Final Unit Control Signal; At Unit Control Signal; Selective Call Unit Control Signal - Kenwood TK-80 Service Manual

TK-80

5-12. Final unit control signal

The transmission LPF section signal and KAT-2 control sig-
nal to the final unit are output as serial data (Fig. 15).

5-13. AT unit control signal

Concerning the preset AT, based on the KAT-2 installation
signal (ATI), variable condenser position data (POD1, POD2)
and preset position data, the CPU controls the variable con-
denser drive motor rotation direction and rotation speed, us-
ing feedback control to ensure it stops at preset positions.
The tap signal from the tuning circuit is synthesized from the
transmit LPF selection signal from the final unit.
The KAT-2 does not tune below 2.0MHz, forcibly entering
the AT-through mode (Fig. 16).
5V 14V
IC7
I/O port
40
APRE
41
ATA
39
PR11
38
PR12
37
PR21
36
PR22
9
SPED
57
ATI
69
Vref
70
AVss
72
POD1
73
POD2
IC5
CPU
Fig. 16 KAT-2 control circuit
20
CIRCUIT DESCRIPTION
IC7
I/O port
7
FEN4
CN3
FEN4
34 UCK
UCK
UDA
35
UDA
IC5
CPU
CONTROL UNIT
Fig. 15 Final unit control signal
CN6
DGND
1
DGND
2
5A
3
14S
4
ATI
5
SPED
6
APRE
7
ATA
8
PR11
9
PR12
10
PR21
11
PR22
12
ATG
13
VREF
14
POD2
15
POD1
16
The MAT-100 control signal is bi-directional and conducts
tuning while handshaking with the MAT-100 (Fig. 17).

5-14. Selective call unit control signal

Based on the KPE-1 installation signal, DTMF decode
data, FSK decode data and other data, the CPU transmits call
codes, turns AF muting on and off, etc.
Band data decoder
28AT 11
Q5
24AT
Q6
21AT
Q7
LPF3
Q8
LPF4
Q9
Q10
Q11
SO
OE
CN3
5V Vdd
20
3
4
5
FINAL UNIT
IC7
I/O port
22
TTO
21
TSO
IC5
5V
CPU
56
TTI
55
TSI
Fig. 17 MAT-100 conrol circuit
LPF4 select
LPF3 select
21AT select
24AT select
28AT select
IC4
10
LPF1
Q4 LPF1 select
LPF2
Q3 LPF2 select
LPF5
Q2 LPF5 select
LPF6
LPF6 select
Q1
18AT
Q0 18AT select
FEN4
LCK
UCK
CLK
UDA
DATA
NC
Vss
1
CN3
Q5
TT
TS
Q3
Q6
Q4
CONTROL UNIT
1
2