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3 - 10
3-6-3 MAIN-A UNIT
3-6-4 CTRL-A AND PLL UNITS
3-7 LOGIC CIRCUITS
3-7-2 SUB-CPU PORT ALLOCATIONS
(DISPLAY BOARD; IC401)
LINE
R8V
T8V
DESCRIPTION
Receive 8 V converted from the 14 V line and
regulated by the R8V regulator circuit (Q601,
Q602, D601).
Transmit 8 V converted from the 14 V line and
regulated by the T8V regulator circuit (Q611,
Q612, D611).
LINE
5V
5V
DESCRIPTION
Common 5 V for the antenna tuner CPU
(CTRL-A unit; IC5), EEPROM (CTRL-A unit;
IC6) and etc. converted from the 14 V line and
regulated by the +5 regulator circuit (CTRL-A
unit; IC13).
Common 5 V for each PLL-A and PLL-B circuits
regulated from the 8 V line and regulated by
the +5 regulator circuit (PLL unit; IC382: PLL-A,
IC682: PLL-B).
7, 8
9
12, 83
56, 57
64–66
67–75
77, 79
81
82, 84
85, 88
86
87
92
93
94
95
96
97
98
99
100
Input and output ports for the system
clock oscillator (X401; 9.8304 MHz).
Input port for the reset signal.
Input port for the [DIAL]; pulse-type
signals are applied.
Input ports for the [ELEC-KEY] jack.
Output ports for the S/RF meter back-
light and function switch activation
indicator brightness control signal.
Control signal output ports for the
activation indicator of function switch-
es.
High : When the function is activated.
Input port for the [TWIN PBT (inner)]
control (PBT board, S1/inner).
Outputs the S/RF meter (ME1) drive
signal.
Input ports for the [RIT/
∆
TX] control;
pulse-type signals are applied.
Input port for the [TWIN PBT(outer)]
control (PBT board, S1/outer).
Input port for data signal from the
main-CPU (MAIN-A unit; IC3501).
Outputs data signal for the main-CPU
(MAIN-A unit; IC3501).
A/D input port for the [BAL] control
(R702/ inner).
A/D input port for the [NR] control
(R702/ outer).
A/D input port for the [MIC GAIN]
control (R712).
Input port for the [RF POWER] con-
trol (R714).
Input port for the [COMP] control
(R716).
Input port for the [KEY SPEED] con-
trol (R718).
Input port for the [BK-IN DELAY] con-
trol (R720).
Input port for the [NOTCH] control
(PBT board, R1/inner).
Input port for the [CW PITCH] control
(PBT board, R1/outer).
OSC1,
OSC2
DRES
MSB,
MSA
DOTK,
DSHK
MDM0–
MDM2
TNRD, MOND
NBD, NRD
LOCD, TXD
RXD, PBTD
NOTD
PB1B,
PB1A
METV
RSA,
RSB
PB2A,
PB2B
LMFD
LFMD
BALL
NRL
MIGL
PWRL
CMPL
KYSL
DELL
NOTL
PITL
Pin
Port
Description
number
name
Backlight level
Port
1
2
3
4
5
6
7
MDM0
MDM1
MDM2
High
High High
High High
Low
Low Low
Low High
High High High High
Low High
High
Low
Low Low Low
3-7-1 BAND SELECTION DATA
(RF-B, CTRL-A, PLL UNITS)
Frequency
[MHz]
IC401–IC403
(RF-B )
IC11
(CTRL-A)
IC101
(PLL)
IC401
(PLL)
0.03–1.5999999
B0
L1S
VA1S
VB1S
1.6–1.999999
B1
2.0–2.999999
B2
L2S
3.0–3.999999
B3
4.0–4.999999
B4
5.0–5.999999
L3S
6.0–6.999999
B5W
7.0–7.299999
B5
7.3–7.999999
B5W
8.0–10.999999
B6
L4S
VA2S
VB2S
11.0–11.999999
B7W
12.0–13.999999
L5S
14.0–14.499999
B7
14.5–14.999999
B7W
15.0–19.999999
B8W
L6S
20.0–20.999999
VA3S
VB3S
21.0–21.499999
B8
21.5–21.999999
B8W
22.0–29.999999
B9
L7S
30.0–44.999999
B10W
L8S
45.0–49.999999
VA4S
VB4S
50.0–54.000000
B10
54.0–60.000000
B10W