T~i sao trang hau het cac linh kiln diln ILt kh6ng che t~o bang v~1 lilu dan diln ma I~i dung v~llieu ban dan.. So sanh vOi dl;ic tinh dan diln cua chat ban dan linh khiet.. Nguon goe a
Trang 13 each si't d~ng m~ch If) h\lp (IC)
Nhu da noi a tr~n, vi m~ch (Ie) thl!C chat Iii bQ khucch d<;li, toan lx) d,c linh ki¢n duqc hip ghcp tren m¢t tam co cae chan dua fa, mM chan c6 m()t chile nang ricng Theo each phan lO<;li (hla van chuc nang lam vi¢c m~ch 16 h<Jp c6 2 IO<;li la Ie tuycn tinh va Ie so Vai m6i lo~i nay l<;li co ral nhi~u ti'ng d~ng khac nhau Vi the khi ki6m lra va sua chua thay the chung phii am hi6u ky chile nang va chc d() Hun vi¢c ella chung lTOng lung m<;lch C1,l lh~ d ph <in nay chi nh~m cung c<1p m(}t so kicn lhue toi lhi~u va nIt can thiet eho d,c c6ng vi¢c d6 N6i chung kct cau cae m<;lch 16 hqp fin da d<;lng so chan nhicu it khac nhau bao g()m 3, 4, 6, 8, 10, 12, 14, 16,20, 24 v.v, chan phd bien nha't Iii 14 chan (Hlnh 2- 48) TIllT 11! cae chan du<,1c danh dau nhl! sau: neu 11hln m~l sau thi dern cung chi6u kim d6ng ho so chan LII 1 cho den het, ncu nhin m~t trCn (Top Vicw) dcm ngU<.~c chicu kim dong ho
3 \
\
" 7
14
II
II
10
9
8
I-fil1li 2 1-8 '-)'(/ do b6' tri cae cliall ella Ie
SI! b6 tri cae chan tuy then lo~i nlutng n6i chung de vi m~ch ban gio cung
co dc m~ch co ban sau:
~ N6i mat (Mt)
~ Cilp ngu6n
- D<1u vaa
- Dau ra
- Khle dan d(mg ky sinh
- Hoi tiep
•
Trong do m<;lch cap nguon co th~ cap a nhiCu chan, dau vaa - dau ra co th~
co mi)t hay hai M~ch hM tiep co th~ co m9t ho~c hai m~ch va m<;lch khu dao d9ng ky sinh ciJng v~y Vile do Ie phiH co nhieu (t<1u fa (nhi6u chan)
Trang 2Cau hoi va bai tap chU'dng 2
1 Neu dl;ic Unh dan di(ln cua chat ban dan jinh khi~t
2 Phan tfch cac yeu t6 anh hLIC1ng den dl;ic tfnh dan di(ln cua chflt ban dan ( nhi(lt d9, anh sang, cL10ng d9 di(ln truong, tia buc x~ )
3 T~i sao trang hau het cac linh ki(ln di(ln ILt kh6ng che t~o bang v~1 li(lu dan di(ln
ma I~i dung v~llieu ban dan
4 Ph~m lich d~c linh dan di$n cua chat ban dan t~p So sanh vOi dl;ic tinh dan di(ln cua chat ban dan linh khiet
5 Neu mC;;1 s6 (Jng dl,mg cua chat bim dan
6 Neu cau lao, nguyen t~c lam vi(lc, ki hi(lu cua 8iot
7 Phan tich cac dl;ic tfnh cua 8iot
8 So sanh U'U nhL1<;Jc diem cua 8ial giecmani va 8i6t silk
9 Trinh bay cong ngh(l che lao 8ial lo~i tiep diem va tiep m~t
10 Neu nguyen t~c lam vi(lc cua diat Zener, ve d~c tuyen Von - Ampe va cach m.~c
dial vao mach di(ln
11 Neu nguyen lac lam vi(lc cua diot bien dung, ve dl;ic tuyen Von - Ampe va cach mac vao mach di(ln
12 Khi SLr dl:Jng diat can chu y nhCmg diem gl?
13 cau I~o tranzito thu~n, nghich va nguyen uk ho~t dC;;ng
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14 Cach mac Iranzito PNP va f'o!PN CI!C bazo chung, colectd chung, emitor chung Phan tfch kha nang khuech d~i dong, ap , cong suat cua cac lo?i cach ~c
15 Neu eac thOng s6 kithu~t each SLt dl:Jng tranzito, cach kiem tra xac dinh lo~i
tranzito, chan tranzito
16 Cflu ~o ki hi(lu va nguyen tac lam vi(lc cua tranzilo thL1ang JFET
17 Cau t~o, ki hi$u va nguyen t~c ho?t dC;;ng cua tranzito trLIang MOSFET
18 PMn Uch utJ nhLI<;Jc diem cua tranzilo lL1ang cl!C
19 Cau t~o va nguyen lik ho~t dC;;ng cua tranzito 1 liep giap, tranzito 4 ctfC
20 Cau t~o, ki hi(lu, nguyen tac ho~1 d9'l9' ling dl:Jng cua tiristor
21 Cau t~o, sd do tLIdng dLIdng cua Tria!, Diac, di(ln Ird nhi(lt va cac (tng dl:mg
22 Cau t~o, cong ngh(l che I~o, nguyen tac ho~t dC;;ng cua Ie bao Quang dan
23 So sanh 8i6t quang di(ln va triot quang di(ln
24 Trinh bay cau tao cua b9 ngau h<;Jp quang di(ln
25 Neu d.!!\.c diem, cach phan lo~i m~ch 16 h<;Jp IC, cac nguyen tik cd ban de xay dlfng
1 vi mach
26 Phan tich d~c diem cong ngh(l che t~o IC, U'U nhl,fdc diem cua tlIng lo~i
27 Cach SLr dl,lng IC va cach be trf mC;;t s6 chan Iren mC;;t so IC thong dl;lng
Trang 3Chl1ang 3
D1ENTHANH
Di¢n thanh lit ph an hqc nghicll CtTu cau l':l0, nguyen 19 Lim vi~c va cOng (h,mg ella d.c thiel h~ di~n lhanh nht! micn), loa, 6ng nghr.:
I KHAI NltM CHUNG vi!, AM THANH
1 Nguon goe am thanh
Khi La dung tay b~t van day dan, day dim rung l~n va phat fa li6ng Tieng MII1 ngan lIi:l.i, cho de'n khi day di:m het rung thl am thanh cling tal N (l'u La go
If(ing m;;tt Lrt:ing rung len va cfing phat fa licng v.v
NhlI v~y La co th~ kCt lu~n: Am lhanh Iii do v~t th~ rung {h)ng pluil fa Licng
va Hlm IfuyCn di Lrong kh6ng khL Sb dt lai La Ilghc dlIqc am lhanh lil nhb co mang nhi Milng nhi n6i lien v6i h~ than kinh Lrung lIang
Uin song am thanh tit v~t the: rung dl')ng phat fa, duqc Ian truycn Lrong
khOng gian, toi tai La lam rung d(lng mang nhi then dung nh!p di¢u rung d(mg cila v~l Lh0 <fa phat fa lieng Nha do tai La nghc dlIgc am thanh
Am thanh cfing Ian truydn dlf(,1C trong khCmg khl, chat h"mg, chat ran, nhlIng kh6ng truydn Ian trong khoang chan kh6ng,
M()t s6 chcl'L truydn dan am thUllh kcm Cae chat (Hin am kcm thU(Hlg 13 IO<:J.i mdm nhu x6p, h6ng, d<:J., ci'> kh(), Ok chat nay g9i Iil ch.ft hut am, dlf(,1c dung
M 16t tlf(mg cae r<;lp M.l, dc ph(mg 00 am dd hut am, giiim tiCllg vang V~n t6e lruycn Ian cua am thanh phl,l thu(lc vito chat truydn am
rhi d~/; Trong khCmg khlla 340 mis, trong nude IiI 1480 mis, trong ch.rt Sift
I )OOOm/s
Trong kh()ng khl v~n toe lruy~n Ian phl,l thu0c nhi~l d0 va tinh lheo c6ng Ihuc:
Hf
Trang 4To I;) nhi¢t d(> tUy~l d6i eua kh6ng kh1 Nhu v~y nhi¢t d(> dmg eao thl am thanh truycn cang nhanh Nguai ta thuang ehqn C :::: 340 mls la t6e d(> Luong ung vai nhi¢t d(> 'P=290oK (tuc Ia 17nC)
Trong hanh trlnh truyco lan, neu g~p phiii die v~t ehu6ng ngl:li nhu luOng, nui da th' phan 16n nang Iuqog cua am thanh s0 bt philn x!;ltra Il:li, m(>l phein nha tiep ll!c truycn Ian vc phfa truck, con m¢t phan nhb ntra ella nang lUQllg
am thanh bi C9 sal vai chuang ng~i v~t, bittn thanh nhi~t nang lieu tan di
2 £)~c tinh cua am lhanh
Am thanh duge d~c tntng bang cae d~c tfoh nhu sau:
2.1 Tan s6 dao dQng ella am thanh
Tan s6 eua m{?t am don Ia s6Ian dao d<)ng eua khong kill truycn am trong
1 giay dong h6
VD: Khi La gay n(:it mr eua d~1.l1 thl day se rung 330 lan/ gia.y Ta gqi tan s6 eua am mi Ia 330 Hcc,(Hz)
Dan vi clla t<1n 56 Ii:l Hce (viet tit HI Hz)
I Mega Hec (MH/) = 1000 Kilo Hec (KHz) = 1000.000 Hec (Hz)
Tan 56 bicu tht (1<) cao eua am lhanh: Ticng tnim co t<1n s6 thilp, ticng being
co litH s6 cao Tai nguai co th~ nghe duqe cae utn s6 thap toi 16Hz va tan s6 cao lui 20.000Hz
Dili tan s6 tit 16Hz den 20.000Hz gqi Ia dai lan s6 am thanh, gqi 1<lt la am tan Nhll'ng am co tan s6 duai 16Hz gQi Ia hi:l am.Nhll'ng am co tan s6 tren 20.000Hz gQi la sicu am
Dong di9n c6 tan s6trong khoiing 16 dc'n 20.000Hz gQi Ia dong di¢n am tan Oilg voi m6i tiin s6 dao dQng f co ehu ky dao d<)ng T va m<)l buac song (doc 111 lam da) (Hlnh 3 - I)
Chu ky eua dao dQng am thanh la thai gian am do dao dQng dugc 1 Ian Chll ky ky hiell 111 T, c6 dIm vi 111 giay (5), T = 1/ r
0
o
116
Un>: Bien dQ dao d(>ng am thanh T: Chll ky dao dqng Am thanh
HiIlI13-1
Do thi 111m gian etta dao d(mg am thanh
Trang 5Ruoe song eua am thanh ky hi¢u bang A co dan vi la met
) = C.T, C 10 t6c dO truy~n Ian cua am thanh trang kh6ng khl (C=340m!s)
T Iii ehu ky ella am thanh.V~y buoe song ella am thanh ehinh Iii khoiing Ian
lruy~n eua am thanh wang (mg voi mt)t ehu ky dao dOng Ru(re song ella am lhanh luang U'ng teong diii am Lan Ia Lu21,25 m den 0,017 m
Tfcn lhlfe t6' 1 am phat fa tllUOng khOng phii Iii 1 am <.hm, rna Iii m¢t am phue Am phue nay ban gam am dan va 1 s6 am dai co tan s6 gap 2,3,4 hin
am dan
Trong diii am tan, nguai La chia fa: tieng tram tit 16HI den 300Hz, ti6ng vua tit 300Hz den 3000Hz, ticng h6ng (hay tieng thanh) tit 3000Hz den 20.000Hz
Tieng noi eua nguO'i lbu(1ng co tan so lU 80-1200 Hz Cae not nh~c (J hal d() thu 3 co litn s6: dO; 262Hz, fC: 294 Hz, mi: 300HI., pha: 349Hz, la: 440Hz,
sj: 494Hz
2.2 Cong suat am thanh
COng sUift am thanh lit nang luqng am lhanh di qua I di¢n tich Strong thai gian I giay
Cong sua't am thanh P co the tfnh bang eOng lhue:
p = pSv Trong do: pia thanh ap
v Iii v~n toe ella I phan tir khOng khl t~i do
S la di¢n tlch C6ng suat am thanh tfnh then W (mit)
2.3 CI10ng do am thanh
CUOng dl? am thanh Iii eang SU:!l am thanh di qua 1 dan vj di¢n Heh lil I
1= P!S =pv
Ra d~i luqng: A p suat am thanh, eOng sm1l am thanh, eubng dq am lhanh gtlIl
li~n voi nhau: P =IS =pvs Ca 3 d~u hi~u thi dq Ion nho ella am thanh, ihn thanh
co nang luqng cang Ibn th) eang suar, eub"ng dq va ap SU:!l am thanh eang roo
3 51! thl:l cam cua tai ngLtoj doi voj am thanh
Nguai blnh lhuang co th~ nghc duqe am thanh trong dai tan 56 lit 20Hz den 15.000 Hz C6 nguai nghe duqe am thanh co tan s6 eao han co nguai l~i
so
Trang 6NgU()'i la l.:0 Ih0 piuin hi~t <1u9'l.: 130 mul.: thanh ap khac nhau, moi muc ddl nhau 1 ch) Tai ngu(Yi nghe nh~y v(Yi cac tan s6 trong khoang 500Hz den 5000Hz, (''I nhCing u1n s6 nay chi call ngutJn am thanh co thanh ap nh6, nghe cCing kh(mg kern gl a khoang Ian s6 cao hay thap co thanh ap IOn
Tai ngu'{1i c() Lhli phan hil;t dU9c nh[rng am s.ll.: khac nhau
Am Sill.: iii Silc thai rieng cua am thanh, giup ta pha.n hi~t dm,'Ie dc ngu6n
am khac nhau Hai io~i nh~c (.;I,l d.ll1g d<;\o m0t han nh~e nhu nhau nhung nghe kh,k nhau VI c6 am sac kluk nhau Hai am phuc co am cO' han gi6ng nhau ve tan sCi va hien d(), nhung hai am do c6 Hill sCi, hien dl) khac nhau., n0n co am 'i.ll.: khac nhau
Tai nglf(\i c6 khii nang uu li0n nghe r6 d.e licng rna mlnh nghe quen, Chang h<,tn ngut)'i Vi~t Nam nghe ticng Vi~t khi lhuyel minh phim r6 han ticng ngo<;li qu6c Ngu(1i ta co th0 xac dinh dU<;1(.; huang am lhanh truycn 16i nhb hai tai Vi v~y la eo th~ nghe duqc am thanh i~p 1h~
II MICR()
MicrO Iii dl:l11g el,l di~n thanh co lac dl,lng hien d6i na.ng luqng clla de dao
d(~ng am thanh thiinh nang luvng dao d¢ng di~n am loin D~ng cua dao d<)ng
am tan lay ra tll hai dau cua micrO phai gi6ng h~1 d~ng dao d¢ng am thanh dua tai mier()
1 Cac d~c tinh chinh cua micro
J J 1)6 nhay
Dc) nh<;ly cua micro Iii muc di~n ap fa c'1 hai dau ra cua micro (do ('1100Hz) khi mien) dU(,1l.: da.'u dung tai va thanh lip 0 truDe micro lil 1 micr() har ( har ), Don vt trnh de) nh~y la milivOn tr0n moi micrO har (m V /~har), D() nh';ly eua micro con c6 lh0 trnh ia muc e6ng sua'! ra tren tiii chuan khi thanh ap i'riruac micro Iii I~har D(l nh<,ty nay tfnh theo mW,
D<) nh<;ty eua mien) cCing thuOng Hnh theo <texi Ben (dB) Micr() nao d) £1(>
nh<,ty t(nh theo dB cang 1<'111 thl <1(> nh':lY cang lOn, ChAng h<.i-n micro c6 d() nh<;ly -55dR khoc 11(111 mien) eo (1<) nhl!y -70dB
1.2 D<)c tuyen tan so
D~e tuycn tan so eua mier() hi0u tht si! hien t16i mue di~11 ra eua micrO khi tan sCi thay d6i No ph an anh d<) trung tlWe cua mierC) Dai Ian s6 eang [()ng va dc) kh6ng d6ng deu eua n6 cang 11hZ, thl chat luqng eua micrO cang ca~
IIX
Trang 7D~e lUycn tan s6 eua mien) call phu hgp vai may tilng am va vdi yeu du Sll dl:.li1g D~e tuycn litn so con kcm lhco mue khOng d6ng d~u eua n6 tinh 1hco dB
J.J Tra khang danh dinh
C62 IO<;li trb khang:
- Micro lr(1 khang lhap e6 tri1 khang 2000m 250 Om, 60 (,m nhu ph:ln Ian d.e micrfJ eu(m day eua Lien XO
Micn) e6 tft)" khang can: C6 1ra khang hang ehl,lc kilO Om trb len nhu cac min() tinh lh~, hay m(Jl s6 micro cuon day ella Trung Qu6e
M9t s6 micrO e6 d 2 mU'c lrb khang (eao va thlip)
1.4 Bup hu·ong eua micro
Ri~u th~ sl! hien d6i vc d¢ nhl;ly eua micrO lUy thco huang cua ngu6n am thanh dqi vao micrO
Hlnh 3-2 RiC:u th~ cae ki6u bup huang eua micrO
S I
s
I
TI
I
M
I Jillh 3-2: Cue d(,mg blip huang ell£} micro
Khi bict bup l1U6ng micro lhl bict ch<.H1lo<;li micro dung b eha tbfch hqp va biet each b6 lri micro lhu 16t va tninh duqc tieng ru (Larscn)
Trang 82 Cac IOClii micro
- Micro di~n d()ng ki6u cu()n day Day la ki~u micro thong d~ng nhat
- Micro tinh th0
- Micro tI} di~n
- Micro than
Tren hinh 3-3 minh ho~ lo~i micro di~n d()ng
I MiJIIg micro
2 M4IlIg 1i1t~1/
3 CI/(J/1 day
4 Kite Sal c6 lit rndl1/g 1/I(111h rlll(img g()i hI khe II,
5 NUIIl c/tam !lillll III/(ill
6, 1'1"1,1 Sal IIUI/
7 (/lIg IIwuf hi
8 /)41 II/if dill
Ifilllt 3-3: CUll Ir,lO micro di¢n d(JlIg
3 sli dl;Jng, bao quan micro
3.1 Slr dl:mg lo~i micro thich hgp
Neu la may tang am hay ghi am co tri'1 khang va~ nho thi dung micrC) cO tri')' khang lhap, neu la may lang am co tn'" khang van IOn thi dung micro c6 lra khang eao
Cac did truyen lhanh Cl)' S<1 chi n~n dung micr6 di~n lh)ng ki0u CU(Jll day Cling lIu dam hao chat luqng, I~i M str dl,lng, it hu hbng Neu dung trang am cac CUl)C h9P, hqc t~p, mft tinh, ca nh<,lc ph6 thong cling chi can dung lo~i
mien) di~n d()ng chat 1U(1ng lhuimg
Trong tru{J'ng hqp phai thu de huDi bi~u di~n nh<,lc giao huang cac budi ca nh<,lc d~c bi~t thi mdi dung den d.c micrC) tt! di~n ho~c micro diGn c1qng ki~u
cuqn day co d~c luyen tan s6 r(mg Khi dung d.c IO<,li micro nay pha.i he! SIfC
nht; nhang, lninh va ch<,lm c6 th~ lam hong micrO
120