Advertisement
4-1 . I
N
T
R
OD
U
CTIO
N
42 .
T
h
e t
h
eo
r
y of ope
r
atio
n
is w
r
itten p
r
ima
r
i
l
y at α
f
un
ctional bloc
k
level . Some
d
etaile
d
ci
r
c
u
it t
h
eo
r
y is p
r
ovi
d
e
d
as an ai
d
to t
r
o
u
bles
h
ooti
n
g w
h
en ci
r
cuit com
p
lexity
r
e
qu
i
r
es it . In
a
dd
itio
n
,
br
ief ci
r
c
u
it expla
n
atio
n
s a
r
e give
n
fo
r
two
un
i
qu
e integ
r
ate
d
ci
r
cuit
p
ac
k
ages : t
h
e
Va
r
ia
b
le Time Base Co
un
te
r
a
n
d t
h
e
H
ex
M
ulti
p
lexe
d
Co
un
te
r
s .
4-3 .
FUN
CTIO
N
A
L
D
E
SC
R
IPTIO
N
4-4 . T
h
e 5383Α is α
d
i
r
ect f
r
e
qu
ency co
un
ti
n
g i
n
st
ru
me
n
t w
h
ic
h
comp
u
tes i
npu
t fre
qu
e
n
cy "f"
by cou
n
ti
n
g t
h
e
nu
m
b
e
r
of cycles " η" t
h
at occ
ur
s
dur
i
n
g an i
n
te
rn
ally gene
r
ate
d
time
b
ase
i
n
te
r
val "t" .
T
h
is f
r
e
qu
e
n
cy meas
ur
ement f
un
ctio
n
is
d
escri
b
e
d
sim
p
ly by t
h
e followi
n
g
e
qu
atio
n
:
η =fxt
η = n
um
be
r
of cycles
f = f
r
e
qu
e
n
cy of i
n
p
u
t sig
n
al
t = inte
rn
ally ge
n
e
r
ate
d
time base interval
O
n
ce calculate
d
, " η"
d
ata
mu
st be sam
p
le
d
a
nd
co
rr
ectly t
r
a
n
sfe
r
re
d
to t
h
e
9-
d
igit cou
n
te
r d
is
p
lay .
4-5 . I
NPU
T CI
R
C
U
IT
46 .
(
R
efe
r
to
F
ig
ur
e 4-1 an
d
to sc
h
ematic .) Sig
n
al "f" is a
p
plie
d
to t
h
e i
n
p
u
t ci
r
c
u
its co
n
sisting
of A2S2, A1Q15, a
nd
A1Q14. In
pu
t switc
h
S2
r
o
u
tes t
h
e sig
n
al to eit
h
er t
h
e 1 ΜΩ Χ 1, Χ 10
p
at
h
, o
r
t
h
e t
h
e 50 Ω pat
h
. Q14 an
d
Q15
b
iases t
h
ese sig
n
al pat
h
s, allowi
n
g t
h
e Bala
n
ce
d
I nput Amplifie
r
to
accept eit
h
e
r
t
h
e 50 Ω
o
r
t
h
e 1 ΜΩ sig
n
al (
r
efe
r
to t
h
e sc
h
ematic fo
r d
etaile
d b
iasi
n
g i
n
fo
r
matio
n
a
nd
corresponding signal
p
at
h
selectio
n
) . A2S2 ca
n
also select α 1ΜΩ Χ 10 atte
nu
ato
r
consisti
n
g of
α 1 :10 voltage divi
d
e
r n
etwo
rk
.
T
h
e 50Ω sig
n
al
p
at
h
consists of :
T
h
e 1 ΜΩ Χ 1, Χ10
p
at
h
consists of :
SE
CTIO
N
I
V
TH
EO
R
Y O
F
O
P
E
R
ATIO
N
α .
0 .1 amp fuse Al
F
1 (3 .5
V r
ms maxim
u
m in
p
ut) .
M
o
d
el 5383Α
T
h
eo
r
y of Ope
r
atio
n
b.
Clampi
n
g a
nd
limiti
n
g
d
io
d
es (A1C
R
12 and C
R
13; a
nd
A1C
R
8 t
hru C R
11) whic
h
limit t
h
e
i
n
p
u
t to 1 volt pea
k
-to-pea
k
.
α .
FE
T's A1Q17, Q18, a
nd E
mitte
r
followe
r
A1Q16 .
b .
Α switc
h
able low
p
ass filte
r
consisti
n
g of A1
R
55 a
nd
C44 . 'Boa
rd
-mo
un
te
d
switc
h
A1S2
("F
I
L
T
ER")
switc
h
es t
h
is filte
r
i
n
o
r
o
u
t .
Advertisement
