Icom Ic-78 Hf Tranciever Instruction Manual

							INSTRUCTION MANUAL
HF TRANSCEIVER
i78
This device complies with Part 15 of the FCC rules. Operation is sub-
ject to the following two conditions: (1) This device may not cause
harmful interference, and (2) this device must accept any interference
received, including interference that may cause undesired operation. 
						

							IMPORTANT
READ THIS INSTRUCTION MANUAL
CAREFULLY
before attempting to operate the
transceiver.
SAVE THIS INSTRUCTION MANUAL.This
manual contains important safety and operating in-
structions for the IC-78.
EXPLICIT DEFINITIONS
i
PRECAUTIONS
RWARNING HIGH VOLTAGE! NEVERat-
tach an antenna or internal antenna connector during
transmission. This may result in an electric shock or
burn.
RNEVERapply AC to the [DC13.8V] jack on the
transceiver rear panel. This could cause a Þre or ruin
the transceiver.
RNEVERapply more than 16 V DC, such as a 24 V
battery, to the [DC13.8V] jack on the transceiver rear
panel. This could cause a Þre or ruin the transceiver.
RNEVERlet metal, wire or other objects touch any
internal part or connectors on the rear panel of the
transceiver. This may result in an electric shock.
NEVERexpose the transceiver to rain, snow or any
liquids.
AVOIDusing or placing the transceiver in areas with
temperatures below Ð10¡C (+14¡F) or above +60¡C
(+140¡F). Be aware that temperatures on a vehicleÕs
dashboard can exceed 80¡C (+176¡F), resulting in per-
manent damage to the transceiver if left there for ex-
tended periods.
AVOIDplacing the transceiver in excessively dusty en-
vironments or in direct sunlight.
AVOIDplacing the transceiver against walls or putting
anything on top of the transceiver. This will obstruct
heat dissipation.
During mobile operation, DO NOToperate the trans-
ceiver without running the vehicleÕs engine. When the
transceiver power is ON and your vehicleÕs engine is
OFF, the vehicleÕs battery will soon become ex-
hausted.
Make sure the transceiver power is OFF before start-
ing the vehicle. This will avoid possible damage to the
transceiver by ignition voltage spikes.During maritime mobile operation, keep the transceiver
and microphone as far away as possible from the mag-
netic navigation compass to prevent erroneous indica-
tions.
BE CAREFUL!The heatsink will become hot when op-
erating the transceiver continuously for long periods.
BE CAREFUL!If a linear amplifier is connected, set
the transceiverÕs RF output power to less than the lin-
ear ampliÞerÕs maximum input level, otherwise, the lin-
ear ampliÞer will be damaged.
Use Icom microphones only (supplied or optional).
Other manufacturerÕs microphones have different pin
assignments, and connection to the IC-78 may dam-
age the transceiver.WORD DEFINITION
RWARNINGPersonal injury, Þre hazard or electric
shock may occur.
CAUTIONEquipment damage may occur.
NOTEInconvenience only. No risk of per of
personal injury, Þre or electric shock. 
						

							1
1
TABLE OF CONTENTS
q
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er
IMPORTANT .............................................................. i
EXPLICIT DEFINITIONS ........................................... i
PRECAUTIONS ........................................................ i
1 TABLE OF CONTENTS  ....................................... 1
SUPPLIED ACCESSORIES  ..................................... 1
2 PANEL DESCRIPTION ................................... 2 Ð 7
nFront panel  ....................................................... 2
nFunction display  ............................................... 4
nRear panel  ........................................................ 5
nMicrophone (HM-36)  ........................................ 7
3 INSTALLATION AND CONNECTIONS  ......... 8 Ð 12
nUnpacking ........................................................ 8
nSelecting a location  .......................................... 8
nGrounding ......................................................... 8
nAntenna connection .......................................... 8
nRequired connections ....................................... 9
nPower supply connections .............................. 10
nAdvanced connections .................................... 11
nExternal antenna tuners  ................................. 12
4 OPERATION ................................................. 13Ð 27
nSelecting a channel ......................................... 13
nFrequency indication ....................................... 14
nLock function ................................................... 14
nScan function................................................... 14
nBasic voice receive and transmit ..................... 15
nMode selection ................................................ 15
nRF gain and Squelch ....................................... 15
nFunctions for transmit ...................................... 16
nFunctions for receive ....................................... 19
nFilter selection ................................................. 21
nFilter setting ..................................................... 22
nFunctions for CW............................................. 23
nFunctions for RTTY ......................................... 25
nChannel comment programming ..................... 27
5 SET MODE ................................................... 28Ð 33
nGeneral............................................................ 28
nQuick set mode items ...................................... 29
nInitial set mode items....................................... 316 EXTRA FEATURES ...................................... 34Ð 36
nInstruction ........................................................ 34
nVFO operation ................................................. 34
n2-Tone alarm operation ................................... 36
7 INSTALLATION AND CONNECTIONS ........ 37Ð 38
nOpening the transceiverÕs case  ...................... 37
nOptional bracket and carrying handle.............. 37
nCR-338 HIGH STABILITY CRYSTAL UNIT......... 38
nOptional IF Þlters  ............................................ 38
8 MAINTENANCE ........................................... 39Ð 40
nTroubleshooting .............................................. 39
nFuse replacement ........................................... 40
nResetting the CPU .......................................... 40
9 REMOTE JACK INFORMATION .................. 41Ð 42
nCI-V remote control ......................................... 41
nData cloning between transceivers ................. 42
10 SPECIFICATIONS ........................................... 43
12 OPTIONS .................................................. 44Ð 45
SUPPLIED ACCESSORIES
The transceiver comes with the following accessories.
Qty.
qDC power cable .................................................... 1
wHand microphone (HM-36)  .................................. 1
eFuse (FGB 20 A; for DC cable) ............................ 1
rFuse (FGB 4 A; internal use)  ............................... 1 
						

							nFront panel 
qPOWER SWITCH [PWR]
å
Push momentarily to turn power ON.
¥ Turn the optional DC power supply ON in advance.
åPush for 1 sec. to turn power OFF.
åWhile pushing and holding [SET], push [PWR] to
enter the 
initial set mode. (p. 28)
wMICROPHONE CONNECTOR [MIC]
Accepts supplied or optional microphone.
¥ See p. 45 for appropriate microphones.
¥ See p. 7 for microphone connector information.
eHEADPHONE JACK [PHONES](p. 11)
Accepts headphones.
¥ When headphones are connected, the internal
speaker or connected external speaker does not
function.
rAF CONTROL [AF](inner control)
Varies the audio output level from the speaker.
tRF GAIN/SQUELCH CONTROL [RF/SQL] 
(outer control; pgs. 15, 31)
Adjusts the squelch threshold level. The squelch re-
moves noise output from the speaker (closed con-
dition) when no signal is received.
¥ The squelch is available for all modes.
¥ The control can be set as the squelch plus RF gain
controls or squelch control only (RF gain is Þxed at
maximum) in initial set mode.
yRIT CONTROL [RIT](inner control; p. 19)
åShifts the receive frequency ±1.2 kHz for clear re-
ception of an off frequency signal. 
¥ Rotate the control clockwise to increase the fre-
quency, or rotate the control counterclockwise to
decrease the frequency. Ò Ó appears on the
display.uIF SHIFT CONTROLS [SHIFT] 
(outer control; p. 20)
Shifts the center frequency of the receiverÕs IF
passband.
¥ Rotate the control clockwise to shift the center fre-
quency higher, or rotate the control counterclock-
wise to shift the center frequency lower.
iLOCK SWITCH [LOCK](p. 14)
Push momentarily to turn the dial lock function ON
and OFF.
¥ The dial lock function electronically locks the chan-
nel selector.
oCHANNEL SELECTOR
Selects an operating channel, sets conditions in the
quick/initial set mode items, etc.
!0PREAMP SWITCH [P.AMP](p. 19)
Push to turn the preamp ON or OFF.
!1FC SWITCH [CH]
åPush to change the indication, channel comment
or stored frequency. (p. 14)
*This key action only for some versions.
å
Push for 1 sec. to entering into VFO mode. (p. 35)
!2MEMORY CHANNEL UP/DOWN SWITCHES
[
ÃDN]/[UPº]
åPush to select the operating channel. (p. 13)
åPush for 1 sec. to start scanning. (p. 14)
åPush to select the 
quick/initial set modeitems
while 
quick/initial set modeis selected. (p. 28)
åPush to select the digit of channel comment while
editing. (p. 27)
2
2
PANEL DESCRIPTION
PWR
SpeakerFunction Display@1@0!9!7
!5
!4
!6
!3
!2
!0
!8
!1oiuytr e
w
q 
						

							3
2PANEL DESCRIPTION
!3ATTENUATOR SWITCH [ATT](p. 19)
Push to turn the 20 dB attenuator function ON and
OFF.
!4TUNER SWITCH [TUNER] (p. 18)
åPush to turn the antenna tuner function ON and
OFF.
åPush for 1 sec. to manually tune the tuner.
¥ An optional antenna tuner must be connected.
¥ When the tuner cannot tune the antenna, the tun-
ing circuit is bypassed automatically after 20 sec.
!5SET SWITCH [SET]
åPush for 1 sec. to enter the 
quick set mode.
(p. 28)
åPush and hold [SET], then push [PWR] to enter
the 
initial set mode. (p. 28)
åPush to change the meter function; (p. 16)
¥ PO: indicates the relative RF output power.
¥ ALC: Indicates ALC level.
¥ SWR: Indicates the SWR over the transmission
line.
!6MIC COMPRESSOR SWITCH [COMP](p. 17)
Turn the Mic. compressor function ON and OFF.
!7KEYPAD
The keypad can be used for several functions as
described below:
å[0] to [9]
Ñ For entering operating channel number. (p. 13)
Ñ Selects a character during channel comment
programming. (p. 27)
å[ENT]
Ñ Direct channel number input. (p. 13)
å[TXF]
Ñ Transmit frequency indication. (p.14)
Ñ Selects a space and changes the editing digit
during channel comment programming. (p. 27)
!8NOISE BLANKER SWITCH [NB](p. 19)
åTurns the noise blanker ON and OFF. The noise
blanker reduces pulse-type noise such as that
generated by automobile ignition systems. This
function is not effective against non pulse-type
noise.
åPush [NB] for 1 sec. to enter the noise blanker
level setting condition.
!9TONE SWITCH [TONE]
*
This key action may differ according to version.
åSelects the call channel and emits a distress
alarm tone from the speaker. (p. 36)
åTransmits a distress alarm or alarm testing signal
when pushed for 1 sec. (p. 36)
¥ Cancel the distress alarm tone emission, or dis-
tress alarm transmission.
åSelects the tuning step item in the 
quick set mode
directly.
åNo function is assigned.@0CALL SWITCH [CALL]
åPush to select call channel.
¥ Push again to return to previous condition.
@1MODE SWITCH [MODE](p. 15)
Push to change an operating mode.
¥ Push [MODE] for 1 sec. during SSB mode to
switch between LSB or USB.
¥ Push [MODE] for 1 sec. during CW or RTTY
mode, to switch between CW and CW reverse or
RTTY and RTTY reverse. Ò Ó appears on the
display. 
						

							4
2PANEL DESCRIPTION
nFunction display
qLOCK INDICATOR(p. 14)
Appears when the dial lock function is in use.
wRECEIVE INDICATOR
Appears while receiving a signal or when the
squelch is open.
eTUNE INDICATOR
åAppears or disappears when the connected au-
tomatic tuner is tuned completely, depending on
connected antenna tuner type.
åFlashes while tuning.
rTRANSMIT INDICATOR
åAppears while transmitting.
åFlashes while transmit frequency is indicated.
tALARM INDICATOR
*This indicator appears only some versions.
Appears while 2-tone alarm is emitting or transmit-
ting
yFUNCTION INDICATORS 
åÒP.AMPÓ appears when preamp is activated.
åÒATTÓ appears when the RF attenuator is acti-
vated.
åÒNBÓ appears when the Noise Blanker is acti-
vated.
åÒBKÓ appears when the semi break-in function is
selected in 
quick set mode.
åÒF-BKÓ appears when the full break-in function
activates in CW mode. (p. 23)
åÒVOXÓ appears when the VOX function is se-
lected in 
quick set mode.
åÒCOMÓ appears when the speech compressor ac-
tivates in SSB mode.
åÒSCANÓ appears during scanning.
¥ Flashes when scan is paused.
uSIGNAL/SQL/RF-GAIN METER
åFunctions as an S-meter while receiving.
åFunctions as a Power, ALC or SWR meter while
transmitting. (p. 16)iVFO/MEMORY INDICATOR
åÒMEMOÓ appears during regular operation.
*This indicator appears only some versions.
åÒVFOÓ appears during VFO operation.
oCHANNEL NUMBER READOUT(p. 13)
Shows the selected channel number. 
!0BLANK INDICATOR
Appears when no frequency programmed channel
is selected.
!1SPLIT INDICATORS(p. 13)
Appears when the duplex channel, in which differ-
ent frequencies between transmit and receive are
programmed, is selected.
!2RIT INDICATOR(p. 19)
Appears when the RIT function is in use.
!3CHANNEL READOUT
Shows the memory names, or stored frequency of
the selected channel.
!4REVERSE INDICATOR(p. 15)
Appears when the CW reverse or RTTY reverse
mode is selected.
!5WIDE/NARROW FILTER INDICATORS(pgs. 21, 22)
åÒ Ó appears when the wide IF Þlter is selected.
åÒ Ó appears when the narrow IF filter is se-
lected.
!6MODE INDICATORS(p. 15)
Indicates the temporarily selected operating mode.
!6!4!5
uoi
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w
!0
!3
!1 t
y
q
!2 
						

							5
2PANEL DESCRIPTION
nRear panel
qANTENNA TERMINAL [ANT](p. 9)
Connects a 50 ½antenna with a PL-259 connector
and a 50 ½coaxial cable.
wDC POWER SOCKET [DC 13.8V](p. 10)
Accepts 13.8 V DC through the supplied DC power
cable.
eTUNER CONTROL SOCKET [TUNER](p. 11)
Accepts the control cable from an optional antenna
tuner.
rREMOTE JACK [REMOTE](p. 11)
For use with a personal computer for remote opera-
tion of transceiver functions, and data cloning be-
tween transceivers.
tEXTERNAL SPEAKER JACK [EXT SP]
Connects an 8 ½external speaker, if desired.
¥ When an external speaker is connected, the inter-
nal speaker does not function.
yACCESSORY SOCKET [ACC](p. 6)
Enables connection to external equipment such as
a TNC for data communications or a linear ampli-
Þer, etc.uELECTRONIC KEYER JACK [KEY]
Accepts a paddle to activate the internal electronic
keyer.
¥ Selection between the internal electronic keyer
and straight key operation can be made in initial
set mode.
iALC INPUT JACK [ALC]
Connects to the ALC output jack of a non-Icom lin-
ear ampliÞer.
oSEND CONTROL JACK [SEND]
Goes to ground while transmitting to control exter-
nal equipment such as a linear ampliÞer.
¥ Max. control level: 16 V DC/2 A
!0GROUND TERMINAL [GND](p. 9)
Connects the terminal to ground.
qwe
r t y u i o !0
Rear panel view
When connecting
a straight key
When connecting
a paddle
(dot)
(com)
(dash)(Å) 
						

							6
2PANEL DESCRIPTION
D D
ACC SOCKET INFORMATION
¥ ACC socket
¥ When connecting the ACC conversion cable (OPC-599)
ACC PIN # NAME DESCRIPTION SPECIFICATIONS
ACC 1
ACC 2
À FSKKÄ AF
Á GNDÅ SQLSÂ SENDÆ 13.8 V
à MODÇ ALC
À 8 VÄ ALC
Á GNDÅ NCÂ SENDÆ 13.8 V
à BAND
11
22
33
44
88
77
66
55
9
10 11 1213
12
3 4
7 65
Rear panel
view
12348 7 6 5 9
10 11 1213
1 8 V Regulated 8 V output.Output voltage : 8 V ±0.3 V
Output current : Less than 10 mA
2 GND Connects to ground. Ñ
Input/output pin.
Ground level : Ð0.5 V to 0.8 V
3 SEND Goes to ground when transmitting.
Input current : Less than 20 mA
When grounded, transmits.
4 BDT Data line. Ñ
5 BAND Band voltage output.
6 ALC ALC voltage output.Control voltage : Ð4 V to 0 V
Input impedance: More than 10 k½
7NC Ñ Ñ Ñ
8
13.8 V13.8 V output when power is ON. Output current : Max. 1 A
9 TKEY Key line. Ñ
10 FSKK RTTY key input.Ground level : Ð0.5 V to 0.8 V
Input current : Less than 10 mA
11 MOD Modulation input.
Input impedance: 10 k½
Input level : Approx. 100 mV rms
12 AFAF detector output.
Output impedance: 4.7 k½
Fixed, regardless of [AF] position. Output level : 100Ð300 mV rms
13 SQLSSquelch output. SQL open : Less than 0.3 V/5 mA
Goes to ground when squelch opens.SQL closed : More than 6.0 V/100 µA 
						

							7
2PANEL DESCRIPTION
nMicrophone (HM-36)
¥ DESCRIPTION
qUP/DOWN SWITCHES [UP]/[DN]
Change the selected readout frequency or memory
channel.
¥ Continuous pushing changes the frequency or
memory channel number continuously.
¥ The [UP]/[DN] switch can simulate a key paddle.
Preset in the CW PADDL in initial set mode. (p. 32)
wPTT SWITCH
Push and hold to transmit; release to receive.
¥ MICROPHONE CONNECTOR 
(Front view)
CAUTION: DO NOT short pin 2 to ground as this
can damage the internal 8 V regulator.
q
w
y GND (PTT ground)
t PTT
r Main readout squelch switch q Microphone input
w +8 V DC output
e Frequency up/downu GND 
(Microphone ground) i Main readout AF output 
(varies with [AF])
¥ HM-36 SCHEMATIC DIAGRAM
+ +
q
w
e
rty u
i
4700 p 4700 p 10 µ
0.33 µ
MICROPHONE
MIC
ELEMENT
2 k
470
DOWN UP
PTT
RECEIVE
TRANSMIT
MICROPHONE CABLE MICROPHONE PLUG
[MIC]
FUNCTION DESCRIPTION
Pin No.
w+8 V DC output Max. 10 mA
eFrequency up Ground
Frequency down Ground through 470½
rSquelch open ÒLowÓ level
Squelch closed ÒHighÓ level 
						

							3
8
INSTALLATION AND CONNECTIONS
nAntenna connection
For radio communications, the antenna is of critical impor-
tance, along with output power and sensitivity. Select an-
tenna(s), such as a well-matched 50 ½antenna, and feed
line. 1.5:1 or better of Voltage Standing Wave Ratio (VSWR)
is recommended for your desired band. Of course, the trans-
mission line should be a coaxial cable.
CAUTION: Protect your transceiver from lightning
by using a lightning arrestor.
nUnpacking
After unpacking, immediately report any damage to the
delivering carrier or dealer. Keep the shipping cartons.
For a description and a diagram of accessory equip-
ment included with the IC-78, see ÔSupplied acces-
soriesÕ on p. 1 of this manual.
nSelecting a location
Select a location for the transceiver that allows ade-
quate air circulation, free from extreme heat, cold, or
vibrations, and away from TV sets, TV antenna ele-
ments, radios and other electro-magnetic sources.
The base of the transceiver has an adjustable stand
for desktop use. Set the stand to one of two angles de-
pending on your operating conditions.
nGrounding
To prevent electrical shock, television interference
(TVI), broadcast interference (BCI) and other prob-
lems, ground the transceiver through the GROUND
terminal on the rear panel.
For best results, connect a heavy gauge wire or strap
to a long earth-sunk copper rod. Make the distance be-
tween the [GND] terminal and ground as short as pos-
sible.
RWARNING: NEVERconnect the [GND]
terminal to a gas or electric pipe, since the connec-
tion could cause an explosion or electric shock.
Antenna SWR
Each antenna is tuned for a specified frequency
range and SWR may be increased out-of-range.
When the SWR is higher than approx. 2.0:1, the
transceiverÕs power drops to protect the Þnal transis-
tor. In this case, an antenna tuner is useful to match
the transceiver and antenna. Low SWR allows full
power for transmitting even when using the antenna
tuner. The IC-78 has an SWR meter to monitor the
antenna SWR continuously.
PL-259 CONNECTOR INSTALLATION EXAMPLE
30 mm Å9Ú8in   10 mm Å3Ú8in   1Ð2 mm Å1Ú16in
30 mm
10 mm (soft solder)
10 mm
1–2 mm
solder solderSoft
solder Coupling ringSlide the coupling ring 
down. Strip the cable 
jacket and soft solder.
Slide the connector 
body on and solder it.
Screw the coupling 
ring onto the 
connector body. Strip the cable as 
shown at left. Soft sol-
der the center con-
ductor.q
w
e
r