TVFM Guide
BROADCAST RECEPTION
& TELECOMS GUIDE
ANALOGUE - DIGITAL - TELEVISION - RADIO
SATELLITE - CABLE - SIGNAL AMPLIFICATION
& DISTRIBUTION - AUDIO/VIDEO
INDEX
The first section of this Broadcast,
Reception and Telecom Guide has
been written to help you
understand the basics of Terrestrial
Television, Radio, Satellite and
Cable Broadcasting considering
both analogue and digital formats.
The second section considers
reception issues in more detail
looking at the different products
available in the market and
guidelines to successful installation
of DIY projects. The third section
looks at Telecoms including
telephone, fax and modem. This is
a very fast moving industry and
information will quickly become
out of date and be superseded.
If you would like any further
information please do not hesitate
to contact Maxview on the
following:
Customer Helpline
(01553) 811000
website
www.maxview.ltd.uk
e-mail
[email protected]
TERRESTRIAL TELEVISION
BROADCASTING
Analogue
Terrestrial Broadcasting
Digital Terrestrial Broadcasting
3-5
5-6
SATELLITE & CABLE
TELEVISION BROADCASTING
Analogue Satellite Broadcasting
Digital Satellite Broadcasting
Digital Cable Broadcasting
7-8
8
8
RADIO BROADCASTING
AM Radio Broadcasting
FM Radio Broadcasting
Digital Audio Broadcasting
Satellite Radio Broadcasting
Internet Radio Broadcasting
9
9-10
10
10
10
TERRESTRIAL TV AERIALS
Types of UHF TV Aerial
–External/Loft Aerials
–Indoor Aerials
–Built-in Loop Aerials
11
11-13
14
14
TERRESTRIAL TV AERIAL
INSTALLATION
TV Aerial Position
TV Aerial Orientation
TV Aerial Alignment
TV Aerial Downlead
TV Aerial Connections
15
16
16
16
16
SATELLITE ANTENNA
Types of Satellite Antenna
System
–Domestic Satellite Antenna
–Touring Satellite Antenna
17
17
17
SATELLITE INSTALLATION
17
Coverage
17-18
Dish Size, Surface Area
and Reception Angle
Dish Alignment and Adjustment 18
18
LNB and Satellite Receiver
RADIO AERIALS
Types of FM Aerial
–External Aerials
–Indoor Aerials
–Built-in Aerials
DAB Aerials
2
19
19
20
20
20
SIGNAL BOOSTERS &
MASTHEAD AMPLIFIERS
Signal Amplification
Signal Distribution
Types of Signal Booster
–Fixed Gain Signal Boosters
–Variable Gain Signal Boosters
21-22
22
22
22
22
ACCESSORIES
TV, Radio and Satellite
23
Accessories
Coaxial Cable and
23
RF Connectors
–Fitting a Coaxial Connector
24
–Combining and Splitting
24-25
TV and FM Signals
–Fitting a ‘F’ Connector
25
Types of Outlet Socket
26
–Flush Mounted Outlet Plates
26
–Surface Mounted Outlet Plates 26
Audio/Video Accessories
Audio/Video Connections
–Scart Connector
–Phono Connector
–Scart to Phono Connector
Universal Remote Controls
Cleaning Kits
Headphones
27
27
27
27
27
28
28
28
RECEPTION PROBLEMS
Analogue Terrestrial TV
–’Snowy’ Picture
–’Herringbone’ Pattern
–’Ghosting’
–Co-channel Interference
–Electrical Interference
Digital Terrestrial TV
Analogue Satellite TV
–’Sparklies’
–Co-channel Interference
Digital Satellite TV
Intermittent Connections
29
29
29
29
29
29
29
29
29
29
29
29
TELECOMS & ACCESSORIES
Telephone
Fax Machines
Internet, Modem and
Interactive Services
Telecom Accessories
USEFUL ADDRESSES
30
30
30
30-31
32
TERRESTRIAL TELEVISION
BROADCASTING
Analogue Terrestrial Broadcasting
Terrestrial television signals were first
broadcast in the UK in an analogue
format from Crystal Palace in 1955.
Analogue terrestrial UHF television
stations are broadcast from a network
of approximately 1,000 different
transmitters around the country.
Around 50 of the total transmitter
network are high power main
transmitters. These are situated on
the highest point possible in a region,
the largest of which has a power output
of approximately 1,000,000 watts.
3
The remainder of the transmitter network
is made up of relay transmitters, smaller
lower power transmitters which receive
signals from main transmitters and
relay them to homes in areas that are
unable to receive signals from the
main transmitter. Due to the careful
planning of the transmitter network
approximately 99.3% of the UK
population are able to receive terrestrial
analogue channels (85% for channel 5).
In order to avoid interference,
neighbouring main transmitters
broadcast their signals on a different
part of the UHF frequency spectrum.
Analogue terrestrial signals are
broadcast as an electrical wave and
frequencies are allocated to individual
broadcasters with a single channel
needed for each television
programme. The complete terrestrial
UHF TV transmitting spectrum covers
the frequency range 470-860MHz.
This spectrum is split into groups of
8MHz which, are characterised by a
set of channel numbers. The following chart shows the relationship
between
frequencies, groups, channels and
aerial colour codes.
UHF TV Frequencies, Groups, Channels and Aerial Colour Codes
Frequency
470-606MHz
Aerial
Colour Code
Aerial
Group
UHF
Channel
A
21-37
Red
582-734MHz
B
35-53
Yellow
686-860MHz
C/D
48-68
Green
582-860MHz
E
35-68
Brown
470-694MHz
K
21-48
Grey
470-860MHz
W
21-68
Black
4
Television signals are broadcast on
different polarities. Main high power
transmitters broadcast their signals
horizontally and aerials, which receive
the signals from these transmitters,
are mounted with their elements
parallel to the ground. Relay transmitters generally broadcast their signals
vertically and aerials, which receive
these signals, are mounted with their
elements parallel to the mast/vertical
to the ground.
Additional services broadcast from
the transmitter along with the normal
analogue TV signal include
Digital Nicam stereo sound and
analogue Teletext. The Nicam signal
arrives at the television in a digital
format, which is then reproduced as
compact disc quality sound. To
receive this improved quality sound
you need a television that has a
Nicam facility. Analogue Teletext can
be called up from the remote control
and is much like a newspaper with
up-to-date news, the latest sports
results as well as extra information
Horizontal
mounting
about specific programmes.
The service is available on all TV
stations. Fastext allows you to instantly
call up the page information required
by using a series of coloured buttons
on the remote control.
Digital Terrestrial Broadcasting
Digital broadcasting is a more efficient
way of transmitting television services,
allowing much more information than
before to be transmitted. Digital
terrestrial television offers:
• More programmes – a mixture of
new free programmes such as BBC
News24, BBC Choice, ITV2 and
pay TV programmes from the
licensee, ONdigital.
Existing analogue programmes
–BBC, ITV, Channel 4, Channel 5
and S4C.
Sharper and clearer pictures with
cinema quality, widescreen
programmes.
Improved CD quality sound.
Digital Teletext – a greatly
enhanced version of the analogue
service. It is faster and has refined
graphics, with clearer text, more
colour and photographs.
On screen electronic programme
guides to help the viewer select
and personalise their viewing
choice.
Interactive services.
•
•
•
•
•
•
Digital terrestrial television
broadcasting uses the same UHF
frequency spectrum (470-860MHz)
and transmitter network as analogue
broadcasting and gives coverage to
most of the UK. It is planned to
transmit digital signals from 51 main
transmitter sites and 30 lower power
relay stations. Further relay
5
Vertical
mounting
transmitters may be added later.
The power output of a digital signal is
typically one hundredth the strength of
an analogue signal.
Digital broadcasting can transmit much
more information than the analogue
system by converting sound and
pictures into binary digits (zero’s &
one’s) or ‘bits’. These ‘bits’ are then
compressed so that only the data
needed to pass on the difference
between each picture frame is sent,
cutting out repetitive information and
improving quality. As digital technology
makes better use of the available
airwaves, it allows several programmes
all with high quality sound and vision
to be squeezed in the same TV
channel, occupied by one analogue
programme.
Digital terrestrial television
programmes are currently delivered
via six frequency channels or
‘multiplexes’, each carrying 4-7 TV
programmes. In order to fit the new
channels alongside the existing
analogue channels without causing
interference, each multiplex may
have a different power. Service areas
for digital transmitters may differ with
existing analogue coverage and
between different digital multiplexes.
For some transmitters multiplexes 5
and 6 may be radiated at lower power
than the others and hence are
expected to have a poorer coverage
than multiplexes 1 to 4. The multiplexes are operated by the public
service broadcasters (e.g. BBC, ITV,
Channel 4 and Channel 5) and
ONdigital who together offer a mixture
of free and subscription channels.
With digital reception, the picture will
either be perfect or non-existent. The
digital cliff refers to the rapid change
from the picture and sound being
perfect to disappearing altogether.
There will be no weak, snowy pictures.
Where possible, channels close to those
used for the analogue services have
been used. This allows the same
receiving aerial to be used for the
digital signal. A reasonable picture on
the existing aerial is a fair guide to
successful reception of digital. In some
areas of the country the digital signals
are transmitted ‘out of group’ to the
current analogue signals. In these
cases, a new wideband UHF TV aerial
may be necessary for reception of the
digital services. In fringe and overlap
areas you may need to change your
aerial direction and point it at a
different transmitter to receive a
satisfactory digital service. Contact a
professional aerial installer for further
information.
If you wish to receive ONdigital’s
subscription programmes you will need
a smart card and to subscribe ONdigital.
To receive a digital terrestrial signal,
you will need either a digital terrestrial
set-top box receiver or an integrated
digital television with a built-in
terrestrial decoder. A digital terrestrial
set-top box receiver is used with your
existing analogue TV. The most basic
form of decoder will receive free to
air programmes from the existing
broadcasters. The basic decoder will
also have an electronic on-screen
programme guide to guide the viewer
through the multitude of options available and enhanced digital Text pages
with high resolution graphics. The settop box will be easy to set up and will
link to the TV, VCR and aerial socket
and be operated by a remote control.
It is the long-term goal of the
government to switch off analogue
transmissions sometime in the future
and transfer all television channels to
digital frequencies, however, this is not
likely to happen until 2006-2010. In the
meantime the BBC, ITV, Channel 4 and
Channel 5 must simulcast i.e. transmit
80% of their programmes both as
analogue and digital.
‘Centre cut out’
‘Centre cut-out’ where the sides of
the widescreen picture are cropped.
‘Letter box’
‘Letterbox’ format, with black bands at
the top and bottom of the screen.
‘Zoomed’
‘Zoomed’ or ‘stretched’ where the
picture is expanded to fill the full screen.
‘Pillar box’
‘Pillar box’ format with black bands on
either side of the screen.
For digital transmissions, all the main
broadcasters have given their
commitment to making and transmitting
widescreen programmes. The screen
proportion is 16 units wide and 9 units
deep, rather than conventional
proportions of 4 units wide and 3 deep.
Viewing a 16: 9 image on a 4:3 screen
Original 16:9 image
A widescreen television will give you the
best digital rendition of the new medium.
However, if you don’t have a widescreen
TV, you will still be able to see digital
widescreen broadcasts as either a ‘centre
cut-out’ or ‘letter box’ format.
Viewing a 4:3 image on a 16:9 screen
Original 4:3 image
To watch older 4:3 pictures on a
widescreen TV, you will be able to view
either a ‘zoomed’ or ‘stretched’ format
6
SATELLITE & CABLE
TELEVISION BROADCASTING
Analogue Satellite Broadcasting
Satellites, which relay TV signals, are
positioned in different orbital
positions at a distance of 35,615km
above the earth’s equator. A satellite
positioned at this distance takes 24
hours to orbit the earth and is said to
be in geostationary orbit, as it is
always in the same position above
the earth.
In Europe, Astra and Eutelsat are two
of the main TV broadcasting satellites.
The Astra analogue satellites are
co-located at the orbital position
19.2° East above the equator and
the main Eutelsat TV Satellites are
located at 13° and 16° East.
W
E
60°
60°
40°
40°
20°
20°
0°
7
Satellite operators transmit their
signals at a very low power from large
parabolic aerials on the ground to the
satellites. The satellite then amplifies
these signals, converts them to a
different frequency and transmits them
back to earth towards your satellite
dish. Each satellite has many transmitting antennae, which transmit different
channels or programmes to different
European regions. The transmitting
ray of a single antenna is called a
‘beam’. This beam that reaches
the earth is called the ‘footprint’.
Signals are stronger in the
centre of the footprint, getting
weaker towards the edge.
To receive a satellite
signal you will need a dish
which is a suitable size
and shape, LNB and analogue
satellite receiver. Reception of satellite
signals is covered in greater detail in
the Satellite Installation section.
Digital Satellite Broadcasting
In the UK digital satellite television
from BSkyB launched during 1998
with near nationwide coverage. BSkyB’s
digital satellite television service offers
hundreds of channels, a mixture of new
basic and premium services, including
a large number of subscription and pay
per view services, near-on-demand
movies (the same title starting every 10
or 15 minutes) and enhanced football
coverage. BSkyB also offers new
interactive services initially via a
telephone modem in conjuction with
British Interactive Broadcasting.
BSkyB’s digital satellite television
service is beamed down from the Astra
satellites located at the orbital position
of 28.2° East. If you already have a
satellite system and wish to receive
BSkyB’s digital satellite signals.
You will need a new BSkyB digital
satellite set-top box receiver or a new
integrated digital television with built
in digital satellite television decoder.
You will also probably have to change
your dish to a smaller digital dish and
you will need a new LNB. For digital
satellite reception the dish must be
positioned for the new orbital position,
so if you still wish to receive the
existing analogue (non-BSkyB digital
services) and new digital signals then
8
you will need two satellite dishes.
See Satellite Installation section for
further information on reception of
digital satellite signals.
Digital Cable Broadcasting
Digital cable television was launched
nationally during 1999 and offers
hundreds of new channels. Digital
cable television is transmitted via the
existing cable TV lines and is operated
by the major cable organisations. You
will need a new digital cable set-top
box receiver linked to your current
television or new digital television
with built in digital cable receiver/
decoder. For further information,
contact your local cable operator.
RADIO BROADCASTING
Radio
In the UK there are currently five BBC
national networks, Radios 1,2,3,4 and
5 Live and three regional networks,
Radio Scotland, Radio Wales and
Radio Ulster. In addition to this there
are approximately 40 BBC local
stations in England. There are also
independent national networks, such
as Classic FM, Virgin and Talk Radio,
which are controlled by the Radio
Authority. In addition there are over
200 local independent stations
– ranging from regional stations, to
local stations covering a single city or
area. These radio stations are spread
across the AM, FM, DAB and Satellite
Radio spectrum.
9
AM Radio Broadcasting
AM (amplitude modulation) is used
to describe the long wave (LW) and
medium wave (MW) bands. AM radio
signals are broadcast from national
and regional transmitters covering the
frequency spectrum 153-1602KHz.
The signals are transmitted in an
analogue format where radio waves
directly represent the original sound.
AM radio signals offer convenient
sound, however can be easily affected
by the weather. For higher quality
sound choose FM or DAB.
FM Radio Broadcasting
FM (frequency modulated) radio
signals are broadcast from regional
transmitters covering the Band 2
frequency spectrum from 88-108MHz.
The signals are transmitted in an
analogue format and offer high
quality stereo sound. On the FM
waveband, local and national stations
are interleaved along the frequency
band and different frequencies are
required to broadcast a single
programme over a large area.
For example the table shows that
BBC Radio 1 broadcasts on several
frequencies between 97-99MHz.
Retuning is necessary throughout
the country.
Digital Audio Broadcasting
Digital technology has also revolutionised radio broadcasting with the
first pilot Digital Audio Broadcasts
appearing in September 1995. Near
universal coverage of the UK is the
longer term objective, as with
analogue television, the long-term
goal of the government is to use the
analogue spectrum for other
applications.
Digital Audio Broadcasting or Digital
Radio as it is more usually referred to
converts digital speech, music and
data signals into ‘binary digits’ to
resist interference and to transmit
information more efficiently allowing
more programmes to be broadcast.
Digital Radio has the following
benefits over FM and AM radio:
•
•
•
•
•
Reliable, interference free
reception on all receivers e.g. Hi-fi
systems, car radio and portable
radio.
CD quality sound.
No retuning-same frequency is
used for programme nationwide
(Single frequency network).
More programme choice.
New services-text, graphics and still
pictures.
In the UK Digital Radio broadcasts in
the Band 3 spectrum between 217.5
MHz and 230MHz, split into seven
1.55MHz blocks called multiplexes.
The multiplexes provide 8 national
BBC radio stations, 8 national
commercial radio stations and 16
different local stations.
Frequency
(MHz)
108
Local
radio
stations*
102
Classic
FM
99.8
BBC
Radio 1
97.6
Local
radio
stations*
94.6
BBC
Radio 4
92.4
BBC
Radio 3
90.2
BBC
Radio 2
88
Table shows frequency range
for national FM radio stations.
*For specific local FM radio
stations see your area
programme listings guide.
10
To receive digital radio, you will need
a digital radio receiver and a digital
radio aerial. You may not need a
directional antenna in the loft or on
the roof to achieve the best results, as
with FM. With digital radio, you either
get an error-free sound and data
signals or if you are outside the
reception area, nothing at all.
Satellite Radio Broadcasting
In Europe, two of the main satellite
television broadcasters, Astra and
Eutelsat, also broadcast UK national
and regional radio stations both from
the BBC and independent broadcasters, alongside satellite TV stations.
As with analogue satellite television,
Astra broadcasts analogue radio from
the orbital position of 19.2° East and
Eutelsat broadcasts from the Hotbird
satellite 13° East. Digital radio is
currently broadcast from Astra at
the orbital position of 28.2° East.
Radio services via digital satellite
provides:
quality sound.
• Digital
Near nationwide digital radio
• coverage.
Increased choice of radio services.
• Regional
programmes available
• near nationwide.
Selection of exclusive digital radio
• services.
To receive satellite radio, you need to
have an appropriate satellite receiver,
either analogue or digital depending
on the service to be received,
connected to a satellite dish. The
majority of satellite radio stations
are free to air and require no
subscription. Satellite radio stations
can either be played through the
television’s speakers or connected to
a Hi-fi for improved quality sound.
Internet Radio Broadcasting
Many radio stations now have internet
web sites and make their radio or
audio services available via the web.
To receive Internet Radio you need an
internet connection supplied by an
Internet Service Provider, a computer
with a modem and sound card, world
wide web browser software and
‘streaming’ audio software. A good
quality sound card and speakers will
be required to appreciate the Hi-fi
sound reproduction available via the
internet. Music can be customised and
downloaded onto MP3 style players
for listening at a later date.
TERRESTRIAL TV AERIALS
Types of UHF TV Aerial
There are three basic categories of
UHF TV aerial:
1. External/Loft Aerials
For DIY installations, wideband (group
W) television aerials are readily
available and may be used for
reception of all UHF TV channels. Their
usage will increase significantly with
the advent of Digital Terrestrial
Television.
11
Grouped aerials (group A,B,C/D,E,K)
–see chart page 4 are generally
available from more specialised
outlets and are usually fitted by
professional aerial installers who have
knowledge of the local transmitters.
They receive specific channels and
due to a narrower bandwidth are of a
higher gain than wideband aerials.
Reflector
14 element UHF TV aerial
Insulator cap
Clamp
Elements
Dipole
Boom
18 element UHF TV aerial
Mast
Coaxial
cable
10 element UHF TV aerial
For the best reception, it is
recommended to mount your aerial
externally in as high as a position as
possible. Aerials can be mounted in
the loft space or on an outside wall,
but in weak signal areas or where
trees or large buildings cause
obstructions picture quality may be
reduced and an external aerial should
provide an improved signal.
See Terrestrial TV Aerial Installation
section for further information.
In addition, the aerial should also be
of good quality with sufficient
elements (crossed strips) to deliver
enough signal to your television.
When looking for an aerial there
is usually a
and will receive more of the incoming
signal to provide the best possible
television picture in a weaker signal
area. For reception of digital terrestrial
signals a larger element aerial may be
required.
Aerials are also available in kit formats
for DIY assembly which come complete
with mast, cable and fixing accessories.
are supplied with internal or
external signal boosters. They do
not need alignment or adjustment
when travelling from location to
location. For digital reception
directional aerials are recommended
as they pick up more signal and offer
greater rejection to unwanted signals
than omnidirectional aerials.
For touring applications, directional and
omnidirectional aerials are available.
Directional aerials such as the Mobile
Gold, must be pointed towards the
transmitter and need to be realigned at
every new location to receive a signal.
Adding a signal booster can improve TV
reception. Omnidirectional aerials, such
as the Omnimax and Gazelle, receive
all available signals throughout
UHF TV aerial
Omnimax mobile aerial
choice between 10 element, 14
element and 18 element UHF TV
aerials. Generally the larger number of
elements, the more is received by the
aerial. A high gain UHF TV aerial has
more elements than a standard aerial
12
43 element high gain
UHF TV aerial
23 element high gain
UHF TV aerial
UHF
TV aerial
kit
Mobile Gold mobile aerial
High gain
UHF TV aerial
!
2. Indoor Aerials
In strong reception areas a set top or
indoor aerial can be used to receive
terrestrial television signals, however,
the best quality reception will always
be obtained using an external aerial,
mounted either on the chimney or
wall. Set top aerials will however
improve signal reception to televisions
which cannot receive a signal from an
external or loft mounted aerial, or
compared to built in loop aerials.
They are often used with portable
televisions in bedrooms etc. Set top
aerials are wideband aerials and are
capable of receiving all available
UHF terrestrial television signals
from the local transmitter. As TV
signals available inside a room are
variable ensure the aerial has a length
of coaxial cable long enough to move
the aerial to the best possible
reception position.
There are two types of indoor aerial.
The first is a directional, which you
point towards the transmitter and
move around the room to find the
best signal. The Truvision, Horizon
and Contour are all examples of good
quality directional indoor aerials. If
the signal is weak, you should choose
an indoor aerial with good low noise
amplification such as the Contour Plus
which has an integral battery
operated signal booster or the
Horizon Plus or T-Vision which both
have separate
mains powered Signal Boosters. The
gains of these Maxview signal boosters
have been optimised for reception of
digital terrestrial UHF TV signals.
The second type is an omni-directional,
which receives all the available
signals throughout 360 degrees, but
still needs placing in the best possible
position in the room. The Omnivision
receives all available UHF TV and FM
signals throughout 360 degrees and
comes complete with a separate fixed
gain signal booster with variable gain
on the antenna section.
by external interference and usually
gives unsatisfactory results.
An indoor aerial for example
Truvision, or Horizon will
give improved reception
compared to a
built-in loop
aerial.
Telescopic
TV aerial
3. Built-in Loop Aerials
A built-in loop or telescopic aerial,
normally supplied with the TV, is the
least effective of all the aerials as it has
low gain and is fixed in position in the
room (on the back of the television
set). It is capable of receiving all of the
available signals but is easily affected
Built-in
loop TV
aerial
Horizon
directional
TV aerial
Truvision directional TV aerial
14
Contour Plus
directional
TV aerial
with signal
booster
TERRESTRIAL TV AERIAL
INSTALLATION
TV Aerial Installation
The best reception is always obtained
when the correct type of aerial is
installed in an outside position, high
enough to clear local obstructions
and pointing in the direction of the
transmitter. Aerial height may need
some final adjustments to give the
best reception on all terrestrial
channels. The following guidelines
will ensure you can achieve the
best possible reception.
Loft
fixing
600mm
TV Aerial Position
Before installing a new aerial check
that your existing mast is in good
condition. If you are adding an
additional TV aerial ensure that the
mast is long enough to allow a
minimum vertical
separation of 600-650mm (2ft approx)
between the two UHF TV aerials.
To receive the best interference free
reception it is essential to fit the aerial
as high as possible, free from
obstructions. It is recommended that
the aerial is mounted externally on a
mast, on the eaves or on an outside
wall or balcony. If you do not have
external access the aerial can be
mounted in the loft but the picture
quality may be
Wall
fixing
Chimney
fixing
dramatically reduced compared to
external mounting. For analogue
reception, correct positioning of aerials
is particularly important for reception of
digitally-coded analogue signals such as
Teletext and Nicam. Ghosting caused by
reflected signals, which may not be
noticeable on normal television
pictures, can cause errors or missing
letters in text on screen.
For digital terrestrial reception the
aerial position is very important to
ensure that there is no signal drop out.
The digital cliff refers to the very rapid
change from perfect pictures and sound
to non-existent pictures or sound.
Eaves
fixing
15
Chimney, Wall and Loft Fixing Kits are
all available to provide the best fixing
for chosen mounting location.
TV Aerial
Orientation
Ensure the aerial
is mounted either
vertically or horizontally to match the
polarity being broadcast from the
chosen transmitter. Incorrect polarity
can easily result in only picking up a
quarter of the signal as well as being
susceptible to some forms of interference. Refer to a transmitter guide to
check polarity or look at your
neighbours aerials.
Wall fixing kit
Horizontal
mounting
Vertical
mounting
Chimney fixing kit
TV Aerial Alignment
To get the best signal the aerial must
be accurately aligned. There is a
simple three step alignment procedure
for the best analogue reception:
1.Turn your aerial to the LEFT until the
picture is lost.
2.Remember this position and turn
the aerial to the RIGHT until the
picture is lost.
3.Now point the aerial in the centre
of these points to receive the best
reception.
3
This alignment will not work for digital
signals as with digital the picture and
sound are either there or not there.
There is no gradual degradation of
signal. To tune in digital signals, first
tune in the analogue channels and
then refer to the manufacturer’s
instructions of your digital terrestrial
equipment for further guidance. You
may need to call in a professional
aerial installer or ONdigital for advice.
2
1
TV Aerial Downlead
To minimise any signal losses between
the aerial and the TV, it is essential to
use the shortest possible practical
lengths of good quality screened
coaxial cable. There should be no sharp
bends in the cable and to avoid
crushing of the cable any cable clips
should not be hammered home too far.
TV Aerial Connections
These must be correctly terminated
with tight connections on the outer and
inner at both the aerial terminals and
TV plug end of the downlead.
16
Types of Satellite Antenna System
There are two basic categories of
satellite antenna system:
SATELLITE
ANTENNA
1. Domestic Satellite Antenna
Domestic satellite antenna are
normally installed either on a mast,
the chimney or wall or alternatively
strategically placed in the garden to
camouflage the dish.
2. Touring Satellite Antenna
Touring satellite antenna are used for
touring vehicles such as caravans and
motorhomes. They are available to
either fix permanently on a through
the roof fixing or to be used together
with a mast or tripod fixing. The main
advantages of a permanently fixed
through the roof mounted satellite
system is that all alignment and
adjustment can be made from inside
the touring vehicle when you want to
watch satellite. The more advanced
permanently fixed satellite systems
have an electric motor which enables
the dish to raise automatically and
self seek the satellite.
SATELLITE INSTALLATION
To receive a satellite signal you must
be within the coverage area or
footprint of the satellite. Other criteria
which must be considered are the
shape and size of the dish, the surface
area, the reception angle, rejection of
signals from unwanted satellites and
ease of alignment.
Coverage
The predicted coverage of a satellite
signal is shown by a footprint.
Satellite footprints show under optimum weather conditions i.e. clear
skies, no rain, cloud etc. the signal
strength (dBW) required to receive a
picture in a certain location. Satellite
signals are stronger in the centre of
the footprint getting weaker towards
the edge. Clouds, rain or snow
decrease the
signal strengths and with analogue
signals picture distortion in the form
of black and white ‘sparklies’ can
appear. In severe weather conditions
this can result in a complete loss of
picture. With digital signals the
picture and sound block or disappear.
It is also important to bear in mind
that not every channel received
from the chosen satellite will be
received with the same signal
strength.
Dish Size, Surface Area and
Reception Angle
The choice of dish size is dependent
on your location in the UK and hence
the signal strength in the area in
which you wish to receive the signal.
The weaker the signal the larger the
dish size required to receive a picture.
Larger dish sizes will be needed in
Scotland, the north of England and
areas which receive a high rainfall.
The size of the dish also effects the
surface area and reception angle of
the dish. Larger dishes have greater
surface areas and therefore can
receive more signal. For example, a
48cm dish has 53 per cent more
surface area than a 38cm dish and
therefore receives 53 per cent
more signal.
45dBW
48dBW
50dBW
52dBW
Dish
Size
Signal
Strength
38cm
52dBW
48cm
50dBW
60cm
48dBW
80cm
45dBW
80cm
60cm
48cm
38cm
38cm
+53%
+150%
17
60cm
48cm
+63%
60cm
+100%
In adverse weather conditions,
degradation in picture quality is not as
obvious with a larger dish, providing
both dishes are accurately aligned.
Smaller dishes have larger reception
angles than larger dishes. For example,
a 38cm offset dish has a reception
angle of 5° whereas a 60cm dish is
only 3°. With larger reception angles, it
is easier to locate the satellite and dish
will only need fine adjustment.
However, a smaller reception angle will
give greater immunity to interference
from adjacent satellites and receive
more signal.
22
24
26
28
30
32
34
36
38
40
42
44
Dish Alignment and Adjustment
To receive a clear satellite picture the
dish must have the correct Vertical
(or Azimuth) and Horizontal Alignment.
Vertical alignment is the dish angle of
elevation and refers to the angle at
which the satellite signals hit the
earth’s axis. In the northern hemisphere they are flat - about 15° and the
further south you go i.e. nearer to the
equator, the steeper they become. On
Sicily they have an elevation angle of
45° . Horizontal alignment is the position of a satellite relative to where you
wish to receive the signal and requires
the dish to be turned until the satellite
signal
is received.
For analogue satellite reception, first
make sure that your television is tuned
to the output channels of the satellite
receiver and that the receiver is tuned
to a known Astra or Eutelsat satellite
18
channel. Correct dish alignment can
be helped with the use of a basic
compass. Once the dish is aligned left
to right with the compass bearing
(e.g. Astra 1 satellites are located at
19.2° East of South and Astra 2 digital
satellites at 28° East of South), the dish
can then be adjusted to the correct
vertical elevation. Using the TV picture
as a guide, slowly elevate the dish
until a clear picture is found. Alignment
is fairly critical and the dish must be
within a few degrees before any
picture or sound will be observed.
If after elevating the dish the picture
is still full of ‘sparklies’ you may then
need to fine tune the bearing of the
dish by slowly moving the dish from
left to right and/or vertically until a
clear picture is found. When tightening
the dish mounting bolts take care not
to move the dish position. For digital
satellite reception, the dish alignment
is basically the same as with an
analogue system. Instead of using the
picture as a guide most digital satellite
receivers have a signal strength meter
built into them. Also move the dish in
slow discrete steps in order to allow
time for the digital meter in the satellite
receiver to respond correctly. Consult
the manufacturer’s instruction manual
for more details.
LNB and Satellite Receiver
The signals are then focussed by the
dish to strike the focal points within the
Low Noise Block (LNB). The High and
Low Band are selected by a 22KHz
tone and vertical and horizontal signals
from the satellite are selected by
changing the voltage supplied to the
LNB from the receiver. These signals
are then
converted to a lower frequency
between 950-2150MHz which can be
sent down the coaxial cable to the
receiver. If you already have a satellite
system it is possible to upgrade your
LNB to provide improved picture
reception, or receive more channels.
This can be done by installing an
enhanced or universal LNB. A twin LNB
has two outlets that enable two satellite
receivers to be fed from one dish. The
satellite receiver is the final part of the
chain before the TV and is where all the
signals that are collected by the dish
are converted into a format that the
television can display. This is also the
unit into which a decoding (Sky TV)
card is inserted to allow you to watch
your subscription channels.
RADIO AERIALS
Omnidirectional
dipole FM aerial
Types of FM Aerial
There are three basic categories of
FM aerial:
1. External Aerials
An externally mounted FM aerial will
supply your Hi-fi system with the best
possible FM radio signals. There are
two main types of FM aerial for
external use – directional and
omnidirectional aerials.
Omnidirectional FM aerials
Directional aerials must be pointed
directly towards a single transmitter
to receive the signal such as a dipole
mounted horizontally. Directional
high gain FM aerials are also available from professional aerial
installers.
Omnidirectional aerials, which can
be either a straight dipole mounted
vertically or a C-shape mounted
horizontally, receive signals throughout 360 degrees. The quality of
reception is slightly less than that
from a directional aerial, but the
advantage is gained when wanting
to receive more than one FM
transmitter signal.
19
Directional FM aerials
2. Indoor Aerials
If you are unable to fit an external or
loft FM aerial, an indoor aerial
combined with a signal booster is the
next best option. The Profile Plus is a
good quality indoor FM aerial
designed to provide a good quality
signal and to co-ordinate with
modern Hi-fi systems.
3. Built-in Aerials
There are two other types of FM
aerial, which are usually supplied by
the equipment manufacturer. One is
a ‘T’ shaped piece of plastic coated
wire, which when laid in position has
the same characteristics as the dipole
shown on the previous page (both
omnidirectional and directional).
The second is a telescopic type aerial,
which is fitted directly to the rear or
top of a portable FM receiver. Both
types of aerial are affected by
interference caused by people moving close to it and are the least effective of FM aerials.
DAB Aerials
To receive digital radio, you will need
a digital radio receiver and a digital
radio aerial, but you may not need a
directional aerial in the loft or on the
roof to achieve the best results. With
digital radio, you either get an
error-free signal or if you are outside
the reception area, nothing at all. If
you need an aerial for Digital Radio a
VHF aerial which covers the Band 3
between 217.5-230MHz is
recommended.
20
Signal Boosters and Masthead
Amplifier products are designed to
amplify UHF TV and FM radio signals
and distribute TV, Radio, Video and
Satellite signals. A Signal Booster is
the term used for a DIY unit used to
boost or distribute a signal. It is either
placed in the loft, in a convenient
position in the house, or behind the
main TV set.
SIGNAL BOOSTERS
& MASTHEAD AMPLIFIERS
In the very weakest reception areas a
high gain aerial and masthead
amplifier will be required. A masthead
amplifier is more likely to be used by
a professional aerial installer and is
installed on an external TV aerial
mast. The amplifier receives d.c.
power from a masthead power supply
unit located indoors. This unit is
mains powered and connects between
the amplifier and TV, providing the
best possible signals for TV and FM
radio.
Signal Amplification
In many areas, the incoming TV signal
may be quite weak and although a
larger element aerial may be used,
the TV signal may still need some
improvement.
This sort of problem can often be
overcome for both television and
radio with the use of a signal
booster which amplifies the
incoming signal and can
be split at the outgoing
socket to TV and/or FM radio.
A booster may also give an
improvement where long lengths
of coaxial cable reduce signal
power.
Signal
booster
TV
TV
TV
TV
TV
Video
Signal
booster
Signal booster
installed in loft
(video to 1 TV)
Signal booster
installed in room
(video to 3 TV’s)
21
Video
TV receiving digital
signal
TV receiving digital
signal
TV receiving digital
signal
TV receiving digital
signal
TV aerial
Video
recorder
FM aerial
Signal
booster
TV/FM
diplexer
TV/FM
diplexer
TV/FM
diplexer
TV/FM
diplexer
Digital
terrestrial set top
receiver
Hi-fi
TV/FM
diplexer
Hi-fi
Hi-fi
Hi-fi
TV, FM, Video and Digital to all TV’s
For amplification of digital terrestrial
television signals, it is important to
use a low noise signal booster with
low gain and good signal handling.
In the distribution chain, the digital
terrestrial television set top box
should be placed before the video,
digital satellite receiver or analogue
TV to minimise degradation of the
digital terrestrial signals.
Signal Distribution
Signal boosters can also be used to
distribute analogue and digital UHF
TV, FM Radio, DAB, Video and
analogue and digital Satellite outputs
to many outlets around the home
without loss of quality. To ensure the
best quality signal distribution, ensure
the booster is located as close to the
TV and/or FM aerial as possible.
When distributing a digital terrestrial
signal and existing analogue signals
around the home, like with satellite,
you will only be able to distribute the
programme, which is selected on the
set top box receiver.
In strong signal areas, a splitter may
suffice to split a signal for distribution.
See Combining and Splitting Signal
section for more information.
Types of Signal Booster
There are two basic categories of
indoor signal booster:
1. Fixed Gain Signal Boosters
The fixed gain signal boosters come
in a range of 1,2,3,4,6 and 8 outlet
models. The 1,2,3 and 4 set models
are designed to be plugged directly
into a convenient 13amp mains socket,
making them ideal for installing close
to the TV or audio equipment.
These models are ideal for smaller
domestic installations. The 6 and 8 set
models are fitted with a mains lead
and plug, enabling them to be located
away from the mains socket. These
models are generally used in larger
installations or for flats and offices.
2. Variable Gain Signal Boosters
The variable gain signal booster range
is available in 1,2,3 and 4 outlet models. The units are fitted with a mains
lead and plug, enabling them to be
located away from the mains socket.
Each model has a variable gain control
allowing fine adjustments of the signal
strength to achieve the best possible
picture and sound quality.
For further information regarding
installations requiring more than 8
outlets or for integrated digital
televisions contact the Maxview
Customer Helpline.
Signal booster with
variable gain control
Plug in signal booster
Fixed gain signal booster in loft
22
ACCESSORIES
TV, Radio and Satellite Accessories
Coaxial Cable and RF Connectors
When one end of a coaxial lead has
been connected to an aerial (TV,
Satellite or Radio) you will usually
need to connect a RF connector to the
other end for it to plug into your
television, satellite receiver or Hi-fi.
There are two main types of RF
connector. The one used in the
majority of cases is a screw together
and ‘push in’ type, called a coaxial
connector. The second is a screw on
and screw in type, called an ‘F’
connector, mainly used for satellite,
cable, professional use or for
mobile vehicles where a
secure fixing is needed
that will not disconnect
over a long period
of time.
There are many different types of
coaxial cable. As a signal travels along
the cable, it begins to lose some of
its strength. Therefore the best
types of cable are ‘low loss’ double
screened or tape and braid which
lose the least amount of signal.
Usually, the thicker the cable, the
lower the loss and the better the
screening.
23
Fitting a Coaxial Connector
1
First cut cable to required
length and then unscrew
coaxial plug and slide
screw cap over cable.
5
2
3
Strip away about half of
the inner insulation around
the inner copper wire.
Check that none of the
copper braid is touching
the inner copper wire.
Strip away approximately
23mm of outer insulation.
Next, gather strands of
copper braid together and
wind back around the
outer insulation.
* If cable is tape and braid, cut
tape to be flush with outer
insulation
Screw
cap
Outer
insulation
Cut off inner copper wire
flush with plug.
4
Copper
braid
Inner
insulation
Open claw, slide over
copper screening and pinch
to tighten. Loosen screw in
plastic connector slide over
inner copper wire. Tighten
screw* securely ensuring
head of screw does not
protrude above plastic.
Do not over tighten.
Reassemble coaxial plug
* If plastic connector does not
have retaining screw, an effective
connection will still be made by
re-assembling the plug.
Brass claws
‘Push-in’
type connector
Inner
copper wire
Centre
stem
Copper
braid
Inner
insulation
Outer
insulation
TV aerial
Tape
TV aerial
TV 2 way
splitter/combiner
24
Inner
copper wire
Combining and Splitting TV Signals
Signals from two different regional
analogue transmitters, broadcasting
different regional analogue TV
programmes, can usually be combined
into the same downlead cable using
a TV 2 Way Splitter/Combiner. A TV
2 Way Splitter/Combiner can also be
used to split analogue or digital TV
signals to 2 outlets, however this is
only recommended in a strong signal
area, as splitting reduces the strength
to each outlet. Strong FM or DAB
signals can also be split in the
same way.
Fitting an ‘F’ Connector
1
2
First cut cable to required
length.
3
Strip away approximately
15mm of outer insulation.
Next, gather strands of
copper braid together and
wind back around the
outer insulation.
Strip away about half of
the inner insulation around
the inner copper wire.
Check that none of the
copper braid is touching
the inner copper wire.
* If cable is tape and braid, cut
tape to be flush with outer
insulation
5
4
Feed the inner copper wire
through connector and
screw clockwise to tighten.
Outer
insulation
Inner
insulation
Inner
copper core
Copper
braid
Cut off inner copper wire
to extend 3 mm beyond
plug body.
TV aerial
Screw on
‘F’ connector
Combining and Splitting
TV and FM Signals
If you have both a TV and FM aerial,
it is also possible to combine both
of these signals into one downlead
cable, using a TV/FM diplexer.
A diplexer unit contains electronic
components, which combine two
signals with maximum efficiency.
When a diplexer is used to combine
TV and FM signals it stops FM sound
affecting TV pictures and vice-versa
and when used to split signals, it
maintains equal signal strength to
both TV and FM outlets.
FM aerial
TV/FM
diplexer
Strong TV, FM or DAB signals can be
split to 3 outlets using a TV/FM 3 Way
Indoor Splitter.
25
Types of Outlet Socket
1. Flush Mounted Outlet Plates
If you are installing a complete home
distribution system and have easy
access to the wall, flush mounted
outlets are the best way to supply TV
and FM to each room. Flush mounted
outlets fit on a standard 25mm deep
single metal mounting box, which is
recessed into the plaster. Alternatively
they can also be mounted on plastic
surface mounted boxes.
TV aerial
A TV/FM Diplexed Outlet Plate is the
most effective outlet plate as it
electronically splits the signal from a
single downlead cable to one TV
and one FM outlet with minimum
loss of signal quality. If only a TV
aerial is used at present, it still
allows a FM aerial to be installed at
a future date, provided a TV/FM
diplexer is put in the loft.
FM aerial
TV/FM
diplexer
For a single TV or FM downlead Single
Flush Outlet Plates are available and
Twin Flush Outlet Plates for two
separate TV and FM downleads.
Flush outlet plates are also available
for satellite with a single female ‘F’
socket and a dual downlead version
for satellite and TV with a female
coaxial socket and female ‘F’ socket.
2. Surface Mounted Outlet Boxes
If you have surface mounted the
coaxial cable, use surface mounted
outlet boxes. For a single TV or FM
downlead a Single Surface Outlet
Box can be used. A TV/FM Twin
Surface Outlet Box contains
a resistive splitter so a
single downlead can
feed two separate TV and
FM outlets.
In situations where two different TV
(or two FM) aerials, receiving separate
transmitter signals come into a house,
a switched type box could be used.
This allows manual switching to
receive each transmitter separately if
difficulties arise in combining two
aerials. Alternatively a diplexer could
be used to combine the two signals.
For information on combining aerials
contact Maxview Customer Helpline.
Coaxial plug
into TV
TV/FM
diplexed
outlet plate
Coaxial cable
connection
Connecting Coaxial Cable in
Outlet Socket
Cut cable to required length. Strip
away approximately 23mm of outer
insulation. Next, gather strands of
copper braid together and wind back
around the outer insulation. Strip
away about half of the inner
insulation around the inner copper
wire. Secure the inner copper wire
26
beneath the screw down terminal,
and tighten the circular metal clamp
down over the copper braid. Trim the
inner flush with the centre screw and
make sure no strands of braid are
loose and able to touch the central
core and short out the signals. Then fit
the cover of a surface mounted outlet
or screw the faceplate of a flush
mounted one to its mounting box.
To connect from the outlet socket to
the Television, Radio, Satellite Receiver
or Cable Box, fly leads (or extension
cables) are available in 2m, 4m and
10m lengths with either coaxial or ‘F’
type connectors.
TV or FM
single flush
outlet plate
(1 in, 1 out)
TV or FM
twin flush
outlet plate
(2 in, 2 out)
TV or FM
single surface
outlet box
(1 in, 1 out)
TV/FM
twin surface
outlet box
(1 in, 2 out)
TV/FM
diplexed
outlet plate
(1 in, 2 out)
TV or FM
switched surface
outlet box
(2 in, 1 out)
Audio/Video Accessories
Audio/Video Connections
Audio/Video accessories are used to
enhance the sound and picture quality
of your equipment.
There are basically two types of
audio/video connector scart and
phono.
Scart Connector
This method of connection was
designed as a European standard that
would allow equipment to communicate directly with each other and
improve picture quality. When a scart
connector is plugged into a TV, Video
or Satellite receiver, the signal travels
process which occurs if coaxial plugs
and cable are used to connect
equipment via RF leads. A standard
scart to scart lead has 21 individual
connections carrying different signals.
Many of the pins are opposite to each
other, this allows a lead to be
connected either way round. You may
need to select the A/V mode on the
equipment to choose the scart path
for the signal, if the equipment does
not auto select.
Phono Connector
Most TV, Video, Satellite and Hi-fi
systems have phono connectors for
convenient interconnection of sound
or vision signals between equipment.
A phono connector plug carries the
equivalent to 1 of 21 pins in a
scart plug.
Scart to Phono Connector
If new and older equipment are being
used together it may require a scart
to phono connector lead.
Scart
connector
between them via the most direct
route possible. This ensures high
quality picture and sound are
maintained, avoiding the translation
Surround Sound
There are a number of different types
of ‘Surround Sound’ offered by
equipment manufacturers, the main
ones are Dolby* Surround and
Dolby* Pro-Logic. Surround offers two
speakers at the front and two at the
rear. Pro-Logic however offers two
speakers at the front and two at the
27
rear and an additional centre speaker
at the front. With both systems the
two front speakers supply stereo
sound and the two rear speakers
create special affects. The centre
speaker with Pro-Logic carries the
dialogue from the actors on screen.
*Dolby is a trademark of Dolby
Laboratory Licensing Corporation.
Phono
connectors
If your equipment doesn’t have
surround sound, but your television
and video has either scart or phono
connectors, it is possible to produce
it via the Hi-fi.
Universal Remote Controls
There are two basic categories of
Universal Remote Control:
1. Replacement for Lost or Broken
Remote Control
The most basic one way universal
remote controls are intended as
replacements for lost or damaged
original manufacturer’s handsets.
This is often a much cheaper
alternative than purchasing a
manufacturer’s own direct
replacement remote control.
2. Multiway Replacement
Multi-function units can be used to
replace multiple handsets to allow
you to control for example your
analogue or digital TV, Video, Satellite
receiver or cable box even Hi-fi from
one handset.
The universal remote controls may
also have additional features which
include:
Cassette
cleaning kit
•
Video
cleaning kit
Direct buttons for digital terrestrial
television and digital satellite
television functions.
Each universal remote control
contains a micro-chip that holds a
library of infra-red codes. These codes
cover the vast majority of equipment
sold in the UK. All you have to do is
enter the maker’s code for each piece
of equipment to be controlled, store
the code and it is ready to use.
CD lens
cleaning kit
Cleaning Kits
Cleaning Kits are available for
Cassette, Video and CD Lens to
maintain the performance of your
equipment. For the best results they
should be used on a regular basis.
Headphones
To enjoy the sound from your audio
equipment such as TV and Hi-fi
without disturbing others, headphones
are available in three basic categories
of in-ear, open and closed back.
• Timers and programmable AV
system controls.
• Macro functions, which can switch
•
on and configure two or three
devices with a single button press.
Learning facility for any type of
infra-red equipment for example a
Hi-fi or even garage doors. The
learning facility allows the Remote
Control to be ‘taught’ the function
of another remote by placing them
head to head and setting the keys.
The original remote control must
be available for the new unit to
learn its information from
and these units can only
learn functions that
your original remote
control was
programmed
to accept.
Open stereo
headphones
In-ear
headphones
28
Closed stereo
headphones
Analogue Terrestrial TV
‘Snowy’ Picture
A generally faint or grainy television
picture, often referred to as snow, is
generally caused by a weak signal.
Normally the TV transmitter will be a
long way away. A possible improvement could be made by reducing the
aerial downlead losses, installing a high
gain aerial and by adding a low noise
masthead amplifier or signal booster.
In a small number of cases a snowy
picture can also be caused by too
strong a TV signal, customer services
will provide assistance.
‘Herringbone’ Pattern
‘Herringboning’ is generally caused by
a too strong TV signal or possibly by a
local high power transmitter such as
CB Radio, radio amateur or radio taxi.
Your TV sound may be affected as well
as the picture. Contact the Radio
Authority for further information.
‘Ghosting’
‘Ghosting’ is observed when certain
reflected signals are picked up by the
aerial in addition to the wanted direct
line of sight TV signal from the transmitter. ‘Ghosting’ will appear as
multiple pictures on your screen and is
usually caused by reflections from a
building or other tall object. If the
‘ghost’ image moves to and fro, the
problem is likely to be reflected signals
from nearby trees moving in the wind.
‘Ghosting’ can only be improved by
adjusting the height and/or position of
your aerial or by adding a aerial with a
larger reflector. ‘Ghosting’ cannot be
improved by adding a signal booster.
Co-Channel Interference
In some areas of the country and under
certain weather conditions you may
receive two programmes from different
transmitters on the same channel. This
may appear as strong horizontal lines
on the screen. TV announcements are
usually made when the effect is
persistent over a wide area. Contact
the BBC Engineering Information
Department, ITV or the Independent
Television Commission.
Electrical Interference
Interference can occur on both picture
and sound. An uneven band of spots or
RECEPTION PROBLEMS
lines indicates that the problem comes
from equipment like a vacuum cleaner,
fan or electrical drill. Try switching
the appliance off to see if the interference stops. If it does you have
located the source. All modern
household appliances are required
by law to suppress interference, so
contact the supplier of the equipment.
A burst of interference caused by the
operation of a central heating system
timeswitch or fridge/freezer switching
on and off. This may also be heard on
the sound. It may be necessary to
replace the thermostat or switch as
these sometimes deteriorate with age,
so contact an electrical supplier.
If the interference seems to be coming
from a neighbour’s house, approach
your neighbour politely. Remember
that they may be completely unaware
of the interference and that the problem could be that your set is not properly protected against interference.
Contact the Radio Authority for more
information.
Digital Terrestrial TV
Unlike analogue TV signals that can still
be viewed under weak signal strength
conditions, with digital terrestrial
signals blocking/freezing and/or loss
of digital picture and sound can be
caused by insufficient digital signal and
carrier to noise ratio. Similarly blocking
and even a completely blank screen
with no sound can result if the input
signal to the set top box is too high.
The digital cliff refers to the rapid
change from the picture and sound
being perfect to disappearing
altogether. When interconnecting
equipment and to get the best carrier
to noise then place the digital
terrestrial television set top box as the
first item in the signal path followed
by any video or satellite receiver.
Digital signals are generally immune to
ghosting or multipath reflections. They
remain perfectly receivable under
conditions where an analogue signal
would suffer ghosting. For specific help
with DTT reception problems contact
29
ONdigital and for further general
information contact the DTG Group.
To improve weak digital terrestrial
signals try the following: move the
aerial outside, reduce the aerial
downlead losses, install a high gain
aerial, add a low gain, low noise
masthead amplifier or signal booster
close to the aerial.
Analogue Satellite TV
‘Sparklies’
‘Sparklies’ or horizontal black or
white tails on screen, are generally
caused by a weak or mis-tuned signal. Examples which may cause a
weak signal include the dish moving
off-beam, problems in the coaxial
downlead, water penetration and
deterioration of the LNB. Under
severe weather such as heavy rain or
snow ‘sparklies’ may also be
experienced. Similar problems can be
caused when the receiver is not
properly tuned and locked into the
satellite channels.
Co-channel Interference
Under certain conditions co-channel
interference results because two
programmes that are on the same
frequency but from different satellites
are received simultaneously. This may
appear as a mixture of ‘sparklies’ and
vertical horizontal bars on the screen
from the unwanted satellite channel.
This is usually caused by insufficient
rejection of the unwanted satellite
due to the satellite dish being
misaligned or too small in size
resulting in it having a larger than
required reception angle.
Digital Satellite TV
With digital reception, a weak signal
or incorrectly aligned dish will cause
the picture and sound to block or disappear. Check both the alignment of
the dish and skew angle of the LNB.
Intermittent Connections
Make sure all RF cable to connector
joints are tight (both inner and outer)
including all flyleads and outlet plate
connections.
Telecoms
With the trend towards working
from home, there is an increase in
communication equipment in the
home such as telephones, fax
machines, computers and modems
to access the Internet. Multi function
machines are now available which
offer fax, copier, printer, PC-fax,
scanner and e-mail from one unit.
Telephone
There are basically four types of
telephone:
1. Analogue Corded
The traditional telephone with a fixed
cord from the phone base to the
handset.
2. Analogue Cordless
The first system of cordless technology
with limited operating distances.
3. New Frequency Analogue
Cordless
An enhanced system which uses eight
channel technology, a new frequency
range of 31-39MHz and gives clearer
call and larger operating distance
approx. 100m away from the base
station.
4. DECT-Digital Enhanced Cordless
Telephony
DECT phones that use digital cordless
technology, operate on 1.8 GHz and
allow multiple handsets to be used
from a single base station, offering significantly greater range than
analogue models, improved reception
and clearer speech.
Combined mobile/DECT cordless
phones, provide mobile and DECT
features in one smart handset, which
can accept or make calls on both
mobile and land line networks.
These use DECT protocol close
to the home and automatically
switch to mobile use outside a
certain range.
Master socket
TELECOMS & ACCESSORIES
Fax Machines
Fax machines plug into a telephone
socket and have built in software to
enable the user to transmit data for
instance a letter, which can be
received normally by another fax
machine. Early fax machines used
thermal paper but more modern
machines print directly onto standard
A4 paper.
Internet, Modem and
Interactive Services
A modem is a device which allows a
computer or Digital Set Top Box (STB)
to send and receive information over
a telephone line. It can be an internal
device built into the desktop, laptop,
or STB, a separate external box that
connects to a computer’s serial port,
or a PC card that plugs into the PC
card slot found on most laptops.
Modems are available in a variety of
speeds, the faster the modem, the
quicker the data can be transferred
and hence shorter and cheaper the
phone call will be. This is provided
the telephone line and other end of
the line can support the modem
speed and protocol.
computer to the digital line you need
an ISDN adaptor rather than a modem,
and the Internet Service Provider you
choose must offer ISDN support.
An alternative to the PC-modem-phone
line or PC-ISDN approach is to connect
through the mobile phone networks,
either by linking a laptop to a mobile
phone through a data card or an
infra-red link. Cable modems and STB
modems are often used as the return
path for the interactive services offered
by the terrestrial, satellite or cable
operators. These modems may also
offer internet access via the STB.
To connect a modem to a telephone
line the socket will need to be a BT
style socket. See following section on
BT style sockets and installing
extensions.
Faster access speeds are possible
using ISDN digital phone lines, or
services such as BT Highway which
adds a digital line alongside your
existing phone line. To connect your
Fax
Extension
telephone
Telephone
Computer
Junction
box
Extension
cable clipped
30
Telephone
double
adaptor
Telecom Accessories
Telephone Extensions
Before installing a telephone extension
it is important to note the Ring
Equivalent Number (REN). Telephones
lines have a REN of 4- they can operate
up to 4 telephone accessories
(e.g. phones, fax, answerphone) each
with a REN of 1.
An additional telephone extension
can be provided by using a multi
adaptor or by adding a new telephone
extension socket. In more complex
systems a junction box may be needed
to join up to four lengths of telephone
cable end to end.
To convert a single socket to a multi
socket outlet, Double and 3 Way
Telephone Adaptors are available.
It should be noted however, that
running more than one lead from a
single telephone socket might impair
performance of the telephone
equipment. The best option is to add
in a new telephone extension socket.
are the best way to supply a
telephone extension to another room.
Flush mounted outlets fit on a
standard 25mm deep single metal
mounting box, which is recessed into
the plaster. Alternatively they can also
be mounted on plastic surface
mounted boxes.
Extension sockets are added to the
existing telephone system from the
master socket, which is installed by
the Telephone Company such as
British Telecom (BT) or Mercury.
Extension sockets must not be used
as replacements for the existing
master socket. There are basically
two types of BT master socket:
Flush
mounted
socket
1. NTE5 socket
This type of socket is used on all new
BT installations. The lower front half is
removable to allow you to connect
extensions by ‘hard wiring’
2. Surface Mounted Extension
Sockets
If you do not have access to the walls
the most common extension socket is
a surface mounted outlet box which is
available in either a standard format
or a compact version.
2. BT ‘old’ socket
This older type of socket is the former
socket used in BT installations. You can
only connect extension sockets by
plugging in.
Telephone Flush Extension Sockets are
available with both single and twin
sockets.
Surface
mounted
socket
NTE5
socket
3
BT
‘old’ socket
4
If your telephone line is provided by
an operator other than BT, your socket
may be different to those shown
above. Contact the telecommunications operator for further information.
Extension Sockets
Types of Extension Socket
There are two basic categories of
extension socket:
1. Flush Mounted Extension Sockets
If you are installing a telephone
extension and have easy access to the
wall, flush mounted extension sockets
5
2
To connect the telephone cable into
the back of outlet sockets there are
two types of connection available
–screw terminal and IDC.
Screw terminal connections
Prepare the cable by stripping away
20-30mm of outer sleeve exposing
inner wires. Remove approximately
5mm of inner insulation to expose
bare wire. Follow the colour code.
Loosen screws, insert wires under
screws and lightly tighten ensuring
secure connections.
IDC terminal connections
Prepare the cable by stripping away
20-30mm of outer sleeve exposing
inner wires. Do not remove
inner wire
IDC
cable
connecting
tool
1
insulation. Following the colour
code, lay each wire in the
corresponding notch of the
connection terminal. Use the IDC
cable connecting tool to firmly push
the wires into the terminals.
6
Connecting Telephone Cable in
Extension Socket
When connecting telephone cable in
extension sockets the following colour
code must be observed:
1
2
3
4
5
6
N.B. It is usual to only use 2,3,4 and 5
for domestic installations.
Green/white ring
Blue/white ring
Orange/white ring
White/orange ring
White/blue ring
White/green ring
31
Connect the telephone directly into
extension socket or to extend the
distance from the socket to the
telephone, Telephone Extension
Leads are available in 2m, 4m
and 10m lengths.
USEFUL ADDRESSES
A Transmitter Guide containing TV,
Radio Transmitters, Channels and
Satellite transponders is available
from the ITC.
If you have any further questions
or other information you would like
included in a future update of this
guide, please write to the Customer
Services Department at the
address below.
Not all the products illustrated in
this guide may be available from
this retailer. However, they may be
available to special order. Ask in
store for further details.
BBC Reception Advice
Television Centre
Wood Lane, London W12 7RJ
Tel: (0870) 0100 123
e-mail: [email protected]
website: www.bbc.co.uk/info/reception
BBC Digital Radio
Room 505, Henry Wood House
Langham Place, London WC1A 1AA
Tel: (0870) 0100 300
e-mail: [email protected]
website: www.bbc.co.uk/digitalradio
NTL Engineering Information
Crawley Court, Winchester
Hampshire SO21 2QA
Tel: (01962) 823434
ITC Engineering Information
King’s Worthy Court, Winchester
Hampshire SO23 7QA
Tel: (01962) 848647
Fax: (01962) 886109
e-mail: [email protected]
website: www.itc.org.uk
The Digital Television Group
Liss Mill, Liss
Hampshire GU33 7BD
Tel: (01730) 893144
Fax: (01730) 895460
website: www.dtg.org.uk
Maxview Limited
Common Lane, Setchey, King’s
Lynn Norfolk PE33 0AT, England
Customer Helpline
Tel: (01553) 811000
Fax: (01553) 813301
e-mail: [email protected]
website: www.maxview.ltd.uk
Channel 5 Broadcasting Limited
22 Long Acre, London WC2E 9LY
Tel: (020) 7 550 5555
Fax: (020) 7 550 5554
website: www.channel5.co.uk
ONdigital
346 Queens Town Road
London SE8 4DG
Tel: (020) 7 819 8000
Fax: (020) 7 819 8100
website: www.ondigital.co.uk
Eutelsat Helpdesk
PO Box 846, Bristol BS99 5HR
Tel: (0117) 954 9191
Fax: (0117) 925 3525
website: www.eutelsat.org
British Sky Broadcasting
Grant Way, Isleworth
Middlesex TW7 5QD
Tel: (020) 7 705 3000
Fax: (020) 7 705 3030
website: www.sky.co.uk
Confederation of Aerial Industries
Fulton House Business Centre
Fulton Road, Wembley Park
Middlesex HA9 0AF
Tel: (020) 8 902 8998
Fax: (020) 8 903 8719
e-mail: [email protected]
website: www.cai.org.uk
The Radio Authority
Holbrook House
14 Great Queen Street, Holburn
London WC2B 5DG
Tel: (020) 7 430 2724
Fax: (020) 7 405 7062
website: www.radioauthority.org.uk
Arboricultural Advisory and
Information Service
Alice Holt Lodge, Wrecclesham
Nr Farnham, Surrey GU10 4LH
Tel: (01420) 22022
Fax: (01420) 22000
website: www.treeadviceservice.org.uk
Astra Marketing Limited
The Progression Centre
42 Mark Road, Hemel Hempstead
Hertfordshire HP2 7DW
Tel: (01442) 235540
Fax: (01442) 235517
website: www.astra.lu
LFTVGUIDE Iss4
32
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