TS-440S
CIRCUIT DESCRIPTION
3 0 K ......
30MHz
45.05MHz
8.83MHz
455 KHz
l= 1800 {=450)
J=7244 C=-18111
( l'
F M
CAR
AMR,FMR
AMT
I
FMT
LSB,FSK
455 KHz
456. 5 .,
453.5
�
: 9 1 MHz
: 91.3 MHz
; 90. 7 MHz
I
AM, FM
: K= 18200
:use.cw
:K=JS260
ILSB,FSK
:K=l8140
I
_
_J
MKR
(•13720-2011•)
I I
RIT,XIT
IFCHIFT
Fig . 2 PLL frequency configuration
As shown in fig ure
2,
all received freq uencies excl u ding the
local oscillator frequency fLO are generated in the PLL circuit .
The frequencies generated in these loops are expressed as
fol lows:
VC05:
VC04:
VC03:
VC02:
VC0 1:
1
fvco5
4
·fsro
J
fvco5
1
·fsro
fvco4
4
----
fvco4
K
fvco3
L
fvco2 +
fvco2
1800
1
4
·fsro
1800
fvco3
fvco3
+ fvco4
50
20
M
M
·
f
1800
STD
J
41
fsro
..
.
. .
.
2
K
7200
fsro
...
3
L
7200
fsro
. .
..
4
1
- ·fsro
4
450
fvco3
50
fvco4
20
.
.
5
fvco1
-
f
L
o
- fsro
+
fvco2
1
-
·fsro
10
4
N
18
fvco1
N
+ho +
fsro
fvco2
6
=
-
fsro
.
. .
72
10
Based on these formulas, the frequencies
fvco.
fHET. and fcAR
a re expressed as follows:
M
L
1800
+
3600000
K
+
1440000
+
1
}
·
fsro
+
fLo . . . . . . 7
fvco5
J
41
fsro
. . . . . .
.
.
.
. .
..
. . . . . . . .
.
. . . . . . . . . . . .
8
fvco4
K
fcAR
200
1440000
fsro
· · · · · · · · · · · · · · · · · · · · · · · · ·
9
Formu la
may now be rew ritten as fol lows:
L
(
N
M
fiN
�
- 1 80000
+
3600000
±i
+
1
}
·
fsro
............. 10
N ote that fLO is not included in formu l a
10
. That is, a
received freq uency is dete rmined by the reference frequen
cy
fsro
a n d frequency division d ata I to N. F u rther ana lysis
of formu la
10
shows the following:
i) Basical ly, frequency division data I to N contain no er
ror because they a re controlled by the microproces
sor according to the operating frequency.
ii) The accuracy of the operating freq uency is equal to
that of the reference frequency, because all frequen
cies other than
fsro
in formula
1 0
are determined
by the microprocessor .
iii) T h e operating frequency d o e s n o t c h a n g e even i f k or
fLO changes .
When f1N
=
14
MHz (USB mode) in formu la
10
, f1N and
fsro
have the fol lowing relationship:
5