Beep; Pll And Dds Control Circuit; Tx-Rx Unit Control Signal Circuit - Kenwood TK-80 Service Manual

5-9. Beep

The beep signal is generated using the timer in the micro-
computer. A dot lasts about 40ms, a dash about 120ms. The
oscillation frequency is about 1.4kHz.

5-10. PLL and DDS control circuit

The TK-80 has one PLL and two DDSs. The main micro-
computer outputs frequency data to the PLL and DDSs seri-
ally according to the display frequency.
IC7
I/O port
11
VEN1
10
FEN1
9
FEN2
8
FEN3
34
UCK
35
UDA
IC5
CPU
CONTROL UNIT
CIRCUIT DESCRIPTION
MIC OUT
AFVR
Power control
1 24
VI1 VI8
VO1
VO8 5V
VO2 VO7
VI2 VI7
5V VDD GND
VEN1 RESET
UCK VDA
UDA DO
VI3 VI6
TX GAIN
VO3 VO6
VO4 VO5 CAR level
12 13
VI4 VI5
IC13
D/A converter
CN4 CN14
FEN3 17 FEN3
18
FEN2 FEN2
VEN1 19 VEN1
20
UCK UCK
UDA 21 UDA
FEN1 22 FEN1
TX-RX UNIT
Fig. 14 TX-RX unit control signal

5-11. TX-RX unit control signal circuit

The microcomputer sends the mode signal, IF filter select
signal, power signal, band-pass filter signal, MIC gain, and
CAR level data to the TX-RX unit. It receives meter signals
and standby switch signals from the TX-RX unit, displays data
on the meters, and performs the transmit operation. The
output signal from the microcomputer goes to the serial-to-
parallel converter IC16, IC15 and IC10, D/A converter IC13
(Fig. 14).
IC16
Serial/Parallel
1
Vss Vdd
NC
UDA
DATA SO
UCK
CLK Q11
FEN3
LCK Q10
AM
Q0
Q1
SCB
Q2
Q3
VOXS
Q4
10
IC15
Serial/Parallel
1
Vss Vdd
NC
UDA
DATA SO
UCK
CLK Q11
FEN2
LCK Q10
IF1
Q0
IF2
Q1
IF3
Q2
IF4
Q3
AGS
Q4
10
IC10
Serial/Parallel
9
B8
B7
B6
B5
UDA NC
UCK FEN1
RES
5V
5V GND
16
TK-80
SSB, CW mode signal
AM mode signal
20
5V
OE
MMU2
Q9 MIC mute 2
MMU1
Q8 MIC mute 1
ABK
Q7 AF blanking
VCAS
Q6 VCA singal
PMU
Q5 Power OFF AF blanking
11
VOX signal
20
5V
OE
Q9
AIP
Q8 AIP signal
PL
Q7 Power meter gain signal
RBK
Q6 RF balnking signal
NBS
Q5 NB signal
11
AGS select
IF filter 0.5kHz
IF filter 2.2kHz
IF filter 2.7kHz
IF filter 6.0kHz
RX BPF data
8
B1
B2
B3
B4
EN
1
19