To my surprise it worked straight off! Installation of the receiver unit was even less hassle. I just plugged the receiver into the SCART socket of the TV, placed the box on top of my TV and that was that. Incidentally, I purchased an additional Sky remote control for the master bedroom. You can buy these mail order directly from Sky or alternatively from Maplin, priced £19.99. If your TV requires an old school coaxial cable input you will need to purchase a separate UHF modulator, priced £24.99. This is available direct from AEI security, see the URL above.
The DigiSender allows you to choose between 1 to 4 different channels for Video transmission. This is useful where your neighbours may be using DigiSender and you want to avoid a conflict. Or like me you are concerned it may interfere with other wireless equipment using the same frequency. You select the channel you require on both the transmitter and receiver via 4 dip switches located on the rear of the units. I choose channel 4 to avoid any potential conflict with my wireless LAN (see details later in the review). Power to the units is provided via a 9 volt supply, simply switch on and the display on the front of the transmitter and receiver displays the transmission channel you have selected. So you there you have it, installation was very straightforward and the instruction manual was simple to follow. So, how does it perform?
Usage Let me say straight off the bat that I have not used any brand of Video senders before so I can’t comment on other systems. What I can say based on my usage of the DigiSender to date is that I have been very impressed with the performance of the system. According to the instructions the units have an effective range of 100M free air space and 25M in-building. I have tested various distances between the transmitter and receiver pair from about 5 metres to 20 metres. The quality is as good as watching on a directly fed TV. The remote control forwarding works flawlessly with my Pace Sky Digibox. Not much else to say, it works as advertised. Adding a second remote TV to the system should also be straight forward. AEI Security will sell you a second receiver unit for £49.99 from their web site. AEI claim there is no limit to the number of additional receivers you could add, making it easy to expand the system.
Compatibility with other wireless systems – As a keen HA’er I have a number of other wireless systems about the house, all using the same basic 2.4Ghz frequency. As you can imagine, I thought I might hit problems with the devices all using that same part of the radio spectrum. In addition to the DigiSender I have two other 2.4Ghz wireless systems, these are a pair of DECT cordless phones and a wireless LAN. The digital cordless phones are part of the Phillips Onis range and are designed to use slight offsets of the 2.4Ghz frequency to avoid conflicts with neighbouring phone users. The wireless LAN is made by Lucent, part of their Orinoco product range, I have a residential gateway and a “Silver” network card. I can configure the residential gateway to use one of four channels, in a similar fashion to the DigiSender. I decided to set the gateway to channel 1 and the DigiSender to channel 4. My logic being that this would provide the biggest gap in frequency usage between the two systems. So the moment of truth, did it work?
As the ultimate test I had Sky running remotely upstairs whilst I was using the wireless ePod in same room whilst making a phone call. To my initial surprise it all worked with no device interfering with any other! Clearly all the devices are using offsets within the basic 2.4Ghz band, all happily coexisting together. The only picture interference I noticed was when I had the receiving TV about 2 metres from the wireless gateway. This is not an issue for me as I don’t plan to have a TV in this part of the house. I also have several X10 wireless switch units such as the HR10 and the SS13 about the house which use the 433Mhz frequency. The DigiSender Infrared repeater also uses the 433Mhz band, 433.92Mhz to be exact. I have yet to experience any clashes. Again I suspect the slight offset in frequency usage is preventing any problems.
Conclusion – As you can see, everything worked out of the box, a refreshing change in my experience. Cost wise you could achieve the same result using a Sky TVLINK device and some cable for less cash but the major bonus for me is the fact that you have no need to drill holes and you can be up and running in minutes. I am a firm believer in these new wireless systems from a convenience and flexibility point of view. The only problem with this type of system is that you all have to want to watch the same thing!