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3-7-18 RELAY CONTROLLER (RXPLL-B UNIT; IC1701)
7
HFOFB
Outputs the HF band’s pre-amplifier 2
control signal for the RX-B circuit.
High : The pre-amplifiers are OFF.
11
VP1B
Outputs the 50 MHz band’s pre-ampli-
fier 1 control signal for the RX-B cir-
cuit.
High : The pre-amplifier1 is ON.
12
HP2B
Outputs the HF band’s pre-amplifier 2
control signal for the RX-B circuit.
High : The pre-amplifier 2 is ON.
13
HP1B
Outputs the HF band’s pre-amplifier 1
control signal for the RX-B circuit.
High : The pre-amplifier 1 is ON.
14
VPOFB
Outputs the 50 MHz band’s pre-ampli-
fier control signal for the RX-B circuit.
High : The pre-amplifier is OFF.
Pin
Port
Description
number
name
3-7-19 RELAY CONTROLLER (RXPLL-B UNIT; IC1702)
4
HSEL
Outputs the 1st IF control signal for
the RX-B circuit.
High : While receiving on HF band.
5
VSEL
Outputs the 1st IF control signal for
the RX-B circuit.
High : While receiving on 50 MHz.
6
IFW
Outputs 1st IF filter (FI1401) select
signal for the RX-B circuit.
High : Select 16 kHz IF filter.
7
IFN
Outputs 1st IF filter (FI1402) select
signal for the RX-B circuit.
High : Select 6 kHz IF filter.
14
IFNN
Outputs 1st IF filter (FI1403) select
signal for the RX-B circuit.
High : Select 3 kHz IF filter.
Pin
Port
Description
number
name
3-7-20 BUFFER IC (MAIN UNIT; IC291)
12
TRVSM
Outputs the transmit signal switching
signal.
High : The transverter is ON.
13
SMUT
Outputs the SCOPE 3rd LO muting
signal.
High : While muting.
14
SSB
Outputs the scope IF signal switching
signal.
High : Input from the RX-B circuit.
15
SSA
Outputs the scope IF signal switching
signal.
High : Input from the RX-A circuit.
16
MONS
Outputs the transmitting monitor con-
trol signal.
High : Transmitting monitor is ON.
17
MCPS
Outputs modulation input signal con-
trol signal.
High : Input from the microphone or
ACC jack.
18
MMUT
Outputs the microphone mute control
signal.
High : While muting.
Pin
Port
Description
number
name
3-7-21 BUFFER IC (MAIN UNIT; IC311)
11
FMS
Outputs FM mode select signal.
12
UNSB
Outputs mode selecting signal other
than SSB and AM modes.
13
B_AFA
Outputs AF signals select signal.
High : While outputs AF signals to
the ACC-B connector.
14
A_AFA
Outputs AF signals select signal.
High : While outputs AF signals to
the ACC-A connector.
15
SPON
Outputs the internal speaker switching
signal.
High : While no headphones are
connected.
16
PMIX
Outputs phone L/R mixer control sig-
nal.
High : While mixing.
17
MAFS
Outputs AF signal selecting signal
from the MAIN pin or the SUB pin of
[MIC] jack.
High : The SUB pin is selected.
18
CROSS
Outputs receiver circuits switch signal
while split operating.
High : Set to [MAIN] to B-channel.
: Set to [SUB] to A-channel.
Pin
Port
Description
number
name
Summary of Contents for IC-7800
Page 1: ...SERVICE MANUAL ADDENDUM CONTENTS PARTS LIST 1 BOARD LAYOUTS 65 VOLTAGE DIAGRAM 67 Dec 2009 ...
Page 79: ...SERVICE MANUAL ADDENDUM CONTENTS PARTS LIST 1 BOARD LAYOUTS 60 VOLTAGE DIAGRAM 64 Feb 2009 ...
Page 157: ...SERVICE MANUAL ADDENDUM CONTENTS PARTS LIST 1 BOARD LAYOUTS 57 VOLTAGE DIAGRAM 59 Aug 2008 ...
Page 245: ...SERVICE MANUAL ADDENDUM CONTENTS PARTS LIST 1 BOARD LAYOUTS 57 VOLTAGE DIAGRAM 59 Jul 2008 ...
Page 333: ...THE TRANSCEIVER i7800 SERVICE MANUAL S 14015HZ C1 2 Mar 2006 ...
Page 555: ...1 1 32 Kamiminami Hirano ku Osaka 547 0003 Japan S 14015HZ C1 2 C 2004 2006 Icom Inc ...