The CCITT standard bandwidth for speech is:
 (A) 20000 Hz (B) 15000 Hz
 (C) 7000 Hz (D) 3400 Hz

1 Answer

Answer :

(D) 3400 Hz

Related questions

Description : What is the reference frequency of CCITT psophometric noise measurement? A. 800 Hz B. 1500 Hz C. 3400 Hz D. 1000 Hz

Last Answer : A. 800 Hz

Description : Two persons Ashok and Amit enter into a business. Ashok invests Rs 12500 in the first time and after 6months withdraws Rs 7000. Amit withdraws Rs 3000 after 8 months. Both have equal profit at the end of the year. What is the amount invested by Amit initially? A) 15000 B) 20000 C) 10000 D) 16000

Last Answer : Answer: C)  Ashok’s investment =12500*6+5500*6=108000  Amit’s investment=x*8+(x-3000)*4  108000=8x+4x-12000=>X=Rs 10000  Amount invest by Amit is Rs 10,000

Description : What is the channel bandwidth of a standard analogue telephone system? A. 300-500 Hz B. 1200 kHz C. 100-300 Hz D. 300-3400 Hz

Last Answer : D. 300-3400 Hz

Description : Explain FDM and show how CCITT standards help in building the base band?

Last Answer : Frequency Division Multiplexing: It is the process of combining several information channels by shifting their signals to different frequency groups within the spectrum so that they can be transmitted simultaneously ... of 24 channels were assembled together in one stage of modulation.     

Description : Explain the CCITT hierarchical structure of switching and routing using block schematic.

Last Answer : Hierarchical network are capable of handing heavy traffic where required, and at the same time use minimal number of trunk groups. A 5-level switching hierarchy is recommended by CCITT as ... A strictly hierarchical network suffers from serious drawback i.e. its poor fault tolerance future.

Description : The bandwidth requirement of a telephone channel is (A) 3 KHz (B) 15 KHz (C) 5 KHz (D) 25 KHz

Last Answer : (A) 3 KHz

Description : In a DTMF phone a dialling of 8 generates (A) 1336 Hz- 770 Hz (B) 1209 Hz - 1477 Hz (C) 1209 Hz- 941 Hz (D) 1336 Hz-852 Hz

Last Answer : (D) 1336 Hz-852 Hz

Description : How speech is transmitted in a digital switching environment using PCM/TDM?

Last Answer : A digital carrier system is a communications system that uses digital pulses rather than analogue signals to encode information. Fig shows the block diagram for a digital carrier system. This digital ... to maintain frame and sample synchronization between the TDM transmitter and receiver. 

Description : SS7 Protocol uses: (A) Out of band signalling. (B) Associated signalling. (C) Speech control signalling. (D) No signalling.

Last Answer : (A) Out of band signalling.

Description : Common channel signalling in SS7 is (A) out band control channel. (B) in band control channel. (C) speech control channel. (D) none of the above.

Last Answer : (B) in band control channel.

Description : Side tone is the speech heard by (A) the receiving subscriber (B) both the receiving and calling subscriber (C) by on looker (D) by calling subscriber

Last Answer : (D) by calling subscriber

Description : ISDN handles data pertaining to (A) All digital services (B) Speech and Video (C) Computer data only (D) Speech only

Last Answer : (A) All digital services

Description : In a time multiplexed space switching system, one speech sample appears every (A) 125 micro sec (B) 20 msec (C) 125 msec (D) 1 sec

Last Answer : (A) 125 micro sec

Description : Common channel signalling______________ (A) Uses the speech or data path for signaling. (B) Does not use the speech or data path for signaling. (C) Needs no additional transmission facilities. (D) Finds it difficult to handle signaling during speech.

Last Answer : (C) Needs no additional transmission facilities.

Description : The ratio of income of X and Y is 4:3. The sum of their expenditure is Rs.12,000 and the amount of savings is X is equal to the amount of expenditure of Y.What is the salary of Y? A) 9000 B) 7000 C) 12000 D) 15000 E) None of these

Last Answer : Answer: A X’s saving = Expenditure of Y = S 4x-S + S = 12000 X = 3000 3x =3*3000 = 9000

Description : Write the command using Insert() function to add a new column in the last place(3rd place) named “Salary” from the list Sal=[10000,15000,20000] -Technology

Last Answer : EMP.insert(loc=3,column=”Salary”,value=Sal)

Description : If the fixed costs of a factory producing candles is Rs 20,000, selling price is Rs 30 per dozen candles and variable cost is Rs 1.5 per candle, what is the break-even quantity? (1) 20000 (2) 10000 (3) 15000 (4) 12000

Last Answer : (1) 20000 Explanation: Breakeven quantity is the number of incremental units that the firm needs to sell to cover the cost of a marketing program or other type of investment. It is given by the formula: BEQ = FC / (P-VC) Where ... per unit = 30/12 = Rs. 2.5 So 20000/ (2.5-1.5) = 20000/1= Rs. 20,000

Description : The min RPLI policy limit is a) 20000/- b) 25000/- c) 10000/- c) 15000/

Last Answer : c) 10000/

Description : Company registration fee for small scale industry is Rs ……………… A. 10000 C. 15000 B. 25000 D. 20000

Last Answer : 25000

Description : 6000 ÷ 15 × 225 – 70000 = ? a) 20000 b) 18000 c) 16000 d) 14000 e) 15000

Last Answer : ? = 6000 – 225 / 15 - 70000 = 90000 – 70000 = 20000 Answer: a)

Description : Salaries Rs.20000,depreciation for the period is Rs.30000 other operating expenses are Rs.9000, net loss for the period is Rs.5000 fund generated from operation is------------------ a) Rs.25000 b) Rs.15000 c) Rs.35000 d) Rs.14000

Last Answer : a) Rs.25000

Description : If the fixed costs of a factory producing candles is Rs 20,000, selling price is Rs 30 per dozen candles and variable cost is Rs 1.5 per candle, what is the break-even quantity? (1) 20000 (2) 10000 (3) 15000 (4) 12000

Last Answer : 20000

Description : SPC stands (A) Standard Protocol Control (B) Stored Program Control (C) Signaling and switching Centre (D) Signaling Process Center

Last Answer : (B) Stored Program Control

Description : What is the reference frequency of CCIT phosphomeric noise measurement? A. 800 Hz B. 1000 Hz C. 1500 Hz D. 3400 Hz

Last Answer : A. 800 Hz

Description : ECE Board Exam March 1996 The number of voice band channels in master group per CCITT standard is __________. A. 300 B. 480 C. 600 D. 12

Last Answer : A. 300

Description : What are audible sound waves? (1) Having frequency less than 20 Hz (2) Having frequency between 20 Hz to 20000 Hz (3) Having frequency more than 20000 Hz (4) None of above

Last Answer : (2) Having frequency between 20 Hz to 20000 Hz

Description : Man perceives sound vibrations in the frequency ranges of – (1) 0 – 5 Hz (2) 6 - 10 Hz (3) 11 - 15 Hz (4) 20 - 20000 Hz

Last Answer : (4) 20 - 20000 Hz Explanation: The frequencies at which a human being can perceive sound vary between 20 Hertz and 20,000 Hertz. It is within these frequency ranges that people can communicate to each other and listen to music.

Description : The term "infrasonic" applied to sound refers to sound waves below - (1) 200 Hz (2) 20000 Hz (3) 20 Hz (4) 0 Hz

Last Answer : (3) 20 Hz Explanation: The term "infrasonic" applied to sound refers to sound waves below the frequencies of audible sound, and nominally includes anything under 20Hz.

Description : A carrier signal has ______. A. Constant peak amplitude B. The information C. Frequency range 20-20000 Hz D. A varying amplitude

Last Answer : A. Constant peak amplitude

Description : Man perceives sound vibrations in the frequency ranges of (1) 0 – 5 Hz (2) 6 – 10 Hz (3) 11 – 15 Hz (4) 20 – 20000 Hz

Last Answer :  20 – 20000 Hz

Description : What do you mean by numbering and addressing? Draw the ISDN address structure and explain how the addressing works?

Last Answer :  Numbering and Addressing: In telephone and data networks, the end equipments are more often single units than multiple devices units like PABX or LAN. Historically, a telephone, a computer, or a ... as reference point may also be addressed by using direct inward dialing (DID) feature.  

Description : Explain the process of inter-register signalling.

Last Answer : Registers are used in common control exchanges to store and analyze routing data. They are provided on a common basis is a single register provides routing data for a number of speech circuits. Once a call ... it is released and the originating register signals to the next register.

Description : Draw a centralized SPC organization and explain how it works under load sharing operation.

Last Answer : In centralized control, all the control equipment is replaced by a single processor which must be quite powerful. It must be capable of processing 10 to 100 calls per second, depending on the ... both the processors are active simultaneously and share the load and the resources dynamically.  

Description : What are transmission bridges? How do they help in satisfying the connectivity?

Last Answer : A typical transmission bridge is shown in Fig. The series capacitance and the shunt inductances of the two relays provide a high-pass filter to transmit the AC speech signals, while the relays respond independently to the DC loop/disconnect signals from the calling and called customer.  

Description : What are the different ways of designing 100 line exchange using uni selector and two motion selectors? Show at least three variations. Which is the best option?

Last Answer : Here three different designing methods for 100 line exchange are discussed: Design 1: Here, Strowger switching system is designed using one two-motion selector for each subscriber. A ... only under certain specific traffic conditions and generally lead to higher blocking probabilities.  

Description : How numbering plan is achieved in modern telephony? Give the structure with example.

Last Answer :  The objective of numbering plan is to uniquely identify every subscriber connected to a telecommunication network. A numbering plan may be open, semiopen or closed. An open-numbering plan permits wide ... known as the subscriber number which is the number listed in the telephone directory.   

Description : How does a touch tone receiver differs from pulsed dial receiver? Explain with schematic.

Last Answer : Pulse dialing: 1. Generated through make and break contact. 2. DC Current pulse is generated. 3. Each number is separated by a short pause to prevent overlapping. 4. Codes ... dialing pulse is not misinterpreted as the phone being returned to its on-hook (idle) condition.   

Description : Discuss different Routing plan adopted in a Telephone network.

Last Answer : Hierarchical networks are capable of handing heavy traffic where required, and at the same time use minimal number of trunk groups. Three methods are used for deciding on the route for a ... selection methods can be implemented. Computer based routing is a standard feature in data networks.  

Description : Discuss briefly subscriber loop system. Give some technical specification for subscriber lines.

Last Answer : Subscriber Loop System: Every subscriber in a telephone network is connected generally to the nearest switching office by means of a dedicated pair of wires. Subscriber loop refers to this pair of wires. It is un ... 1. Diameter of wire 2. D.C. resistance per Km 3. Attenuation per Km 

Description : What is Traffic Engineering? Define the term busy hour, traffic intensity and grade of service.

Last Answer : Traffic engineering provides the basis for analysis and design of telecommunication network to carry a given traffic at a particular loss probability. It provides a means to determine the quantum of common equipments ... A0  Where  A= offered traffic  A0 = carried traffic  A-A0= lost traffic    

Description : Explain topology method used in LAN technology in detail.

Last Answer : LAN Topologies: Network topology is a physical schematic which shows interconnection of the many users. There are four basic topologies as under: (i) Direct Connection or one to all topology ( ... temporarily, inserting the new node and then reestablishing the complete ring path.

Description : List all seven layer of OSI model and describe function of application layer.

Last Answer : The layers of OSI model are as follows:  (1) The Physical Layer: This defines an interface in terms of the connections, voltage levels and data rate, in order for signals to ... with the applications programs needed. Examples include electronic mail, word processing, banking transactions, etc.  

Description : Find the total number of link L having five entities? Explain differences between folded and non-folded network.

Last Answer : Folded network: When all the inlets/outlets are connected to the subscriber lines, the logical connection appears as shown in Fig. In this case, the output lines are folded back to the input ... non-folded network to be non-blocking, the network should support N simultaneous switching paths.  

Description : Explain simple telephone communication system with circuit and equation of current flow in microphone?

Last Answer : Simple Telephone Communication: In the simplest form of a telephone circuit, there is one way communication involving two entities, one receiving (listening) and the other transmitting (talking).   ... carrier wave in AM system. The quantity m is equivalent to the modulation index in AM. 

Description : Explain crossbar exchange, with all call processing steps and diagrams

Last Answer : The basic idea of crossbar switching is to provide a matrix of n x m sets of contacts with only n + m activators or less to select one of the n x m sets of contacts. This form of ... a contact is established at the cross point 6 such that the subscriber B is connected to the subscriber C. 

Description : What are the advantages and disadvantages of packet switching over circuit switching?

Last Answer : The comparison of packet switching and circuit switching showing advantages and disadvantages of packet switching over circuit switching is given below:

Description : What is a Modem? What is the need of MODEM in data communication? Explain at least one modulation technique used for high speed modems.

Last Answer : Modems are essentially used to interface digital circuits to transmit information on analogue channels like telephone systems. Modem (from modulator-demodulator) is a device that modulates an analogue carrier ... caused by the lines makes the detection even harder than amplitude modulation.   

Description : What are the advantages of CCS over in-channel signalling?

Last Answer : The advantages of CCS over in-channel signalling are listed below: a. Information can be exchange between the processors much more rapidly than when channel associated signaling is used. b ... for functions other than call processing, for example for maintenance or network management purposes. 

Description : Through two block diagrams explain the difference between Space division and time division switching.

Last Answer :  Space and Time Switching: Space Switches: Connections can be made between incoming and outgoing PCM highways by means of a cross point matrix of the form shown in Fig. However, different channels of ... of the speech store, whose contents are read out and sent over the outgoing highway.  

Description : Show how finite state machine model helps in designing a switching system and give a typical example.

Last Answer : Switching system basically belongs to the class of finite state machines (FSM) which are asynchronous in nature and follows a sequential logic for their operation. They can be modeled by ... circuits and memory elements. Clocked synchronous operation shown in Fig. overcome such problems.