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• BFO frequency
IF shift: Center, RTTY: Normal polarity
3-4 LOGIC CIRCUITS
3-4-1 BAND SELECTION DATA
(MAIN BOARD AND PLL UNIT)
To select the correct RF low-pass filter, high-pass filter and
VCOs on the PLL unit, the CPU outputs the following band
selection data from the I/O expander (MAIN board; IC2231,
IC2232), the D/A converter (MAIN board; IC2201) or DDS IC
(PLL unit; IC101) depending on the display frequency.
The D/A convertor output from IC2201 (pin 18) is doubled at
IC891d to obtain the band voltage for external equipment.
• Band selection data
3-4-2 SUB CPU PORT ALLOCATIONS
(DISPLAY board; IC1)
3 - 8
USB
LSB
CW
CW-R
RTTY
AM
FM
FM nar.
WFM
9.0130
9.0100
9.0106
(–CW pitch frequency)
9.0106
(+CW pitch frequency)
9.008375 (2125 Hz tone)
9.008885 (1615 Hz tone)
No output
9.4665 (3rd LO)
9.4650 (3rd LO)
No output
9.0130
9.0100
9.0106
(–CW pitch frequency)
9.0106
(+CW pitch freqency)
9.0105 (MARK)
9.0100
9.0115 (PLL ref.)
9.0100 (PLL ref.)
No output
Mode
RX BFO/3rd LO
TX BFO/FM PLL ref.
frequency [MHz]
frequency [MHz]
0.03– 1.999999
2.0–
3.999999
4.0–
7.999999
8.0– 10.999999
11.0– 14.999999
15.0– 21.999999
22.0– 29.999999
30.0– 39.999999
40.0– 59.999999
60.0–128.999999
129.0–143.999999
144.0–148.000000
148.000001–
199.999999
400.000000–
470.000000
IC2231,
IC2201
IC101
IC2232
(MAIN)
(PLL)
Frequency
(MAIN)
[MHz]
HPF
LPF
1/2 band
VCO
LPF
BPF
LPF
voltage
BPF
L1
L2
L3
L4
L5
L6
B7W
B7
B8
B9
L1
L2
L3
L4
L5
L6
L7
L8
B9
3.70 V
3.19 V
2.68 V
0 V
2.18 V
1.69 V
1.19 V
0.96 V
VCO1
VCO2
VCO1
VCO2
VCO3
LOF1
LOF2
LOF3
LOF4
LOF5
LOF4
LOF6
1
18
19, 20
80
81
96
97
98
99
Input port for the [SHIFT] control.
Outputs a PTT signal.
Low : While transmitting.
Outputs displaly backlight control sig-
nal.
Input port for the [PHONES] jack con-
nection detection.
High : When the headphone or
external speaker is connected
to the [PHONES] jack.
Input port for the [RIT] switch.
Input port for the [PTT] switch on the
microphone.
Input port for the microphone up/down
signal.
Input port for the [AF] control.
Input port for the [RF/SQL] control.
SFTL
PTTS
BU1S,
BU2S
PHNK
RSK
PTTL
FUDL
AFGL
SQLL
Pin
Port
Description
number
name
3-4-3 I/O EXPANDER PORT ALLOCATIONS
(MAIN board; IC2221)
4
5
6
7
11, 12
13
14
Outputs select signal for the Tx AF
selector switch (IC1141).
Hign : When AM and SSB modes
are selected.
Outputs AM mode select signal.
High : When AM mode is selected.
Outputs FM and FM-N modes select
signal.
High : When FM and FM-N modes
are selected.
Outputs WFM mode select signal.
High : When WFM mode is selected.
Output select signals for the Rx AF
selector switch (IC861).
Outputs non-FM mode select signal.
High : When SSB/CW/RTTY/AM
modes are selected.
Outputs an audio mute signal for the
analog switch (IC971).
High :
While transmitting in
CW/RTTY modes.
MODS
AMS
FMS
WFMS
AFS1,
AFS2
UNFM
MINH
Pin
Port
Description
number
name
PORT
MODE
WFM
FM
AM
SSB/CW/RTTY
AFS1
High
High
Low
Low
AFS2
High
High
Low
Low
Summary of Contents for IC-706MKIIG
Page 1: ...SERVICE MANUAL HF VHF UHF ALL MODE TRANSCEIVER i706MK G ...
Page 58: ... HPF BOARD BOTTOM VIEW DRIVER BOARD BOTTOM VIEW 8 6 ...
Page 60: ... PA UNIT BOTTOM VIEW 8 8 ...
Page 62: ...1 8 16 9 PLL UNIT BOTTOM VIEW 8 10 ...
Page 64: ... FILTER BOARD BOTTOM VIEW 8 12 ...
Page 85: ...6 9 16 Kamihigashi Hirano ku Osaka 547 0002 Japan A 5564HI S C 1999 by Icom Inc ...