Kenwood TS-440S Service Manual page 24

TS-440S
1 4 . M ode control s ignals
Tra n smit/receive mode s i g n a l s a re g e n e rated b y IC 1 0 i n the
IF u n it. IC 1 0 is a hyb rid IC conta i n i n g five p a i rs of PNP tran­
s i stors a n d d i o d es.
F i g u re 22 sho ws its equ i v a l e nt c i rc u it. When the mode sig­
n a l s S S B , C W B , RY B , A M B , a n d F M B a re applied to p i n s 6
2 3
18
I
1 5 . Expand function
Control unit (X53- 1 450- 1 1 I
D N o .
6 5
6 6
6 7
7 3
7 8
7 9
24
CIRCUIT D ESCRI PTION
" "
"
'" '"
a:
a:
>-
u_
"'
14
0
I
I
I
I
I
I
10
"
"
'"
<D
<D
u_
Fig. 2 2 Mode control circuit
S h i p p e d
M o d e beep t o n e M o rs e ·
O F F
1 O H z d i s p l a y
M e m o ry p rotect O F F
8 0 0 H z
CW s h ift
TX
w 2 4 N o
TX N o
w 1 8
Table 1 4 Expand function
to 1 0 , the voltages of control p i n s 1 6 a n d 17 cha n g e . D u r­
ing reception, these signals change to SSR, CWR, RYR, A MR,
a n d F MR . D u ri n g transmi s s i on, these s i g n a l s cha nge to SST,
C WT, RYT, A MT, a n d F M T .
;:
>- >­
a:
>-
>-
a:
a: u
"' -
4 "' 12
'"
'"
u
<D
<D
6
<D
u
;:
<D
<D
>­
a:
u
D i o d e c u t
S i n g l e t o n e
O N
O N
400 H z
Y e s
Y e s
1
- - -
GND
8
CONT
1
-2 17
14A
Q l 5 : DTC l l 4ES