CBSE Class 12 Operation and Maintenance of Communication Devices Question Paper 2019

SET-4
Series BVM H$moS> Z§.
Code No. 313
amob Z§.
Roll No. narjmWu H$moS >H$mo CÎma-nwpñVH$m Ho$ _wI-n¥ð
>na Adí` {bIo§ &
Candidates must write the Code on the
title page of the answer-book.

 H¥$n`m Om±M H$a b| {H$ Bg àíZ-nÌ _o§ _w{ÐV n¥ð> 8 h¢ &
 àíZ-nÌ _| Xm{hZo hmW H$s Amoa {XE JE H$moS >Zå~a H$mo N>mÌ CÎma -nwpñVH$m Ho$ _wI-n¥ð> na
{bI| &
 H¥$n`m Om±M H$a b| {H$ Bg àíZ-nÌ _| >31 àíZ h¢ &
 H¥$n`m àíZ H$m CÎma {bIZm ewê$ H$aZo go nhbo, àíZ H$m H«$_m§H$ Adí` {bI| &
 Bg àíZ-nÌ H$mo n‹T>Zo Ho$ {bE 15 {_ZQ >H$m g_` {X`m J`m h¡ & àíZ-nÌ H$m {dVaU nydm©•
_| 10.15 ~Oo {H$`m OmEJm & 10.15 ~Oo go 10.30 ~Oo VH$ N>mÌ Ho$db àíZ-nÌ H$mo n‹T>|Jo
Am¡a Bg Ad{Y Ho$ Xm¡amZ do CÎma-nwpñVH$m na H$moB© CÎma Zht {bI|Jo &
 Please check that this question paper contains 8 printed pages.
 Code number given on the right hand side of the question paper should be
written on the title page of the answer-book by the candidate.
 Please check that this question paper contains 31 questions.
 Please write down the Serial Number of the question before
attempting it.
 15 minute time has been allotted to read this question paper. The question
paper will be distributed at 10.15 a.m. From 10.15 a.m. to 10.30 a.m., the
students will read the question paper only and will not write any answer on
the answer-book during this period.

g§Mma CnH$aUm| H$m g§MmbZ Am¡a aIaImd
OPERATION AND MAINTENANCE OF
COMMUNICATION DEVICES
{ZYm©[aV g_` : 2 12 KÊQ>o A{YH$V_ A§H$ : 50
1
Time allowed : 2 hours Maximum Marks : 50
2
313 1 P.T.O.

gm_mÝ` {ZX}e :
(i) Bg àíZ-nÌ _| 31 àíZ em{_b h¢ {OZ_| go Aä`Wu H$mo {g\©$ 23 àíZ H$aZo H$s Oê$aV
h¡ &
(ii) àíZ-nÌ Xmo IÊS>m| _| {d^º$ h¡ &
IÊS> A
(H$) ~hþ{dH$ënr` àíZ /[aº ñWmZ ^[aE /grYo àíZ : Hw$b 12 àíZ em{_b h¢ Omo
1 – 1 A§H$ Ho$ h¢ & BZ_| go {H$Ýht 10 àíZm| Ho$ CÎma Xr{OE &

(I) A{V bKw CÎmar` àíZ : BZ_| Hw$b 7 àíZ em{_b h¢ & àË`oH$ Ho$ 2 A§H$ h¢ & BZ_|
go {H$Ýht 5 àíZm| Ho$ CÎma Xr{OE &
(J$) bKw CÎmar` àíZ : BZ_| Hw$b 7 àíZ em{_b h¢ & àË`oH$ Ho$ 3 A§H$ h¢ & BZ_| go
{H$Ýht 5 àíZm| Ho$ CÎma Xr{OE &
IÊS> ~
XrK© CÎmar` /{Z~ÝYmË_H$ àíZ : BZ_| Hw$b 5 àíZ em{_b h¢ & àË`oH$ Ho$ 5 A§H$ h¢ & BZ_|
go {H$Ýht 3 àíZm| Ho$ CÎma Xr{OE &
General Instructions :

(i) This question paper contains 31 questions out of which the candidate
needs to attempt only 23 questions.

(ii) Question paper is divided into two sections.

SECTION A

(a) Multiple choice questions / Fill in the blanks/Direct questions :
contains total 12 question of 1 mark each. Answer any
10 questions.

(b) Very short answer type questions : contains total 7 questions of
2 marks each. Answer any 5 questions.

(c) Short answer type questions : contains total 7 questions of 3 marks
each. Answer any 5 questions.

SECTION B

Long answer / Essay type questions : contains total 5 questions of 5 marks
each. Answer any 3 questions.

313 2

IÊS> A$
SECTION A

{H$Ýht Xg àíZm| Ho$ CÎma Xr{OE & àË`oH$ àíZ EH$ A§H$ H$m h¡ & 110=10
Attempt any ten questions. Each question carries 1 mark.

1. _m°Sw>{bV Va§J Amd¥{Îm h¡
(H$) dmhH$ Amd¥{Îm go Cƒ
(I) dmhH$ Amd¥{Îm go H$_
(J) dmhH$ Amd¥{Îm Ho$ ~am~a
(K) H$moB© _yë` hmo gH$Vm h¡
Modulating frequency is
(a) Higher than carrier frequency
(b) Lower than carrier frequency
(c) Equal to carrier frequency
(d) Can have any value

2. _wº$ ñWmZ _|, {dÚwV²-Mwå~H$s` Va§Jm| H$s J{V h¡
(H$) 300 _rQ>a/goH§$S>
(I) 3  104 _rQ>a/goH§$S>
(J) 1  10 _rQ>a/goH§$S>
(K) 3  108 _rQ>a/goH§$S>
In free space, the speed of electromagnetic waves is
(a) 300 metres/second
(b) 3  104 metres/second
(c) 1  10 metres/second
(d) 3  108 metres/second

3. dr.EM.E\$. g§Ho$V __________ Ho$ _mÜ`_ go g§MaU H$aVo h¢ &
(H$) Am`Z_§S>b
(I) jmo^_§S>b
(J) n¥Ïdr H$s gVh
(K) Va§J nWH$
VHF signals propagate through
(a) Ionosphere
(b) Troposphere
(c) Surface of the earth
(d) Waveguide
313 3 P.T.O.

4. gobwba _mo~mBb {gñQ>_ _|, gob H$m AmH$ma hmoVm h¡
(H$) d¥ÎmmH$ma
(I) hoŠgmJmoZb
(J) n|Q>mJZ
(K) Am`VmH$ma
In a cellular mobile system, the shape of the cells is
(a) Circular
(b) Hexagonal
(c) Pentagon
(d) Rectangular

5. EH$ ^yJ^u` CnJ«h AnZr H$jm Ho$ EH$ Xm¡a (M¸$a) _| boVm h¡
(H$) EH$ K§Q>m
(I) Mma K§Q>o
(J) ~mah K§Q>o
(K) Mm¡~rg K§Q>o
A geostationary satellite takes one round of its orbit in
(a) One hour
(b) Four hours
(c) Twelve hours
(d) Twenty-four hours

6. CnJ«h àUmbr _| {dÚwV² e{º$ H$m òmoV h¡
(H$) ~¡Q>ar gob
(I) OZaoQ>a
(J) gm¡a n¡Zb
(K) BªYZ H$mo{eH$mE±
The source of electrical power in a satellite system is
(a) Battery Cells
(b) Generators
(c) Solar Panels
(d) Fuel Cells

313 4

7. _mo~mBb g§Mma _|, h_ 1Or, 2Or, 3Or Am¡a 4Or H$m Cn`moJ H$aVo h¢ & `hm± Or (G)
à{V{Z{YËd H$aVm h¡
(H$) gaH$ma
(I) d¡pídH$
(J) OZaoeZ
(K) JoQ>do
In mobile communication, we use 1G, 2G, 3G and 4G. Here G represents
(a) Government
(b) Global
(c) Generation
(d) Gateway

8. {ZåZ{b{IV _| go H$m¡Z-gm _mo~mBb \$moZ H$m KQ>H$ Zht h¡ ?
(H$) dº$m
(I) S>mBnmob (Dipole)
(J) Eb.gr.S>r. _m°S>çyb
(K) ~¢S>nmg {µ\$ëQ>a
Which of the following is not a mobile phone component ?
(a) Speaker
(b) Dipole
(c) LCD Module
(d) Bandpass Filter

9. ãbyQy>W àm¡Úmo{JH$s H$mo ___________ Ho$ {bE g§Mma _| à`moJ {H$`m OmVm h¡ &
(H$) b§~r Xÿar
(I) N>moQ>r Xÿar
(J) Am°pßQ>H$b
(K) ñH¡$qZJ
Bluetooth technology is used in communication for
(a) Long distance
(b) Short distance
(c) Optical
(d) Scanning
313 5 P.T.O.

10. ~r.Or.E. àm¡Úmo{JH$s H$m Cn`moJ AmB©.gr.Eg Ho$ {bE {H$`m OmVm h¡ Ohm± {nZm| H$s g§»`m
hmoVr h¡
(H$) 14
(I) 16
(J) 24
(K) ~hþV A{YH$
BGA technology is used for ICs where the number of pins are
(a) 14
(b) 16
(c) 24
(d) Very high

11. H|$Ðr` àg§ñH$aU BH$mB© (gr.nr.`y.) H$m H$m`© h¡
(H$) joÌ H$s VmH$V H$s Om±M H$a|
(I) H$s ~moS>© ñH¡$Z H$a|
(J) ñQ>¢S>~m` Mm{OªJ {Z`§ÌU
(K) Cn`w©º$ g^r
The function of Central Processing Unit (CPU) is to
(a) Check the field strength
(b) Scan the keyboard
(c) Control standby charging
(d) All of the above

12. EH$ Eg.E_.S>r. ñQ>oeZ Ho$ {bE à`moJ {H$`m OmVm h¡
(H$) Q>m§H$m
(I) de-Q>m§H$m
(J) gyIo gmoëS>a H$mo hQ>m X|
(K) Cn`w©º$ g^r
An SMD station is used for
(a) soldering
(b) de-soldering
(c) removing dry solder
(d) All of the above
313 6

{H$Ýht nm±M àíZm| Ho$ CÎma Xr{OE & àË`oH$ àíZ Xmo A§H$ H$m h¡ & 25=10
Attempt any five questions. Each question carries 2 marks.

13. E.E_. _m°S>çyboeZ {gñQ>_ H$s ~¢S>{dS²>W n[a^m{fV H$s{OE &
Define bandwidth of AM modulation system.

14. AmH$me Va§J àgma H$s gr_mE± Š`m h¢ ?
What are the limitations of sky wave propagation ?

15. CnJ«hm| Ho$ H$moB© Xmo AZwà`moJ {b{IE &
Write any two applications of satellites.

16. _mo~mBb \$moZ H$s {d{^Þ nr{‹T>`m| H$mo {b{IE &
Mention the different generations of mobile phones.

17. AmB©.E_.B©.AmB©. Š`m h¡ ?
What is IMEI ?

18. ~r.Or.E. AmB©.gr. Š`m h¡ ?
What is BGA IC ?

19. EH$ _mo~mBb µ\$moZ _| ‘S>çyßboŠg {\$ëQ>a’ H$m Š`m H$m`© hmoVm h¡, g_PmBE &
Explain the function of ‘Duplex Filter’ in a mobile phone.

{H$Ýht nm±M àíZm| Ho$ CÎma Xr{OE & àË`oH$ àíZ VrZ A§H$ H$m h¡ & 35=15
Attempt any five questions. Each question carries 3 marks.

20. _m°Sw>bZ H$s Amdí`H$Vm H$s ì`m»`m H$s{OE &
Explain the need of modulation.

21. g_PmBE {H$ CnJ«hm| Ho$ _mÜ`_ go g§Mma H¡$go hmoVm h¡ &
Explain how communication takes place through satellites.

22. gr.S>r.E_.E. Am¡a Or.Eg.E_. _mo~mBb godmAm§o H$s VwbZm H$s{OE &
Compare CDMA and GSM mobile services.

23. EH$ _mo~mBb µ\$moZ {Og_| dmBag h¡, CgHo$ bjU {b{IE & dmBag go h_ H¡$go ~M gH$Vo
h¢ ?
Write the signs of a virus-infected mobile phone. How can we avoid
viruses ?
313 7 P.T.O.

24. Eg.E_.S>r. AmB©.gr.Eg na H$m_ H$aZo Ho$ ~mao _| {b{IE &
Write about working on SMD ICs.

25. AnZr IwX H$s _mo~mBb _aå_V H$s XþH$mZ ImobZo H$s à{H«$`m {b{IE &
Write the procedure to open your own mobile repair shop.

26. _mo~mBb XþH$mZ _| Amdí`H$ {d{^Þ ñno`a nmQ²>©g Am¡a EgogarµO Š`m h¢ ?
What are the various spare parts and accessories required in a mobile
shop ?
IÊS> ~
SECTION B

{H$Ýht VrZ àíZm| Ho$ CÎma Xr{OE & àË`oH$ àíZ nm±M A§H$ H$m h¡ & 53=15
Attempt any three questions. Each question carries 5 marks.

27. gobwba ao{S>`mo {gñQ>_ Am¡a BgHo$ \$m`Xo Ho$ VÎdm| H$s ì`m»`m H$s{OE &
Explain the elements of cellular radio system and its advantages.

28. Q>obr_oQ´>r Š`m h¡ ? dr.Eg.E.Q>r. VH$ZrH$ Š`m h¡ ?
What is Telemetry ? What is VSAT technology ?

29. Or.nr.Ama.Eg. àUmbr Am¡a CgHo$ AZwà`moJm| Ho$ ~mao _| g_PmBE &
Explain about GPRS system and its applications.

30. H$moS> Am¡a gm°âQ>do`a H$m Cn`moJ H$a _mo~mBb \$moZ Ho$ AZbm°qH$J H$s ì`m»`m H$s{OE &
Explain unlocking of mobile phone using codes and software.

31. _mo~mBb _aå_V H$s XþH$mZ MbmZo Ho$ {bE, CnH$aU, ñno`a nmQ²>g© Am¡a EgogarµO IarXZo Ho$
{bE òmoV {b{IE &
To run a mobile repair shop, write the sources to procure tools, spare
parts and accessories.

313 8