Explain the working of thousand line exchanges, Computer Engineering

Assignment Help:

Explain the working of thousand line exchanges by using a combination of uniselectors and two motion selectors.

The schematic diagram for such an exchange is demonstrated in Fig. All subscribers is connected to a single rotary pre-selector switch at the exchange, and the outputs from  this switch being linked to a bank of two-motion switches termed as 'group selectors'. The outputs from the pre-selector switches of an entire group of subscribers are connected together in parallel such as group of subscribers share a single bank of group selectors. If a subscriber lifts his telephone then the cradle switch causes a circuit to be completed reverse to the telephone exchange, signaling which the subscriber wants to make a call. It is causes the pre-selector switch to step around till it find a free group selector. The pre-selector switch then stops in such position and the group selector are 'seized' through the subscriber wishing to make a call.

1166_1000 Line Exchange.png

FIG - 1000 Line Exchange

In 1000 line exchange, all subscribers have a 3 digit identification number starting from 000 to 999. By seizing the group selector, the subscriber dials his first digit and the selector switch moves up to the suitable row on the switch contact array. All final selectors have the possibility of connection to 100 lines. Therefore the 1000 lines are divided in 10 groups of 100 each, the group being specified by the first digit in the subscriber's number. Therefore the vertical motion of the group selector selects a last selector in the group related with the first digit dialed. Each single row of contacts or levels, of the group selector is associated to a bank of last selectors associated with a particular group of 100 line numbers. Containing dialed the first digit to select the suitable group, the group selector arm after that automatically rotates in the vertical direction till it finds a free last selector. In the final selector, both directions of motion are in the control of the subscriber's dial and after dialing two additional digits, connection is established, giving the called subscriber's to answer his telephone.


Related Discussions:- Explain the working of thousand line exchanges

How the simulation is done, How the simulation is done Data is entered ...

How the simulation is done Data is entered into the computer and simulation is run. The below scenarios may be tried out: -  Timing of lights varied to see how traffic flow

Define addressing modes, Define addressing modes. The dissimilar ways i...

Define addressing modes. The dissimilar ways in which the location of an operand is specified in an instruction are referred to as addressing modes.

What is referred as memory mapped i/o, What is referred as memory mapped I/...

What is referred as memory mapped I/O. The case in computers that employ only set of read and write signals and do not differentiate between memory and I/O address. This is kno

Delete command, When the user is inputting commands into your shell, it sho...

When the user is inputting commands into your shell, it should properly handle delete and backspace. When one of these characters is detected, you will need to remove one character

Limitations of experts system, 1. It is hard even for a highly skilled ex...

1. It is hard even for a highly skilled experts to abstract good situational assessment when he is under time pressure. 2. Expert systems perform well with specific t

Access to external identifiers, Access to External Identifiers: An external...

Access to External Identifiers: An external identifier is one which is referred in one module though defined in another. You can declare an identifier to be external by including i

Illustrate memory read operation, Q. Illustrate Memory Read operation? ...

Q. Illustrate Memory Read operation? Memory unit receives the address from a register known as the memory address register designated by MAR. Data is transferred to another re

Explain implementation of circuits from boolean expression, Explain Impleme...

Explain Implementation of the Circuits From the Boolean Expression? If the operation of the circuit is defined by a Boolean expression, a logic-circuit diagram can he implement

Show layout 84-key keyboards, Q. Show layout 84-key Keyboards? PC 83-ke...

Q. Show layout 84-key Keyboards? PC 83-key was the earliest keyboard provided by IBM with its first Personal Computers (PC). This had 83 keys. Afterwards IBM added one more key

Explain the term overlays, Explain the term Overlays. An overlay is an ...

Explain the term Overlays. An overlay is an element of program that has the same load origin as several other part of the program. These are used for reduce the main memory req

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd