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I’ve just splashed out nearly two grand on a Toshiba 36ZP18P surround sound TV, and although I have connected my SKY box to it using SCART leads the set appears to be receiving a mono sound signal. I have checked the settings within the SKY box and ‘Stereo’ sound has been selected. However, the green light on the front of the set remains unlit and the TV’s sound quality is much better when using an analogue signal. Is there a reason for this, and can something be done to rectify this situation. Sky is always promoting its ‘super surround’ are SKY ripping me off?

Stewart Eade, email



SKY isn’t pulling a fast one; the indicator light on the front of your TV simply shows that it is receiving a NICAM stereo broadcast, so it only comes on when you are watching one of the analogue terrestrial channels. There could be several reasons why the sound from the SKY box is less than satisfactory, the most likely one being that the TV’s stereo speakers are configured to work as a mono centre channel, there’s a small switch next to the speaker terminals and this should be in the ‘INT’ (internal) position. When we reviewed the set back in the December 2001 issue we mentioned that the on-board speakers are a little lightweight and the sub does tend to overwhelm the others so the surround effect can be swamped. You may need to tweak the settings so go back into the sound menu and try again. The other alternative is a cabling fault, try swapping or substituting the SCART leads, and if you have an AV amp or an old stereo amplifier handy it’s worth connecting the stereo output from the SKY box to it, to make sure that both channels are working.



A lot of widescreen surround TVs these days have the facility to use the stereo speakers in centre channel mode, which cuts out the need for a separate centre speaker that can sometimes be difficult to place. It’s a useful facility and well worth using since the speakers are ideally placed, either side of the screen, to produce a well focused centre channel, which in most cases is used for dialogue, moreover they should have a sufficiently wide frequency response to handle both analogue Dolby Surround as well as Dolby Digital and dts.




I have a Panasonic DVD L10 portable DVD player and I recently lost the battery for it. The trouble is Panasonic, having discontinued the L10, no longer produce the particular battery. After much phoning and emailing, I finally managed to get a vague outline of what the battery’s spec should be, and although I am willing to make a new battery, I’d rather purchase a new one. We all know that batteries eventually die, so I’m slightly bemused that Panasonic hasn’t kept some spares. Does anyone produce replacement batteries that will work with this product?

Rob Black



Although the L10 is no longer current Panasonic, like all manufacturers of consumer electronics equipment, is under an obligation to maintain stocks of spare parts for up to five years after the product has been discontinued. Replacement battery packs for the L10 are still available, but you might want to sit down before you read on. It may have to be specially ordered and this can take up to 28 days, and it will set you back £89.25, but you’ll be relieved to know that does include VAT and postage and packing. If you still want one then contact Panasonic’s parts supplier SCME Ltd on 0870 2417244. The only other option is to have the battery pack ‘re-celled’. There are several specialist companies that do this kind of work; try DSM Technology on 01942 272730, who should be able to give you a quote, though don’t expect it to be significantly cheaper than a new one…



In theory any re-chargeable battery pack can be re-celled, which is worth knowing if your device is more than five years old, or the company making it has gone out of business. However it’s not something you should try yourself, even though replacement cells are readily available. Apart from anything else you probably won’t be able to get the pack open without breaking it because the case is usually welded together, and it is vitally important that the correct safety devices (fuses and thermal cut-outs etc.) are installed as incorrectly wired cells, or the wrong types can explode during charging!





I have my Mordaunt Short MS 208’s main speakers bi-amped with four Cambridge Audio P500 power amps and an MS 905 centre speaker but there is now a lack of life from the MS308 sub. Some people say that by bi-amping the mains it will now need a bigger sub as the mains are now out powering the sub, could this be right if so what sub can you recommend? I have it set on my amp to sub only and have tried different set ups but it doesn’t change anything

Steve Gibbs



There is a bit of an art to bi-amping and it can be difficult to achieve a good balance of sound, especially with the bass on meaty speakers like your 208s, especially when used in a surround sound setup. That’s because you are encouraging the main speakers to handle more low frequencies (see Getting Started), and this will tend to sideline the sub-woofer. However by increasing the size or power of your sub-woofer you could be chasing a moving target and may, perversely, make it even more difficult to manage the bass. In general bi-amping is better suited to straightforward stereo sound – and this is something the 208’s do very well -- so you may want to go back and rethink your system.  If it is mainly going to be used for surround sound then you might be better off using a conventional AV amplifier, teamed up with some home cinema-friendly MS 302’s, and save those 208’s and the power amps for listening to music.




I have almost all of the high-quality leads I need to link-up my home cinema system, however, I have a problem. I’ve recently purchased a Samsung plasma TV, but it only comes with a two-metre, 24 pin, male-to-male DVI lead to connect the receiver box up to the screen. Considering that I keep all of my kit in a cupboard, I actually require a four or five-metre lead. Can you tell me where I can buy a longer cable?

David Harrison



As if we didn’t have enough plugs and sockets to worry about… With plasma screens comes a whole new opportunity for manufacturers to bamboozle us with unfamiliar connectors, and the bad news is there are no standards for the external tuner/connector boxes sold with some plasma panel. Some companies use their own proprietary connectors whilst a few, like Samsung are using DVI (digital video interface) leads. These were originally developed for the latest generation of digital computer monitors, but there are at least four different types; it makes SCART look simple...


Efforts are underway to encourage plasma TV manufacturers to adopt DVI-P but it appears that it may have insufficient capacity for some plasma panel/tuner box combinations, Hitachi has had to tack on an extra cable on to the DVI cable it supplies with its latest plasma TVs. As for your lead, we suspect it’s a DVI-I Dual-Link type but Samsung UK were only able to tell us that they didn’t supply longer leads or extension cables. The simplest solution is to go to the Pacific Cable website, (http://www.pacificcable.com/dvi.htm), where you’ll find the full range of DVI cables (with pictures and diagrams), so you can identify the correct type and order one from them direct, or try a UK supplier like http://www.homestead.co.uk/beldvi.htm.








When it comes to buying a plasma screen TV, in addition to screen size and extra features, you might also want to think about whether or not it comes with an external tuner box. Some dealers and manufacturers regard them as optional extras, in which case you should check the price. Having an analogue TV tuner built into the panel is only useful if you watch a lot of terrestrial TV, otherwise it’s better to get your TV channels via a digital source (satellite or FreeView) so you get the benefit of widescreen formatting.  




I want to be able to listen to music in my kitchen/conservatory and garden, so I’m looking to purchase speakers that can run off the mains. I don’t want to add more cables to my Mission system. But, despite looking around, I can’t find this kind of product at all. Does such a product exist that is of decent enough quality, reasonable price, etc?

Mr Rowles



It depends what you mean by ‘decent quality’. Since you are unwilling or unable to run cables the only other option is a wireless system. Inevitably there will be some degradation as the sound from your amplifier has to be converted to and from a radio frequency signal, but there’s a fair selection of products on the market of varying capabilities and most of them are either mains powered, or can be run from a mains adaptor. There are two types: speakers with a built-in amplifier and receiver or a ‘sender’ type device, which relays the signal from your amplifier to headphones or another amplifier and speakers in the conservatory. They operate on three ‘licence exempt’ frequency bands, which roughly equate to quality; at the budget end of the market there are systems costing from under £50 that use the 433MHz band; mid range/quality devices use 863MHz and at the top end there are AV senders (just use the audio channels), costing from £100 upwards that operate on the 2.4GHz band. You’ll find a range of systems that you can buy online at: http://www.threedoubleyou.com/cordless.htm



Under current UK regulations licence exempt wireless or ‘cordless’ AV equipment is only allowed to use analogue FM signal encoding. That basically means they suffer from to relatively high levels of noise – they can be quite ‘hissy’. The other point to bear in mind is that the power output from the transmitter is quite low and they can only operate on a limited number of channels so there is the possibility of interference from other nearby systems and devices like cordless telephones. In practice interference is rarely a problem, though, as the range is usually less than 100 metres.




I am considering buying a plasma TV, however, my daughter watches three to four hours of Sky’s Boomerang Cartoon channel every night. As you may know, Boomerang has a permanent bright blue channel logo on the top right-hand corner of the screen. In your opinion, could this cause screen burn on a plasma TV?

Behrooz Lessani



Screen burn, caused by on-screen logos and station idents (known in the trade as DOGs or digitally originated graphics), prematurely ageing the phosphor dots or pixels on the inside of the screen is not as much of a problem with plasma panels as it is with CRT displays. Nevertheless it can and does happen. Fortunately the condition has been known about since the earliest days, when a lot of first generation panels were used for public displays, in shops and airports etc. showing static text or graphics for prolonged periods. Manufacturers have developed a number of strategies to counter the problem, from screensavers, which blank out the display and show a moving graphic, to pixel shift or screen ‘orbiters’, which moves the image by a few pixels every so often. Several screens also have a ‘whitewash’ facility, which floods the screen with a bright white picture that is supposed to refresh the pixels. We have also come across panels that have a dedicated text or graphics display mode that automatically lowers brightness and contrast levels for static displays. In short it’s not something you need to worry about, though as for your daughter’s viewing habits…



The chances of suffering screen burn from permanent channel idents or DOGs is actually quite small as the intensity of the graphic is carefully controlled. Channel 5 was forced to reduce the brightness of its logo, and Channel 4 removed theirs after a brief trial following protests from viewers. Unfortunately this kind of blatant branding is probably here to stay on the satellite channels. Broadcasters claim it helps viewers find their way around in a multi-channel environment, conveniently ignoring the fact that satellite viewers can display channel name and programme title at the touch of button. 




After reading your review on the One for All Kameleon universal remote control (HE111, Dec 2002), I’m interested in investing in the technology. Do you know where I can buy infrared switches for my house, if you can get any at all? I want to use an infrared remote control to program home cinema kit and lights, etc.

Hyder Khan



It can certainly be done but as yet there’s no such thing as a simple, or cheap, off-the shelf solution. The problem is that there are no universal standards for AV remote control and every manufacturer uses their own protocols and codes. That can be overcome to some extent with programmable and learning remote control systems like the Kameleon and its more sophisticated brethren but then you come up against the problem of devices and appliances that do not have a built-in remote control facility. Again there are ways and means and a number of ‘home automation’ systems have appeared (and often disappear soon afterwards) but there’s still a lack of standards. The closest yet is a modular system, developed in the US, which goes under the banner ‘X10’ (see Getting Started). If you’re seriously interested in the wired home concept then be prepared to pay big bucks for a custom installation – several companies advertise in the back of HE -- or wait a couple of years for a promised flood of wireless products and home networking gadgets.



If you’re going for a universal remote control (URC), think big! Tot up the number of remotely controllable devices in your AV system. You’ll probably be surprised how many there are, if it’s fewer than five or six you’re either leading a charmed life and you have a highly integrated or predominantly one-make system, or it’s not up to much! You will need a URC that can control at least 10 devices, and preferably more, like the One For All Mosaic which has 15 function sets and a backlit LCD touch screen  




I’ve just bought a Panasonic 42PWD5 plasma screen with BNC sockets for the video inputs, a Yamaha RX-V730RDS receiver, Yamaha DVD recorder/player, and a KEF KHT2005 speaker system. I also have a cable set-top box, which I also need to hook up to the system. My main question is how do I connect up the set-top box and the plasma screen to the tuner? Also, which connection will carry the picture to the plasma? Please note I have S-type connections along with several BNC sockets. I thought connecting up all of these products would be simple, but to my surprise I don’t really understand the technology’s lingo – RGB, coaxial, etc.

Bill Billing



It’s never too late to learn the jargon though next time it might be a good idea to do a bit of homework, before you’re surrounded by piles of boxes and lots of cables… The dealers who sell these products are usually only too happy to oblige with advice. It sounds as though you have a plasma display fitted with a video card, and the optional tuner box, in which case you need to connect it to the panel using composite, S-Video and RGB connections so it can act as a switching centre for all of your external inputs. In the case of the BNC connections for the RGB input you can use phono-to-phono leads with BNC adaptors. Your cable box can connect to the tuner box using a SCART to SCART lead. Assuming your DVD player is a UK spec model you should connect that to the tuner box using a ‘fully wired’ SCART to SCART lead; make sure the player is set for RGB video output on its setup menu. If it’s an imported all-region model with phono sockets on the back marked Pb (Cb), Pr (CR), Y, you can connect it directly to the panel’s Component video inputs using a set of phono-to-phono leads and BNC adaptors.





Bi-amping is an advanced technique favoured by audiophiles whereby separate amplifiers, or separate channels on the same amplifier, are used to carry the high and low frequency outputs to the same loudspeaker. The idea is that by separating the two sets of frequencies you can use a more powerful amplifier for the bass channels, and a lower power but better quality amp for the treble and mid-range frequencies. Additionally, since this type of arrangement requires the use of a pre-amplifier you will have much greater control over the sound output. This type of setup also gets around the need for low-pass crossover filter networks and corrective circuitry in the speakers, which because of their electrical characteristics can cause problems with mis-matching when speakers of different sensitivities are driven by a single amplifier.


Incidentally, not all speakers can be bi-amped but the ones that can are easy to spot because they normally have three drivers (tweeter, mid-range and woofer) and on the back there will be two sets of terminals or binding posts. For normal (i.e. non bi-amped operation) they are connected together with metal strips. Usually the top two terminals are for the tweeter and mid-range drivers, and the lower pair is for the woofer or low-frequency driver. 


In an AV surround sound system the bass content from sources like DVD and video soundtracks is usually a lot greater, and used to generate gut-rumbling effects whereas on a normal stereo hi-fi setup, used for listening to music, bass frequencies are at a much lower intensity and tend to be used more sparingly. For this reason in a home cinema system it is better to handle the bass frequencies separately using a powerful sub woofer.




Consumer electronics companies around the world have been playing with the idea of the wired and fully automated home for decades but apart from the fortunate few, with deep enough pockets to pay for a bespoke installation, it has remained tantalisingly out of reach.  It’s no coincidence that many of the most successful home automation projects are installed in newly-built homes, where the miles of wiring and problems with the complex control systems can be solved at the design stage and fitted into the fabric of the building with a minimum of disruption.


The first serious attempts at developing a home ‘bus’ or network were back in the 1980s when companies like Philips, Sony and Panasonic came up with the Domestic Digital Bus (D2B),  Home Bus System (HBS), Espirit and CEBus. One by one they have disappeared due to lack of cross brand support, though parts of some of these systems live on in the form of features like NexTViewLink and AVLink, whereby TVs and VCRs can communicate with one another.


The most popular home automation system to date is X10, which gets around the need for a wired network by using household mains wiring to carry control signals. Instead of individual products having a standard control interface they can be switched on and off using plug-in mains adaptors, and individual functions may be controlled using infra-red command codes, transmitted and received from wall mounted modules. The system can be easily expanded by adding extra modules and it has become moderately successful (in the US at least) encouraging other manufacturers to develop compatible products. X10 systems are now available in the UK, for more info have a look at: http://www.letsautomate.com/.



Ó R. Maybury 2003, 0703



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