
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. | |
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. | |
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 1.8GHz 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.
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.
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Modems are available in a variety of speeds.
The faster the modem, the quicker the data can be transferred and hence the
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.
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 computer to the digital line you need an ISDN adapter 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.

Telephone Extensions

Before installing a telephone
extension, it is important to note the Ring Equivalent Number (REN). Telephone
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. | |