Description : An automated ship-to-shore distress alerting system using satellites and advanced terrestrial communications systems. A. GPS B. Iridium system C. INMARSAT D. GMDSS
Last Answer : D. GMDSS
Description : If digitaldata rateof 9600 bps is encoded using 8-level phaseshift keying (PSK) method, the modulation rate is A. 1200 bands B. 3200 bands C. 4800 bands D. 9600 bands E. None of the above
Last Answer : 3200 bands
Description : What arethe most commonly used transmission speeds in BPS usedin datacommunication? A. 300 B. 1200 C. 2400 D. 9600 E. None of the above
Last Answer : 9600
Description : One of the first satellite system catering personal based communications services scheduled for operation. A. Iridium system B. Plutonium system C. Indium system D. Gallium system
Last Answer : A. Iridium system
Description : The approximate single-hop nighttime range of F2 layer is ____. A. 3000 km B. 3840 km C. 4130 km D. 2350km
Last Answer : C. 4130 km
Description : The probability thata singlebit will be inerror on a typical public telephone lineusing 4800 bps modem is 10 to the power -3. If no error detection mechanism is used, the residual error ratefor a communicationline using 9-bit frames is ... to A. 0.003 B. 0.009 C. 0.991 D. 0.999 E. None of the above
Last Answer : 0.009
Description : A and B entered into a partnership investing Rs. 16000 and Rs. 12000 respectively. After 3 months, A withdrew Rs. 5000 while B invested Rs. 5000 more. After 3 more months C joins the business with a capital of Rs. 21000 ... of Rs. 26400 after one year by A.Rs. 2400 B.Rs. 3600 C.Rs. 3000 D.Rs. 4800
Last Answer : Answer: B (Rs. 3600) Explanation: A:B: C = 16000 x3 + 11000×9:12000 x 3 + 17000 x 9:21000 x 6 = 147:189:126 = 7:9:6 Difference of B and C’s shares = Rs. [26400 x (9/22) — 26400 x (6/22)) = Rs. 3600.
Description : A Bunker has a leak which would empty the completely filled bunker in 20 hours. If the bunker is full of water and a tap is opened which admits 4 litres of water per minutes in the bunker, how many litres does the bunker holds? A) 2400 B) 4500 C) 4800 D) 7200
Last Answer : C Leak emptied the bunker per hour = 100/20 = 5% of water per hour; Quantity of water emptied per hour = 4*60 = 240; Thus, 5% = 240 liter; Hence, capacity of water, 100% = 240*100/5= 4800 liter.
Description : ECE Board Exam March 1996 What is the transmission rate of a system for transmitting the output of a microcomputer to a line printer operating at a speed of 30 lines/minute? Assume that the line printer has 8 bits ... and prints out 80 characters/line. A. 800 bps B. 400 bps C. 320 bps D. 640 bps
Last Answer : C. 320 bps
Description : Repeaters inside communications satellites are known as A. Trancievers B. Transponders C. Transducers D. TWT
Last Answer : B. Transponders
Description : How many characters per sec (7 bits + 1 parity ) can be transmitted over a 2400 bps line if the transfer is synchronous (1 start and 1 stop bit)?
Last Answer : 1. 300 2. 240 3. 250 4. 275 Ans- 2400/(7+1+2) 240
Description : How many characters per sec (7 bits + 1 parity) can be transmitted over a 2400 bps line if the transfer is synchronous (1 start bit and 1 stop bit)? A) 300 B) 240 C) 250 D) 275
Last Answer : How many characters per sec (7 bits + 1 parity) can be transmitted over a 2400 bps line if the transfer is synchronous (1 start bit and 1 stop bit)? 300
Description : If the bit rate for a16-QAM signal is 4000 bps, what is the baudrate? A) 300 B) 400 C) 1000 D) 1200
Last Answer : 1000
Description : If the bit rate for an FSK signal is1200 bps, thebaud rate is ________. A) 300 B) 400 C) 600 D) 1200
Last Answer : 1200
Description : f the bit rate for an ASK signal is1200 bps, thebaud rate is ________. A) 300 B) 400 C) 600 D) 1200
Description : When the elevation angle of a geostationary satellite is 23˚ and the transmitting frequency is 3840 MHz, what is the free space loss in dB? A. 196 dB B. 200 dB C. 150 dB D. 100 dB
Last Answer : A. 196 dB
Description : What is the approximate single-hop nighttime range of F2 layer? A. 3840 km B. 3000 km C. 4130 km D. 2350 km
Description : What satellite system is also known as Navstar? A. GPS B. Iridium C. Globalstar D. Intelsat
Last Answer : A. GPS
Description : What is the orbit of Motorola’s Iridium satellite system? A. Polar B. Equatorial C. Inclined elliptical D. Inclined equatorial
Last Answer : A. Polar
Description : What is considered as the most advanced satellite system developed for cellular telephones? A. Iridium B. Globalstar C. ANIK D. Molniya
Last Answer : A. Iridium
Description : Usually, it takes10-bits to represent one character. How many characters can betransmittedat a speed of 1200 BPS? A. 10 B. 12 C. 120 D. 1200 E. None of the above
Last Answer : 120
Description : A terminal multiplexer has six 1200 bps terminals and ‘n’ 300 bps terminals connected to it. If the outgoing line is 9600 bps, what is the value of n ? (A) 4 (B) 8 (C) 16 (D) 28
Last Answer : (B) 8
Description : The cutter bar of a tractor operated mower ordinarily makes: A. 800-1200 strokes/min B. 1600-2000 strokes/min C. 2400-2800 strokes/min D. 3200-3600 strokes/min
Last Answer : A. 800-1200 strokes/min
Description : One year ago the ratio between rahul salary and rohit salary is 4:5. The ratio between their individual salary of the last year and current year is 2:3 and 3:5 respectively. If the total current salary of rahul ... find the current salary of rahul. a) 1200 b) 1800 c) 2400 d) 3600 e) None of these
Last Answer : Answer: B 4x and 5x is the last year salry of rahul and rohit respectively Rahul last year to rahul current year = 2/3 Rohit last year to rohit current year = 3/5 Current of rahul + current of rohit = 4300 (3/2)*4x + (5/3)*5x = 4300. X = 300. So rahul current DDsalary = 3/2 * 4* 300 = 1800
Description : For navigation as well as marine and aeronautical communications and radar, ____ band is used. A. L B. K C. S D. J
Last Answer : A. L
Description : In satellite communications, what means of attitude control is using the angular momentum of the spinning body to provide the roll and yaw stabilization? A. Spin stabilization B. Radial stabilization C. Three-axis stabilization D. Station keeping
Last Answer : A. Spin stabilization
Description : What is the main purpose of a communications system? A. None of these B. To have a frequency assignment C. For modulation D. To provide an acceptable replica of the information at the destination
Last Answer : D. To provide an acceptable replica of the information at the destination
Description : What satellite subsystem monitors onboard conditions such as temperature and battery voltage and transmits this data back to a ground station for analysis? A. Communications subsystem B. AKM C. TTC D. Transponder
Last Answer : C. TTC
Description : In what form does the information of data communications is transmitted between two points? A. Alphanumeric form B. Alphabetic form C. Numeric form D. Binary form
Last Answer : D. Binary form
Description : In telecommunications when we call data communications it means the transmission of________. A. Voice and video B. Voice C. Video D. Computer data
Last Answer : D. Computer data
Description : Which of the following is not a common microwave application? A. Radar B. Data transmission C. Space communications D. Mobile radio
Last Answer : D. Mobile radio
Description : Rules governing the transmission of digital information. A. Line protocol B. Isochronous C. Data communications D. Digital communications
Last Answer : B. Isochronous
Description : The primary purpose of the data modem is to A. interface analog terminal equipment to analog communications channel B. interface digital terminal equipment to analog communications ... to digital communications channel D. interface digital terminal equipment to digital communications channel
Last Answer : B. interface digital terminal equipment to analog communications channel
Description : RS-232, RS-449, RS-530, V, 24 and X.21 are examples of ____________. A. standards for interfaces between modems and transmission facilities B. standards for various types of ... for interfaces between terminals and modems D. standards for end to end performance of data communications system
Last Answer : C. standards for interfaces between terminals and modems
Description : The line control unit (LCU) operates on the data digital form. A. Data communications equipment (DCE) B. UART C. Modem D. Data terminal equipment (DTE)
Last Answer : D. Data terminal equipment (DTE)
Description : A device is sending out data at the rate of 2000 bps. How long does it take to send a file of 1,00,000 characters ? a. 50 b. 200 c. 400 d. 800
Last Answer : c. 400
Description : The data rate of an FDDI system is ____________________ bps.
Last Answer : 100 M
Description : In a digital transmission, the receiver clock is 0.1 percent faster than the sender clock. How many extra bits per second does the receiver receive if the data rate is 1 Mbps ? (A) 10 bps (B) 100 bps (C) 1000 bps (D) 10000 bps
Last Answer : (C) 1000 bps
Description : An analog signal has a bit rate of 6000 bps and a baud rate of 2000 baud. How many data elements are carried by each signal element ? (A) 0.336 bits/baud (B) 3 bits/baud (C) 120,00,000 bits/baud (D) None of the above
Last Answer : (B) 3 bits/baud
Description : A device is sending out data at the rate of 2000 bps. How long does it take to send a file of 1,00,000 characters ? (A) 50 (B) 200 (C) 400 (D) 800
Last Answer : (C) 400 Explanation: 1,00,000 characters = 1,00,000 x 8 bits = 8,00,000 bits 8,00,000 bits/2000 bps = 400 seconds
Description : ECE Board Exam March 1996 The standard that specifies a balanced interface cable that will operate bit rates up to 10 Mbps with in a span distances up to 1200 m. A. RS-423A B. RS-422A C. RS-550A D. RS-449A
Last Answer : B. RS-422A
Description : What was the major operational limitation of early communications satellites?
Last Answer : The lack of suitable power sources.
Description : What are the two types of communications satellites?
Last Answer : Passive and active.
Description : Who propounded the possibility of placing communications satellites in geosynchronous orbit for the first time ? (1) Edwin P. Hubble (2) William Herschel (3) Arthur C. Clarke (4) Pierre Laplace
Last Answer : Arthur C. Clarke
Description : The wavelength of visible light extends from a. 0.8 to 1.0 nm b. 400 to 750 nm c. 200 to 660 nm d. 700 to 1200 nm
Last Answer : b. 400 to 750 nm
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 : Geostationary stationary satellites are located ___________ with respect to the equator. A. 0˚longitude B. 0˚ latitude C. 90˚latitude D. 45 latitude˚
Last Answer : B. 0˚ latitude
Description : Most satellites operate in which frequency band? A. 30 to 300 MHz B. 300 MHz to 3 GHz C. 3 GHz to 30 GHz D. Above 300 GHz
Last Answer : C. 3 GHz to 30 GHz
Description : What kind of battery used by older satellites? A. Lithium B. Leclanche C. Hydrogen D. Magnesium
Last Answer : C. Hydrogen
Description : What is the orbit inclination of geostationary satellites? A. 0° B. 10° C. 20° D. 30°
Last Answer : A. 0°