Technics ST-9038 User Manual

i
PART
II
PLL
SYNTHESIZER
û
1-5-3
Frequency
division
in variable
code
presetting
After
the 586
frequency
division
by
the
fixed
codes,
"
l"
is
put
out
at
the OUT
of 861C
Bl4LS76
is
inverted
by
this
pulse.
Then
O =
"1"
and
O
-
'tott
*
Frequency
divis¡on
in variable
code
presetting
f¡n
o
9
-1
O¡
ol
9ry
Contents
of
74L5192
Borrow
out of
74L5192
Contents
of
tPD861
C
40
Output
of
I
PÐ861
C
A
74L574
A
B
74L574
0
B
74L574 Q.
(
Load
signal)
Tima chart
Now suppose
that the received
frequgncy is
90.1
MHz, then the
content of the
scanning
counter
¡s
ilQOO] t0101Ol
. Therefore,
from the tables of true
values for
OR and
AND,
codes
[1000]-
tl
l
and
[010101]
142)
are respect¡vely
added to 74LS192
and 861C.
The subsequent
operations
are basically
the
same
as
for the
frequency division
by
fixed codes.
The only
difference
is that
the
number
preset
into 74LS192
with
the
load signal
given
is
"1"
instead
of
"5"
in fixed
code.
The counting operations are I
-
2*1"*O*e+Q+9*8
"""""" lf
includes two
extra
pulses
as shown
by the circled
numbers.
That
is, the
number
of
frequency
divisions
by the
varíable
codes
in
90.1
MHz
is 422 oblained
by
adding 2 and
10
x 42
=
420
that
is
the
number of
frequency
divisions by 74LS192
and 861C.
Therefoie, the
frequency
dividing
ratio
in 90.1
MHz is:
586
+
422
=
1008
--*+1
i
1008
9-2
I
1
t
,o
41
$
rÇ
7

Technics ST-9038 Specifications

General

Brand	Technics
Model	ST-9038
Category	Tuner
Language	English