Kenwood YK-88S Marine Radio User Manual


 
TS-440
S
CIRCUIT DESCRIPTIO
N
1
. Encode
r
The TS-440S uses an optical encorder
. Two different cloc
k
signals from the encoder are
90°,
out of phase with eac
h
other
. This phase difference is not adjustable but depend
s
on the precision of the module
. The two clock signals are
converted into clock pulses (250 pulses/rotation x 4) and U/
D
signals indicating the direction of rotation by the 4011 an
d
4030 and fed into the 7800
. Figure 1 5 is a timing chart fo
r
clock pulse and the U/D signal transmitted to the 7800
.
,uPD7800G
Fig
. 14 Encoder circui
t
4I
I
B
6
8
8
8
4
8
3
81
1
C
4
A
4
CI
O
A1
0
C
2
012
84 BI
I
BIO 8
3
BIO 81
1
B4 - B
3
COUNT PULS
E
BIG
I
U/D SIGNA
L
Fig
. 15 Encoder waveform timing chart
19