1 Using the text give derivatives from the following words and translate them into Russian:

to call, to speak, digit, conversation, to subscribe, to adopt, to improve, to communicate, to connect, to grow, to receive.

2 Fill the blanks using the words below:

Handset, fixed-line, crosstalk, converted, bandwidth, cable, digital, analogue, dial.

1 Optical fiber provides cheaper ….. for long distance communication.

2 Optic fibers can be bundled together in a single ….as they do not suffer from ….

3 The …. telephones in most residential homes are …..

4 Analogue signals must be … into …for transmission.

5 For internal calls, pick up the …., wait for the dial-tone, then simply …. the four numbers of the extension.

3 Answer the following questions:

1 How does an analogue telephone network operate?

2 What is the purpose of digitizing of an analogue signal?

3 What is the significance of optic fiber in development of telephone communication?

4 What are the advantages of optic fibers?

5 What are improvements in multiplexing resulted to?

4 Translate the following sentences from English into Russian:

1 In telecommunication or telephony, crosstalk is often distinguishable as pieces of speech or signaling tones leaking from other people’s connections.

2 The signals can be converted to digital form, which is much less susceptible to crosstalk.

3 Assisting communication across many modern optic fiber networks is a protocol known as Asynchronous Transfer Mode (ATM).

4 Some early implementations used coaxial cables and some recent implementations use optic fibers.

5 Where optic fiber is used, the distinction must be made between multi-mode fiber and single-mode fiber.

6 Multi-mode fiber can be thought of as thicker optical fiber that is cheaper to manufacture but that suffers from less usable bandwidth and greater attenuation.

5 Read the text, describe the principal of telephone communication

The telephone is a telecommunications device which is used to transmit and receive sound. Most telephones operate through transmission of electric signals over a complex telephone network which allows almost any phone user to communicate with almost anyone.

The telephone handles two types of information: signals and voice, at different times on the same twisted pair of wires. The signaling equipment consists of a bell to alert the user of incoming calls, and a dial to enter the phone number for outgoing calls. A calling party wishing to speak to another telephone will pick up the handset, thus operating the switch hook, which puts the telephone into active state or off hook with a resistance short across the wires, causing current to flow. The telephone exchange detects the DC current, attaches a digit receiver, and sends dial tone to indicate readiness. The user pushes the number buttons, which are connected to a tone generator inside the dial, which generates DTMF tones. The exchange connects the line to the desired line and alerts that line.

When a phone is inactive (on hook), its bell, beeper, flasher or other alerting device is connected across the line through a capacitor. The inactive phone does not short the line, thus the exchange knows it is on hook and only the bell is electrically connected. When someone calls this phone, the telephone exchange applies a high voltage pulsating signal, which causes the sound mechanism to ring, beep or otherwise alert the called party. When that user picks up the handset, the switch hook disconnects the bell, connects the voice parts of the telephone, and puts a resistance short on the line, confirming that the phone has been answered and is active. Both lines being off hook, the signaling job is complete. The parties are connected together and may converse using the voice parts of their telephones.

The voice parts of the telephone are in the handset, and consist of a transmitter (often called microphone) and a receiver. The transmitter, powered from the line, puts out an electric current which varies in response to the acoustic pressure waves produced by the voice. The resulting variations in electric current are transmitted along the telephone line to the other phone, where they are fed into the coil of the receiver, which is a miniature loudspeaker. The varying electric current in the coil causes it to move back and forth, reproducing the acoustic pressure waves of the transmitter.

When a party "hangs up" (puts the handset on the cradle), DC current ceases to flow in that line, thus signaling to the exchange switch to disconnect the telephone call.

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