- •Учреждение образования «высший государственный колледж связи» «чтение и перевод технических текстов по специальности ткс»
- •Часть II
- •Unit 3 Time Division Multiplexing
- •21.1 General definition
- •21.2 Digital time division multiplex structure
- •21.2.1 Frame organisation
- •21.2.2 Frame alignment
- •21.2.3 Signalling
- •1 Learn the words & word combinations:
- •4 Answer the questions:
- •21.3 The digital hierarchy levels
- •21.4 The t carrier framing and coding formats
- •The superframe format
- •21.4.2 The extended superframe format
- •21.4.3 Clear channels for data applications
- •1 Learn the words & word combinations:
- •4 Answer the questions:
- •21.5 The cept pcm-30 framing format
- •21.5.1 Frame composition
- •1 Learn the words & word combinations:
- •21.6.2 Error conditions
- •21.7 Coding schemes
- •1 Learn the words & word combinations:
- •4 Answer the questions:
- •Unit 4 (58) Telephones and headsets
- •58.1 Telephones
- •58.2 Telephone speech functions
- •58.3 Telephone transmitters
- •58.3.1 Carbon granule transmitter
- •58.3.2 Rocking armature transmitter
- •58.3.3 Piezoelectric transmitter
- •58.4 Telephone receivers
- •58.4.1 Rocking armature receiver
- •58.4.2 Moving coil receiver
- •1. Learn the words & word combinations:
- •4. Answer the questions:
- •5. Translate in written form point 58.3.1:
- •58.5 Telephone handset design
- •58.6 Telephone transmission performance
- •58.6.1 Sending sensitivity
- •58.6.2 Receive sensitivity
- •58.6.3 Impedance
- •58.6.4 D.C. Characteristics
- •1 Learn the words & word combinations:
- •3 Find English equivalents:
- •Answer the questions:
- •5 Translate in written form points 58.6.1 – 58.6.4:
- •58.7 Signalling
- •Incoming ringing signals
- •Outgoing 48raveling
- •Dial pulse or loop disconnect 49raveling
- •Dual tone multifrequency 50raveling
- •Loudspeaking telephones
- •1 Learn the words & word combinations:
- •4 Answer the questions:
- •5 Translate in written form points 58.9:
- •58.9 Digital telephones
- •58.10 Telephone standards
- •58.11 Headsets
- •58.12 Headset aesthetics
- •58.13 Headset technical considerations
- •58.13.1 Microphones
- •58.13.2 Earphones
- •58.14 The growing need for headsets
- •58.15 Headset approval process
- •58.16 Headset design criteria
- •1 Learn the words & word combinations:
- •Unit 5 (60) Facsimile transmission
- •60.2 Facsimile types
- •60.2.1 Photofax equipment
- •60.2.2 Weatherfax equipment
- •60.2.3 Pagefax equipment
- •60.2.4 Mobile equipment
- •60.2.5 Government and military equipment
- •60.2.5.1 Strategic requirements
- •60.2.5.2 Tactical requirements
- •60.3 Ccitt document facsimile equipment
- •1 Learn the words & word combinations:
- •3 Find English equivalents:
- •4 Answer the questions:
- •5. Translate in written form points 60.3.4:
- •60.4 G3 facsimile equipment
- •60.4.1 Scanner
- •60.4.2 Data compression
- •60.4.2.1 Modified Huffman
- •60.4.2.2 Modified read
- •60.4.3 Modulation and demodulation
- •60.4.3.1 G3 signal transmission
- •60.4.3.2 Modem operation
- •60.4.3.3 14.4Kbills option
- •1 Learn the words & word combinations:
- •2 Find Russian equivalents; mind the meaning of these expressions:
- •60.4.4.1 Ecm receiver operation
- •60.4.4.2 Ecm performance
- •60.4.5 Printer
- •60.4.6 G3 handshake protocol
- •60.5 64Kbit/s facsimile equipment
- •60.5.1 G4 equipment
- •60.5.2 64Kbit/s g3 type equipment
- •1 Learn the words & word combinations:
- •2 Find Russian equivalents; mind the meaning of these expressions:
- •3 Answer the questions:
- •5. Translate in written form points
- •60.6 G3 networks, switches, gateways and pc fax.
- •60.6.1 Managed network use
- •60.6.2 Facsimile switches
- •60.6.3 Facsimile gateways
- •60.6.4 Pc fax cards
- •60.7 Facsimile futures
- •1 Write out all the words unknown to you, learn them properly.
- •2 Translate in written form points 60.6 – 60.7
- •«Чтение и перевод технических текстов по специальности ткс»
- •Часть II
1 Learn the words & word combinations:
Principal |
Главный |
Differentiate |
Различать |
Failure |
Сбой |
Cause |
Причина, вызывать |
Slip |
Проскальзывание |
Timing problems |
Проблемы синхронизации |
Jitter |
Вибрация |
Ominous |
Зловещий |
Intermittent |
Прерывистый, механизм прерывистого действия |
Inherent |
Присущий |
Wander |
Смещение, дрейф |
2 Find Russian equivalents:
|
|
3 Find English equivalents:
|
|
4 Answer the questions:
What are the principal alarms?
What does PCM – 30 differentiate?
What is a bipolar violation?
What is a second possible T1/Е1 error condition?
What is another impairment?
What coding systems do you know?
Unit 4 (58) Telephones and headsets
PART 1 (58.1 – 58.4.2)
58.1 Telephones
When we speak our voice sets up sound vibrations which disturb the surrounding air, and travel through the air to be detected by the listener's ear drums. Sound will travel through most media, air, water, wood, plastic, etc. and at different speeds through the different media. For example in air sound travels at approximately 1100 feet per second (335m/s) and approximately 4300 feet per second in water (1311m/s). Electrical signals travel at the speed of light 3 x lrfWs.
The telephone, patented by Alexander Graham Bell in the USA in 1875-77, was an apparatus named the 'Electrical Speaking Telephone'. It was a means of transmitting sound (especially voice) over a distance, by converting sound vibrations into electrical signals which passed through wires as electrical signals, and were then reconverted to sound at the distant end. This will provide one direction of communication. In a practical telephone bothway communication is necessary, so in a simple telephone system each end is provided with means for transmitting and receiving sound.
In addition some form of mechanism is required to signal to the distant end to attract the distant party's attention to the fact that the caller wishes to talk to the distant end. Numerous forms of signalling schemes have been devised and they vary depending on the type of telephone system to which the telephone is connected. Some form of power supply is required to generate the electrical signals and many forms of circuits exist to provide power to the telephone. These consist of local batteries to power only an individual telephone or central batteries in the telephone exchange (Central Office or CO in the USA) where the power is sent down the individual telephone line to the telephone, where circuits exist to extract the power from the line and feed the telephone circuits. Cost has and is very important in telephone equipment, so the first practical telephones economised on the wiring from one telephone to the other by combining the pair of wires from the transmitter and from the receiver onto one single pair of wires, to connect both telephones together. The basic functional model for a telephone is as shown in Figure 58.1.