Technics ST-9038 User Manual

t
PART
IT
PLL SYNTHESIZER
o
1-4 Prescaler
o-{
The local
oscillator
frequency
for
rhe
FM
broadcasring
band of
97.6
(88.1)
-
107.g
MHz
is
gB.3
(98.8)
-
118.6
MHz
or 10.7
MHz
higher than
the
broadcast
band. To
divide
this frequency
with a
variable
divider
is
difficult
for
an ordinary
TTL
lC
whose
dividing
capacity
is
only
1O
-
20 MHz.
Therefore,
a high
speed
scaling
circuit or
a
prescaler
is
used in
this equipment.
That is,
Vco is
divided
by
the
extra-high
speed
fixed
divider
to lower
the frequency
beforehand.
To
achieve
this
we
use extra-high
ECL,
SVlMC10131P
and
SVlSN74LS76
lC'stodividerhefrequencyattheratio
of 1/8.
A.
10131P B. 10131P
A. 74LS76
f in.
98.3
(98.8)
118.6
MHz
f in
(VCO)
(4.10131P
Ce1)
A
1013rP 01
(8.10131P
Ce2)
1/a
B 10131P
02
{A.
74LS76 CK)
12.2A75
(12.351
14.825 Ml.lz
A. 74LS76
q
Time chart
¡
ü
o
Both
10131P
and 74L576 are equipped
with
two
stages of FIF
cÍrcuit
(flip-flop
circuit).
And
the
output is inverted
when the clock
(CK)
input
ir
"1",
that
is,
when it changes from
"1
"
ro
"o".
ln the
time
chart, when
fin is
"
1",
the 01
output
of A10131p
changes from
"o"
to
"1".
with
the next
fin
"]-',
it changes
from
"1"
ro
"0".
Thus,
each stage of F/F.circuit
divides the
frequency
at the
ratio of 1/2,that
is, 1/B
¡n
3 stages.
2
o

Technics ST-9038 Specifications

General

Brand	Technics
Model	ST-9038
Category	Tuner
Language	English