A. shunt capacitance capacitance B. series series capa capacit citan ance ce C. indu induct ctan ance ce D. resi resist stan ance ce Answer & Explanation Explanation Answer: Answer: Option A
A. frequenc+ frequenc+ ad,ustment ad,ustment B. frequ frequen enc+ c+ interle interlea*i a*ing ng C. frequ frequen enc+ c+ chang changing ing D. frequen frequenc+ c+ amalgam amalgamatio ation n Answer & Explanation Explanation Answer: Answer: Option B
A modem is classified classified as low speed if data rate handled is
-n F signal with a modulation index mf is passed through a frequenc+ tripler. )he wa*e in the output of the tripler will ha*e a modulation index of
A. upto !! "ps B. upto upto #$! #$! "ps "ps C. upto upto %!! %!! "ps "ps D. upto upto !! !! "ps "ps Answer & Explanation Explanation Answer: Answer: Option D
A. mf B. /mf C. mf0/ D. mf01 Answer & Explanation Explanation Answer: Answer: Option B
'(B modulation is preferred in )' "ecause
-n colour )' recei*er2 *aractor diode is used for
A. it reduces the "andwidth "andwidth requiremen requirementt to half B. it a*oids a*oids phase phase distor distortion tion at low low frequencies C. it results results in "ette "etterr recepti reception on D. none none of of the the a"o* a"o*e e Answer & Explanation Explanation Answer: Answer: Option A
A. detection detection B. rect rectif ific icat atio ion n C. tuning D. "oth "oth 3a4 3a4 and and 3"4 3"4 Answer & Explanation Explanation Answer: Answer: Option C
A woofer should "e "e fed from from the input input through a A. low pass filter B. high high pas pass s filt filter er C. "and "and pass pass filter filter D. "and "and sto stop p fil filter ter Answer & Explanation Explanation Answer: Answer: Option A he colour su"carrier and side"ands produced "+ its modulation with the chrominance signals are accommodated
)he num"er of noise sources in a B5) are A. / B. # C. D. % Answer & Explanation Explanation Answer: Answer: Option A
Energ+ content of atmospheric noise A. does not not depend on frequenc+ frequenc+ B. decreas decreases es as freque frequenc+ nc+ is increa increased sed C. increas increases es as frequen frequenc+ c+ is increas increased ed D. either either 3a4 or or 3c4 depen dependin ding g on the the temperature
Answer & Explanation Answer: Option B
Answer & Explanation Answer: Option D
A %!! 6 carrier is amplitude modulated with m 7 !.8$. )he total power in A is
Assertion 3A4: Free space does not interfere with normal radiation and propagation of radio wa*es
A. %!! 6 B. $# 6 C. $99 6 D. $! 6 Answer & Explanation Answer: Option B c3t4 and m3t4 are used to generate an F signal. -f the pea frequenc+ de*iation of the generated F signal is three times the transmission "andwidth of the A signal2 then the coefficient of the term cos ;#p3!!9 x !/t4< in the F signal 3in terms of the Bessel Coefficients4 is A. $ 5%3/4 B. 593/4 C. 593%4 D. $ 5%34 Answer & Explanation Answer: Option D =on>coherentl+ detection is not possi"le for A. ?(@ B. A(@ C. F(@ D. "oth 3a4 and 3c4 Answer & Explanation Answer: Option A
eason 34: Free space has no magnetic or gra*itational fields. A. Both A and are correct and is correct explanation of A B. Both A and are correct "ut is not correct explanation of A C. A is correct "ut is wrong D. A is wrong "ut is correct Answer & Explanation Answer: Option A -n radar s+stems ?F stands for A. ?ower eturn Factor B. ?ulse eturn Factor C. ?ulse epetition Frequenc+ D. ?ulse esponse Factor Answer & Explanation Answer: Option C
6hich of the following cannot "e the Fourier series expansion of a periodic signal A. x3t4 7 # cos t / cos /t B. x3t4 7 # cos pt 8 cos t C. x3t4 7 cos t !.$ D. x3t4 7 # cos .$pt sin /.$ pt Answer & Explanation Answer: Option C
)racing of extra terrestrial o",ects requires A. B. C. D.
high transmitting power *er+ sensiti*e recei*er full+ steera"le antenna all of the a"o*e
6hich of the following is the indirect wa+ of F generation A. eactance "ipolar transistor modulator B. Armstrong modulator
C. 'aractor diode modulator D. eactance F modulator Answer & Explanation Answer: Option B
Answer & Explanation Answer: Option D
A telephone exchange has 1!!! su"scri"ers. -f the num"er of calls originating at pea time is !2 !!! in one hour2 the calling rate is
A. !!! m B. $!! m C. !! m D. ! m Answer & Explanation Answer: Option C
A. !.1B. !01 C. !.9 D. !. Answer & Explanation Answer: Option B -f C is capacit+ of nois+ channel2 3"its0s42 f is "andwidth and (0= is signal to noise ratio2 then A. B. C. D. Answer & Explanation Answer: Option A
As the frequenc+ increases2 the a"sorption of ground wa*e "+ earthGs surface
)he range of a cordless telephone is a"out
An earth mat for a communication tower consists of A. one or two radials extending from "ase of tower at a depth of a"out $ cm "elow ground B. a large num"er of radials extending from "ase of tower at a depth of a"out / m C. a large num"er of radials extending from "ase of tower at a depth of a"out /! cm D. none of the a"o*e Answer & Explanation Answer: Option C
Degaussing in a picture tu"e means A. decreases B. increases C. remains the same D. either 3a4 or 3c4 Answer & Explanation Answer: Option B )he *elocit+ of sound wa*es in air A. is constant at all temperatures B. *aries directl+ as temperature C. *aries in*ersel+ as a"solute temperature D. *aries directl+ as square root of a"solute temperature
A. Adding magnetism in mas and mounting frame B. emo*ing residual magnetism in mas2 shield etc... C. -ncreasing resistance of coils to decrease time constant D. Decreasing resistance of coils to increase time constant. Answer & Explanation Answer: Option B )he rate at which information can "e carried through a communication channel depends on
A. carrier frequenc+ B. "andwidth C. transmission loss D. transmitted power Answer & Explanation Answer: Option B
C. 111.# D. 119.! Answer & Explanation Answer: Option B Explanation: Frequenc+ present in the side"ands is equal to 7 fc H fm2 fc H #fm 2 fc H /fm .
(ome t+pes of traps used in *ideo -F amplifier of colour )' are A. shunt traps B. series traps C. a"sorption traps D. all of the a"o*e Answer & Explanation Answer: Option D
Direct and reflected sound wa*es ma+ interfere with each other. A. )rue B. False Answer & Explanation Answer: Option B
A carrier is simultaneousl+ modulated "+ two sine wa*es ha*ing modulation indices of !.% and !./. )he total modulation index will "e A. !.B. !.8 C. !.$ D. !./$ Answer & Explanation Answer: Option C
A !!! carrier is simultaneousl+ modulated with /!! 2 9!! and # audio sine wa*es. 6hich of the following frequenc+ is least liel+ to "e present in the output A. !!# B. !!!
-n standing wa*e pattern on a transmission line A. *oltage and current nodes coincide B. *oltage and current antinodes coincide C. *oltage nodes and current antinodes as well as current nodes and *oltage antinodes coincide D. "oth 3a4 and 3"4 Answer & Explanation Answer: Option C
-f the "andwidth is increased "+ #2 the IF IA 3where I is the ratio of (= of output to (= at input2 F is frequenc+ modulation and A is amplitude modulation4 is increased "+ a factor of A. # B. / C. % D. Answer & Explanation Answer: Option C Explanation: Dou"ling of frequenc+ increase (= in frequenc+ modulation "+ %. -t has no effect in A. A carrier wa*e carries information. A. )rue B. False Answer & Explanation Answer: Option B
3# ms4 3 > !.!%4 7 .1# ms. Frequenc+ shift e+ing is used mostl+ in Consider the following statements A. telegraph+ B. telephon+ C. satellite communication D. radio transmission Answer & Explanation Answer: Option A -t is desired that transmission line and load should match for a range of frequencies. )he "est method is A. to use a "alun B. to use a single stu" of ad,usta"le position C. to use a dou"le stu" D. to use a "road "and amplifier Answer & Explanation Answer: Option C
6hich of the following has the highest input impedance A. CE B. CB C. CC D. ?ush pull Answer & Explanation Answer: Option C -n a fascimile reproduction time to scan one line is # ms. -f it has %J "laning2 the *isi"le trace time is A. .1# ms B. #.!9 ms C. $! ms D. !.!9 ms Answer & Explanation Answer: Option A Explanation:
)he amplitude of an F wa*e is constant F is more immune to noise than A F "roadcasts operate in upper 'F and KF frequenc+ ranges F transmitting and recei*ing equipments are simpler as compared to A transmitting and recei*ing equipments 6hich of the a"o*e are correct A. 2 #2 /2 % B. 2 #2 / C. #2 /2 % D. 2 /2 % Answer & Explanation Answer: Option B (ignal to noise ratio of microphone is defined as the ratio of output when the sound pressure is LLLLLLLLLL to the output in the a"sence of an+ sound signal. A. !.$ ?a B. !.# ?a C. !. ?a D. !.! ?a Answer & Explanation Answer: Option C Explanation: !. ?a 37 !.$ x !>% 60m#4 is taen as standard sound pressure for defining (0= ratio of microphones. A generator is feeding power to a transmission line of characteristic impedance M!. )he line is terminated in impedance MN. (tanding wa*es will "e set up if
A. MN 7 M! B. MN M! C. MN P M! D. "oth 3"4 and 3c4 Answer & Explanation Answer: Option D
Frequenc+ modulation gi*es noise free reception and is used for radio "roadcasts.
-n sound recording the degree of pre> emphasis is a"out dB0 octa*e. A. )rue B. False Answer & Explanation Answer: Option B
A. #! secs B. # secs C. !.# secs D. !.!$ secs Answer & Explanation Answer: Option D
Explanation:
Explanation:
-t erases the matter alread+ existing on the tape.
6hich of the following is taen as reference antenna for directi*e gain
(pace wa*e ma+ "e a direct wa*e or wa*e reflected from earth.
A. alf wa*e dipole B. Elementar+ dou"let C. -sotropic D. -nfinitesimal dipole Answer & Explanation Answer: Option C
A. )rue B. False Answer & Explanation Answer: Option B
-f the frequenc+ of a wa*e #! 2 the time period is
Explanation: Counterpoise is used in coils ha*ing (trength of space wa*e depends on distance as it suffers attenuation. adio "roadcasts are generall+ A. amplitude modulation B. frequenc+ modulation C. "oth amplitude and frequenc+ modulation D. neither amplitude nor frequenc+ modulation Answer & Explanation Answer: Option B Explanation:
A. high resisti*it+ B. low resisti*it+ C. medium resisti*it+ D. "oth 3"4 and 3c4 Answer & Explanation Answer: Option A -n CC->B s+stem2 the time "etween start of one s+n. pulse and next is A. % Qs B. .% Qs C. %! Qs D. !.% Qs Answer & Explanation Answer: Option A
6hen the channel is nois+2 producing a conditional pro"a"ilit+ of error p 7 !.$R the channel capacit+ and entrop+ function would "e2 respecti*el+2 A. and B. and !.$ C. !.$ and D. ! and Answer & Explanation Answer: Option D
?ush pull amplifier is A. *oltage amplifier B. current amplifier C. power amplifier D. none of the a"o*e Answer & Explanation Answer: Option C
