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SATELLITE HOOK UPS
INTRO
Confused by cables, perplexed by plugs? Rick
Maybury helps you make the right connections
COPY
The 72,000 kilometre round-trip, taken by
satellite TV signals to get to the dish outside your home, is the easy bit!
That journey only involves several hundred million pounds worth of equipment
and the efforts of countless highly trained engineers but turning those signals
into decent quality pictures and sound is another matter. Far too many people
end up watching sub-standard pictures but with a little care satellite TV can look
and sound every bit as good as terrestrial TV, and a whole lot better than VHS
tape.
Clearly the first consideration is the dish
and receiver. Nowadays there’s not a lot to choose between the majority of
mid-market systems, indeed most of them are manufactured by just a handful of
companies, and there’s even less diversity in critical components, like LNBs
and tuner modules. However, the starting point has to be a receiver with a
stereo sound system, preferably with Wegner-Panda I noise reduction. Proprietary
noise reduction systems are improving, and one or two are almost as good as
Panda, but the cost differential is now so small that it’s not worth trying to
save a few bob by buying a non-Panda receiver. Even if you’re using top-notch
equipment, AV quality can still suffer if the dish isn’t properly installed,
the wrong size, or the downlead isn’t up to the job, so before you go any further
make sure the system is giving its best.
The connection between the satellite receiver
and the TV is where most damage can be done to the sound and picture. The
simplest method is to route the STV receiver’s RF output via the TV aerial lead.
This type of hook-up has one obvious disadvantage, the pristine video and audio
signals produced by the receiver have to go through several additional
processing stages, which introduces extra noise into the signal; furthermore,
the audio output, which started out in stereo, ends up in boring mono by the
time it emerges from the TV’s loudspeakers, even if it is a stereo set. Worse still is the temptation to route the RF
signals from the sat receiver through a VCR, so satellite channels can be
recorded. This entails a lot of messing around with the VCR and TV tuners, and
more often than not, adjusting the RF modulators in the satellite receiver
and/or the VCR to avoid co-channel interference. This also adds to the noise problem, and you still end up with
mono sound.
The ideal solution is to use the multi-pin
SCART AV sockets on the backs of the satellite receiver, VCR and TV, assuming
of course your equipment has been made within the last six or seven years. If
your TV or VCR doesn’t have SCART sockets then they’re so old that it’s about
time you replaced them! Using AV connections to link AV equipment ensures the best
picture and sound quality as the signals undergo minimum re-processing, but
what if you haven’t got a stereo TV? No problem, virtually every stereo satellite
receiver and VCR has separate line-audio outputs, normally in the form of a
pair of phono sockets. They are for connecting the stereo outputs to a hi-fi
system. In most cases the results are a
lot better than you would get from a stereo TV. That’s because hi-fi speakers
-- even those supplied with budget systems -- are a whole lot better than the
titchy little squeakers used in most stereo TVs, moreover the enclosures will be
more bass-friendly, and they can be placed either side of the screen, to give you
more control over the sound-field.
Better still, use the line audio outputs to
connect the satellite receiver and stereo VCRs to an AV amplifier or system, with
a Dolby Pro-Logic (DPL) decoder, to create a home cinema system, so you can enjoy
the amazing multi-channel surround sound effects that are hidden inside the
stereo soundtracks of most recent movies and a growing number of TV programmes shown
on satellite TV, and on rental movies on tape.
There are two alternatives worth thinking
about: TVs and satellite receivers with built-in Dolby Pro-Logic processors.
There’s now a good selection of DPL TVs, Toshiba were the first TV manufacturer
to offer this facility, and they still have the largest share of the market,
but there’s now a growing number of sets from other manufacturers, including
Hitachi, Ferguson, Nokia, JVC and Sony. The disadvantages are cost -- the
cheapest surround sound TVs start at £800, you might not want to replace your existing
set, and remember, most of these sets have small speakers and/or relatively low-powered
amps. DPL satellite receivers are still a little thin on the ground, with models
available from Pace (also cloned by Hitachi), and Amstrad. They can give quite
good results but again power levels are generally lower than those from AV amps
or systems. In their favour both TVs and DPL sat receivers are easy to install,
and involve fewer boxes than a component system, though a there’s a lot of new
mini and midi AV package systems coming onto the market. They can be quite
reasonably priced too, the cheapest one, (Sony MHC-901AV) costs less than £500,
though the majority of them sell for between £650 to £1000.
Whatever type of system you end up with you
will be faced with a bewildering assortment of plugs and sockets. If you opt
for a package system interconnections between the various related components
will be taken care of, using the supplied leads, but there remains the problem
of connecting external devices, and you will almost certainly end up having to
buy one or more cable sets.
The obvious point about getting what you pay
for holds true, but so too does the law of diminishing returns and an AV lead
costing £5.00 can perform every bit as well as one costing £10 or £20. So what
should you look for? Needless to say you should make sure it’s the right type,
and the correct length. There’s no simple way of checking manufacturing
quality, other than by taking it apart, but you can limit the chances of ending
up with a lemon by only buying from a reputable dealer, and preferably sticking
to the better known brands (see contact listing).
Should you go for gold? Leads with gold
plated connections are all the rage, but are they worth the extra? Gold is used
for two reasons, it’s an excellent electrical connector, and it doesn’t
tarnish. That’s important as when plugs and sockets are pulled apart the
contacts come into contact with sweaty fingers, moisture in the air and
atmospheric contaminants, which can lead to corrosion and oxidisation, both of
which can result in poor electrical contact, and that creates noise. If you reckon
on doing a lot of plugging and unplugging it’s worth paying a little more for
gold plating, but don go overboard, it should only add between 15 to 20% to the
price.
BOX COPY 1
GET CONNECTED
THE BETTER SATELLITE GUIDE TO PLUGS AND
SOCKETS
Belling & Lee/Coaxial/RF
Familiar push-fit plugs and sockets, used to
carry UHF and VHF signals from the aerial, to the TV. Coaxial connectors were
also used for dish antenna connections on a handful of early satellite TV
receivers
F-Connector
F-Connectors are normally found at both ends of
the cable or ‘downlead’ linking the LNB on a satellite antenna with the receiver.
The threaded metal collars that hold them in place reduce loss, prevent
interference, help to make them weatherproof and keep them securely in place.
Phono/RCA/Cinch
Simple push-fit plug and sockets, used to
carry audio and composite video signals. Black, red or sometimes white coloured
plugs are used for audio, and yellow for video.
SCART/PERITEL/Euroconnector
21-pin plug and socket system used for AV,
data and control signals. Several configurations are available, the most
appropriate ones for satellite and home cinema are Type ‘C’, (9-pins wired for
composite video and stereo audio), and Type ‘U’, (all pins wired). Make sure the
AV connections are ‘crossed’, so that inputs are correctly wired to their
corresponding outputs.
S-Video
Also known as a Y/C or mini DIN connector. A small,
round push-fit 4-pin connector, used to carry specially formatted video signals
between TVs/ video projectors and video components such as Super VHS (S-VHS-C) and
Hi8 VCRs and camcorders
Telefunken Plug
Yes, even those plastic/rubber mains plugs on
the backs of VCRs and satellite receivers have a name.
BOX COPY 2.
SOLDERING ON...
AV cables can be expensive and yes, you can
save money by making up your own custom leads, moreover it’s a good way of
ensuring they’re the right length. Plugs and sockets of all types, and
multi-way cables are readily available from Tandy, or specialist electronic
suppliers like Maplin, but you need to be adept at soldering. The terminal pins
on plugs and sockets are very close together, and the plastic insulation on
most leads softens and melts quickly. You need at least two pairs of hands, or
a jig to hold the parts in place. In short there’s enormous scope for error,
and considerable potential for damage to equipment, if connections are
short-circuited, or wrongly wired, so unless you are an accomplished solderer,
forget it!
BOX COPY 3
USEFUL CONTACTS
Lead manufacturers & suppliers
AICO INTERNATIONAL, Aico House, Faraday Rd,
London Road Ind Est,
Newbury, Berks RG13 2AD. Telephone (01635) 49797
BANDRIDGE LTD, Premiere House, 18 Deer Park
Road, Wimbledon,
London SW1 3TU. Telephone 0181-543 3633
BIB AUDIO VIDEO PRODUCTS, Kelsey House, Wood
Lane End, Hemel Hempstead, Herts HP2 4RQ. Telephone (01442) 233233
HAMA Unit 4 Cherrywood, Chineham Business Park,
Basingstoke, Hants RG24 OWF. Telephone (01256) 708110
JOSTY LTD (LINXS), Perry Avenue, Teeside
Industrial Estate, Thornaby,
Cleveland TS17 9LN. Telephone (01642) 769000
LEKTROPACKS Windsor House, 141 Bath Road,
Houslow, Middlesex TW3 3BT
Telephone 0181-572 9737
VIVANCO, Unit C, ATA House, Boundary Way, Hemel Hempstead HP2 7SS.
Telephone (01442) 231616
PLUG AND SOCKET SUPPLIERS
MAPLIN ELECTRONICS, PO Box 3, Rayleigh, Essex
SS6 8LR.
Telephone (01702) 554000/554161
TANDY/RADIO SHACK, Tandy Centre, Leamore
Lane, West Midlands WS2 7PS
Telephone (0922) 710000
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Ó R. Maybury 1995 2505
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