TS-5700
6
CIRC U IT D ESCRI PTI O N
•
Loca l Sig n a l s
(l01
a n d CAR)
1 ) L01
Table 2 lists the DDS2 frequency configuration.
DDS2 varies from 540 to 1 040kHz. When the display
frequency is 490 or 990kHz (for example, 1 3.99MHz,
1 4.49MHz), 540kHz is output. When the display fre
quency increases, the DDS2 frequency increases by
the amount of change. When the frequency reaches
1 440kHz, the frequency is switched to 540kHz. When
the frequency increases to 500kHz (and 1 MHz), the
frequency returns to 540kHz. (Figure 4)
By changing the 500kHz band in synchronization
with the display frequency, the 500kHz comparison
PLL circuit is locked and L01 is generated.
As shown in Table 2, DDS2 ( L01 ) frequency con
figuration, the frequency is shifted according to the
offset (IF filter setting), RIT, XIT, production mode car
rier correction value, and IF shift.
Component
L S B
U S S
cw
RX
TX
RX
TX
RX
TX
BAS E
Offset
WIDE (2 4k)
- 1 . 5k
-1 . 5k + 1 . 5k
+ 1 . 5 k
+ 0 . 7 k
+ 0 . 7 k
N A R 11 800)
- 1 . 5k -1 . 5k
+ 1 . 5 k
+ 1 . 5 k
+ 0 . 4 k
+ 0 . 4 k
NAR
(500/270)
- 1 . 5k -1 . 5k
+ 1 . 5 k
+ 1 . 5 k
0
0
CW pitch
-
-
-
-
-
-
FSK tone (H)
-
-
-
-
-
-
FSK tone ( L)
-
-
-
-
-
-
FSK s h ift ( M )
-
-
-
-
-
-
FSK s h ift (S)
-
-
-
-
-
-
R I T
+ ( R I T)
-
+IR I T)
-
+ ( R I T)
-
XIT
-
+ (XIT)
-
+ (XIT)
-
+ (XIT)
CAR s u p p ression
-(CAR LI -(CAR LI +(CAR U)
+(CAR Ui
-
-
I F s h ift
-( I F S)
-
+ ( I F S)
-
+ ( I F S)
-
2) CAR
Table 3 lists the DDS1 frequency configuration.
The 8. 83MHz CAR frequency is generated by the
chopper circuit. The DDS1 output frequency is
1 .1 7M Hz. The CAR frequency is shifted according to
the offset (IF filter setting) correction, carrier correc
tion value, IF shift, CW pitch, and FSK tone.
1040
'N
I
2
I
:
,.,
--
_____
!
_____
L
13.99
14.49
14.99
Display frequency
(MHz)
Fig. 4
D D S 2 11 Hz)
CW- R
FSK
FSK-R
A M
F M
R X
TX
RX
TX
RX
TX
RX
TX
RX
TX
540 k H z - 1 040 k H z
-0 . 7 k
-0 . 7 k -85
-85
+85
+ 8 5
0
0
0
0
-0.4k
-0.4k -85
-85
+85
+85
0
0
0
0
0
0
-85
-85
+85
+85
0
0
0
0
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
+ ( R I T)
-
+ ( R I T)
-
+ ( R I T)
-
+ ( R I T)
-
+IR I T)
-
-
+ (XIT)
-
+ (XIT)
-
+ (XIT)
-
+ (XIT)
-
+ (XIT)
-
-
-
-
-
-
-
-
-
-
-( I F S)
-
-( I F S)
-
+ ( I F S)
-
-
-
-
-
Table 2 DDS2
(L01 )
frequency confi g u ration