Kenwood TS-830S Service Manual page 4

Frequency organization of the PLL circult
IS
shown In Figure
I, the c i r c u ~ t diagram in Figure 2, and frequency organlzatlon
in other circuits is summarized in Table 4 . Please refer to
Figure 1 when reading the following description on PLL clr-
cuit operation MIX (3), a double balanced mixer, mlxes the
CAR output wlth the VFO output. MIX ( 2 ) w h ~ c h operates in
18 MHz bands and above, mlxes e ~ t h e r 1 0 NIHz, In the 1 4
and 1 8 MHz bands, or 2 0 MHz, In the 2 1 , 2 4 5, and 2 8 I W Hz
bands, wlth the output of MIX ( 3 ) to generate the
appropriate
frequency needed for each band, as shown In Table 4
This
I S
mrxed wlth the VCO output for each band by MIX ( 1 )
to a frequency given In Table 4 , whlch
I S
then routed through
LPF ( 1
),
amplified, and wave-shaped to a dlgltal signal
A
programmable divider divides thls slgnal into a 5 0 0 kHz out-
put. This programmable divlder
IS
preset, as shown In Table
4, by the BCD signal whlch
IS
counter-generated from Infor-
mation coming from the band swltch The phase comparator
used
I S
a Motorola M C 4 0 4 4 P The loop filter
IS
made of
completely external components to m ~ n ~ m i z e spurtous radia-
tlon
Six VCOs cover all bands. If the PLL unlocks for any
reason, it will be detected from the phase comparator out-
put. T h ~ s will turn off the VCO output to prevent spurious
radiation and, at the same time, the digital d~splay will be
blanked to Inform the operator of unlock status.
Table 6. Frequency chart
CENTER 8.83MHt M 1%
455KHz
.
FROM RF AMP
CERAMIC
-
A F
t
FILTER
IF AMP
---m~
DET
I \
r
-.-------------
r------
1
1
- . I
1
(VBT OSC)
,
MlX(1,
1
I
-
I 01-6 0 1 1
B P F I
lOMHz
I
I
-
1.0-
I
I
4.5MHz (14.18)
or 20MHz
I
4 5 5
P D
(2i924.5,28)
MIX(2)
I
?
L P F l
I
,,
K"z MIX
USB 8
83I5MHz
1
Q17
-
0 3 6
12
A
L S B 8 8285MHz
I '
'i-
I
C W ( R ) 8 8315MHz
C W ( T ) 8 8307MHz
MIX(3)
I
CAR OSC
4fi
F(8.8315)
i / N
4
B P F 2
. =
I
"'"
041.42
I
I
5 0 0 ~ ~ ~ STD OSC lOMHt
84 4
I
DIVIDER
USE 456 5kHz
L-----------------
LSB 4535kHz
CW(R) 456 5kHz
CW(T) 455 7kHz
5.5-6.OMHz
CW(T)
VFO frequency goes 800 Hz
VFO
up at CW transrnlt
Y
8.83MHz MIX 4 5 5 ~ ~ ~ '
y
BPF
4
X'TAL CERAMIC
MIC AMP
MIX(TX1
o--
IF A W
BM
*
FILTER
/
Fig. 1 TS-830 Frequency configuration
M I X
I
1)
Output
( M H z )
4 , 0
2 . 0
1 . 5
4 . 5
2 . 5
I
Division
ratio
1/8
1/4
I
1/3
1/9
1/3
1/5
BAND
1 . 5
3 ' 5
l o
l 4
l 8
DCBA
1 0 0 0
1 1 0 0
1 1 0 1
0 1 1 1
1 1 0 1
1 0 1 1
2 9 . 5
RX. Tx
frequ-
ency
( M H z )
1 . 5
- 2 . 0
3 . 5
- 4 . 0
7 . 0
I
- 7 . 5
1 0 . 0
- 1 0 . 5
1 4 . 0
- 1 4 . 5
1 8 . 0
- 1 8 . 5
2 1 . 0
2 9 . 5
-
3 0 . 0
VCO
( M H Z )
1 0 . 3 3
- 1 0 . 8 8
1 2 . 3 3
- 1 2 . 8 3
1 5 . 8 3
- 1 6 . 3 3
1 8 . 8 3
- 1 9 . 3 3
2 2 . 8 3
- 2 3 . 3 3
2 6 . 8 3
- 2 7 . 3 3
2 9 . 8 3
M I X
(
I
I
input
( M H z )
1 4 . 3 3
- 1 4 . 8 3
14.33
- 1 4 . 8 3
1 4 . 3 3
- 1 4 . 8 3
1 4 . 3 3
- 1 4 . 8 3
24.33
- 2 4 . 8 3
24.33
- 2 4 . 8 3
34.33
3 8 . 3 3
- 3 8 . 8 3
I
4 . 0 1/8 1 0 0 0