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Mt s cu hi n tpMn k thut truyn hnh

Cu 1: Tiu chun truyn hnh trng en CCIR qui nh: s dng qut trong mi hnh l625, s hnh trong 1s l 25 v cch qut cc dng xen k. Hy gii thch:- Cs ca vic chn 625 dng /1 hnh v 25 hnh/1s- Trnh by phng php qut xen k v u im ca n so vi qut lin tc- V c tuyn bin tn ca phn cao tn tn hiu hnh.

Cu 2: Trong s khi ca tivi trng en hy nu cc c im v yu cu cbn cakhi khuch i trung tn hnh (Video IF AMP). C hnh v minh ho.

Cu 3: Mch tch sng hnh v khuch i hnhV s khi v c im ca mch tch sng hnh v khuch i hnh

Cu 4: Mch ng b- V hnh mt xungng b , xung xo mnh (dc) theo tiu chun FCC trnh by vs phn chia xung ny thnh cc xung nh hn.- V sao xung ng b ngang khng tc ng c vo mch V.osc (dao ng dc) cth lm sai dao ng dc.

Cu 5: Mch t ng iu chnh khuch i :- V s khi minh ho cho nguyn tc hot ng ca mt mch AGC theo nguyntc AGC kho .- Nu u im ca AGC kho so vi cc loi AGC khc.

Cu 6: Mch qut ngang- V s khi ca mch qut ngang- Mch qut ngang cung cp in p mt chiu cho cc b phn no v cung cp tn hiucho cc phn no trong my thu hnh. - V s tng ng ca mch khuch i cng sut ngang v trnh by nguyn l hotng ca mch (km theo hnh v) hiu c cch to ra dng xung Parabol trong cundy Flyback.

Cu 7: Cs vt l ca truyn hnh mu- nh ngha mu sc v nu cc c tnh ca mu sc: chi, bo ho v sc thi

mu.

- Nu ngha ca thuyt 3 mu- V sao thuyt mu chn 3 mu R, G, B lm 3 mu cbn ch khng phi l 4 mu hay

5 mu cbn?- Sng mang mu (sng ti mu) c dng l g?- Nu iu kin chn sng mang ph (sng mang mu) fsc -

Nu th nghim kim chng l thuyt 3 mu v gii thch s trn mu.

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- Trnh by nhng u khuyt im chnh ca 3 loi n hnh mu: delta, trinitron v inline. (ngn gn, khng cn trnh by chi tit v cu to ca tng loi).

Cu 8: Thit lp h truyn hnh mu- V sao ngi ta dng sng mang ph fsc iu ch mu trong qu trnh to tn hiumutng hp.- Nu iu kin chn sng mang ph fsc ca h NTSC

Cu 9: H mu PAL- V s mch m ho tn hiu PAL to tn hiu video tng hp i pht h PAL v

v dng sng ca tn hiu ny.- Nu tc dng ca tn hiu Burst.- Ti sao ngi ta truyn tn hiu Burst vi di 8 -12 chu k sng sine tn s bng sng

ti ph fsc ch khng truyn c sng fsc n my thu.- Trnh by mch x l trit sai pha 3D ca my thu h PAL v qu trnh t sa sai pha

ca n.

Cu 10: H mu NTSC- So snh nhng u khuyt im ca h NTSC v h PAL.- So snh nhng im ging nhau v khc nhau gia 2 hai h NTSC v PAL- V s khi to tn hiu VIDEO tng hp i pht NTSC v v dng sng ca tn

hiu ny.- Tn hiu Burst trong h NTSC dng lm g?- Nu phn i pht ngi ta dng phng php iu ch cn bng trit sng mang

SAM iu ch mu th my thu ngi ta dng mch g tch sng mu.-

Trnh by cc biu thc ton hc biu din qu trnh gii m mu

Cu 11 :- So snh nhng u khuyt im ca truyn hnh tng t v truyn hnh s.- Trnh by nguyn tc gim tc bt trong k thut truyn hnh s.- Nu 2 phng php bin i tn hiu video t dng tng t sang dng s trong truyn

hnh s . u khuyt im ca chng. Tnh bng thng ti thiu ca 2 phng php ny.- Trnh by s khi ca h thng truyn hnh s v s khi ca b nh nh s.- V s khi ca 2 loi b nh: lm vic theo nguyn l ghi dch v nguyn l ghi c

ty . Nu phm vi ng dng ca chng. -

Nu c im tng qut ca 3 phng thc truyn dn theo H DVB- Cc tiu chun truyn hnh s phn gii caoCu 12 :- Trnh by s khi v nguyn l hot ng ca cc khi trong my thu hnh mu a h

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