3.
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).
113
8.GTVL-A
Cau 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.
114
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.
Chl1ang 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
T
C =331
_0
(m!s)
273
II)
To
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=290
o
K (tuc
Ia
17
n
C).
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
Ruoe 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
chi nghe duqe am
Lhanh
co
tan

so
thap han.
Nguai
gia
nghc ticng thanh kcm
hem
nguoi trc.
0
NgU()'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
D~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
s
T
T
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).
110
2.
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