Icom Ic-78 Hf Tranciever Instruction Manual

							9
3INSTALLATION AND  CONNECTIONS
nRequired connections
PWR
MICROPHONES (p. 45)
SM-20or SM-6,
     SM-8 HM-36
GROUND (p. 8)
Use the heaviest gauge wire 
or strap available and make 
the connection as short as 
possible.
Grounding prevents electrical 
shocks, TVI and other 
problems.
ANTENNA  
[Example]: 1.8–30 MHz bandsDC POWER SUPPLY
PS-85
CW KEY
A straight key can be used when the 
internal electronic keyer is turned 
OFF in “CW PADDL” in 
initial  set 
mode
. (p. 32)
AH-710
¥ Front panel
¥ Rear panel 
						

							10
3INSTALLATION AND  CONNECTIONS
nPower supply connections
Use an optional PS-85DC POWER SUPPLYwhen operat-
ing the IC-78 with AC power. Refer to the diagrams
below.
CAUTION:Before connecting the DC power cable,
check the following important items. Make sure:
¥ The [PWR] switch is OFF.
¥ Output voltage of the power source is 12Ð15 V
when you use a non-Icom power supply.
¥ DC power cable polarity is correct.
Red : positive +terminal
Black : negative _terminal
CONNECTING A VEHICLE BATTERY
12 V
battery
Supplied
DC power cable+ red
_ blackCrimp
Solder
Grommet
NEVER connectto
a 24 V battery.NOTE:Use terminals for
the cable connections.
CONNECTING NON-ICOM DC POWER SUPPLY
DC power 
socketDC power supply
AC outlet
AC cable
20 A fuses Supplied
DC power cable13.8 V  20 A
_
+
black
red
+ _
CONNECTING PS-85 DC POWER SUPPLY
PS-85
Connect to an AC outlet
using the supplied AC cable.
DC power cable
DC power
socket 
						

							3INSTALLATION AND  CONNECTIONS
11
nAdvanced connections
PWRMIC
The AFSK modulation signal can be 
input from [MIC]. (p. 25)
HEADPHONES
¥ Front panel
ANTENNA
Connects a linear amplifier, etc.
[REMOTE] (pgs. 41, 42)
Used for computer control and transceive operation,
and cloning operation between transceivers.
[SEND], [ALC] 
Used for connecting a 
non-Icom linear ampli-
fier.EXTERNAL SPEAKER (p. 44)
SP-21, etc.
ACC SOCKETS (p. 6)
AT-120, 
AT-130, or
AH-4 (p. 44)
AH-2b
or long wire with
¥ Rear panel 
						

							3INSTALLATION AND  CONNECTIONS
12
nExternal antenna tuners
CONNECTING AN ANTENNA TUNER (p. 44)
Coaxial cable (from the tuner)Long wire or optional AH-2b
Ground IC-78
AT-120/AT-130/AH-4
Control cable
Ground 
						

							4OPERATION
13
nSelecting a channel
The transceiver has 99 memory channels. However,
the number of channels can be restricted in 
initial set
mode
(p. 32) depending on your needs. A total of 3
ways of channel selections are available to suit your
operating style.
DUsing the channel selector
Rotate the channel selector clockwise (channel num-
ber increases) or counterclockwise (channel number
decreases) to select desired channel.
This is the most useful way of channel selection.
DUsing up/down switches
Push [ÃDN]/[UPº] on the front panel or the micro-
phone to select the desired channel.
This way is convenient when changing a small num-
ber of channels.
¥ When a duplex channel (different frequencies be-
tween transmit and receive) is selected, Ò Ó ap-
pears. 
DUsing the keypad
Enter the number of the desired channel number using
the keypad (0 to 9), then push [ENT].
This way is convenient for remembering the usage and
stored channel number, or when changing large a
number of channels.
¥ When a duplex channel (different frequencies be-
tween transmit and receive) is selected, Ò Ó ap-
pears. 
¥ When a blank channel (no frequency is programmed)
is selected, Ò Ó appears. 
Channel 1
Channel 2
Channel 99
Rotate the 
channel selector
Push [Ã DN]/[UP º] 
switch
to select a 
channelor
• Example 1— selecting channel 8
PushPush
PushPush Blinks
• Example 2— selecting channel 25
Push
Blinks
Blinks 
						

							4OPERATION
14
nFrequency indication
By pushing the [FC], channel comment indication or
frequency indication can be selected.
DTransmit frequency indication
By pushing the [TXF], transmit frequency is indicated,
regardless channel comment or frequency indication.
While transmit frequency is indicated, Ò Ó ßashes.
nLock function
The lock function electronically locks the main dial to
prevent accidental channel changing.
Push [LOCK] to turn the lock function ON and OFF.
Before channel selection, turn this function OFF.
nScan function
Scan function repeatedly scans programmed chan-
nels. This function is convenient to wait for calls on
multiple channels.
qSet [RF/SQL] control at the center (12 oÕclock) po-
sition (opening squelch), then rotate [RF/SQL]
control clockwise to the position where the noise
disappears.wPush [ÃDN] or [UPº] for 1 sec. to start channel
scan.
¥ The ÒSCANÓ indicator appears.
eWhen a signal is received, channel scan pauses
on that channel.
rPush [ÃDN] or [UPº] to cancel channel scan.
NOTE:The scan resume condition (the action
after signal receiving) can be selected as Òscan re-
sumeÓ or Òscan cancelÓ in the 
initial set mode
(p. 31).
[
à DN]/[UP 
º]
switches
Appears while lock function is activated.
Appears while
scanning.
ch 5 ch 2 ch 3 ch 4
ch 6 ch 7BLANK
BLANKch 1
ch 99
Shallow
DeepRecommended
position
Squelch control
Channel indication
Frequency indication
Push
Push
Push
Transmit frequency indication
Flashes 
						

							15
4OPERATION
nMode selection
The [RF/SQL] control adjusts either the RF gain or
the squelch. The action depends on the operating
mode and the condition of the RF/SQL item in 
initial
set mode
(p. 31).
¥ [RF/SQL] control priority
* The RF gain is set to maximum level when the [RF/SQL]
is set as [SQL] control.
The RF gainis used to adjust the receiver gain.
¥ Shallow rotation moves the S-meter to the right indicating
the signal strength which can be received.
The recommended position for RF gain is the 12
oÕclock position since this sets RF gain to the max.
The 
SQUELCHremoves noise output from the
speaker 
(closed condition)when no signal is received.
The squelch is available for the other modes.
¥ A segment appears in the S-meter to indicate the S-meter
squelch level.
¥ When set as the [RF/SQL] control
¥ When set as the [SQL] control
¥ When set as the [RF] control
nRF gain and Squelch
Set mode setting SSB, CW, RTTY AM
rS (RF/SQL) RF/SQL RF/SQL
At (Auto) RF gain SQL*
Sq (SQL)
SQL* SQL*
(default)
RF gain adjustable
range Maximum RF gain
Squelch is open.
S-meter squelch
S-meter squelch
threshold
Squelch is open.
S-meter squelchS-meter squelch
threshold
Shallow Deep
Minimum RF gain Adjustable range Maximum RF gain
nBasic voice receive and transmit
qCheck the following in advance:
åMicrophone is connected.
å[AF] control is set to minimum position.
å[RF/SQL] is set to center position (squelch open).
å[RIT] control set to center position.
w
Selects the desired channel to be received with the
channel selector, [
ÃDN]/[UPº], or 10-key pad.
¥The S-meter shows signal strength when signal is received.
eAdjust [AF] to the desired audio level when receiv-
ing a signal.
rPush [MODE] to select the desired operation mode,
if the received signal is in a different mode.
tIf the bass or treble of the receive audio is too
strong, rotate [RIT] control to obtain clear audio.
(p. 19)
y
Push [TUNER] to tune the antenna tuner, if connected. 
¥ ÒTUNEÓ indicator ßashes for 1 to 2 sec. for the Þrst tun-
ing on a channel.
uPush and hold [PTT] on the microphone, and speak
into the microphone at a normal voice level.
¥ The RF meter shows the output power according to your
voice level, when RF power meter is selected.
iRelease [PTT] to return to receive.
[
RIT]
[
AF]
[RF/SQL] Microphone
connector
The following modes are available in the IC-78:
SSB (LSB/USB), CW, CW REV (CW reverse), RTTY,
RTTY REV (RTTY reverse) and AM.
åPush [MODE] to select desired operation mode.
åPush [MODE] for 1 sec. to change between USB
and LSB, CW and CW reverse or RTTY and RTTY
reverse. (SSB, CW and RTTY mode only)
¥ The selected mode is indicated in the function display.
Note:The selected mode can be used for temporary
operation only. OPERATING MODE SELECTION
Push
momentarily
Push
for 1 sec. USB LSB
CW CW
RTTY RTTY
AM
MODE
MODE 
						

							16
4OPERATION
•Meter function
The bar meter in the function display acts as an S-
meter (for relative signal strength) during receive and
can be selected for one of three functions during
transmit.
¥ Push [SET] to select the PO, ALC and SWR meter
mode.
¥ Measuring SWR
qConÞrm that the output power is over 30 W.
wPush [SET] to select the SWR meter.
ePush [MODE] to select CW or RTTY operation.
¥ Key down or push [PTT] to transmit; then read the ac-
tual SWR from the meter:
²1.5; well matched antenna
³1.5; check antenna or cable connection, etc.
Display
Measurement
Indication
POIndicates the relative RF output power.
ALCIndicates the ALC level. When the meter
movement shows the input signal level ex-
ceeds the allowable level, the ALC limits the
RF power. In such cases, reduce the micro-
phone gain (see above).
SWRIndicates the SWR over the transmission line.
nFunctions for transmit
•Output power and microphone gain
¥ Setting output power
qPush [SET] for 1 sec. to select 
quick set mode.
wPush [ºUP]/[ÃDN] to select ÒRF POWERÓ.
eRotate the main dial to select the desired output.
¥ Output power is displayed in 101 steps (L, 1Ð99 and H)
but is continuously selectable.
¥ Available power
SSB/CW/RTTY: 2 (or less) to 100 W
AM : 2 (or less) to 40 W*
*Carrier power
Maximum output
power is selected.¥ Setting microphone gain
Microphone gain must be adjusted properly so that
your signal does not distort when transmitted.
qSelect SSB or AM mode.
wPush [SET] for 1 sec. to enter the quick set mode.
ePush [ºUP]/[ÃDN] to select ÒMIC GAINÓ.
rAdjust the mic gain while speaking into the micro-
phone, so that the ALC meter does not exceed the
ALC zone.
tPush [SET] to exit 
quick set mode.
Microphone gain
is set to 50.
ALC zone
The best match is in this range. 
						

							17
4OPERATION
•Microphone compressor
IC-78 has a built-in, low distortion Mic compressor
circuit. This circuit increases your average talk power
in SSB mode and is especially useful when the re-
ceiving station is having difÞculty copying your signal.
qSelect USB or LSB mode.
wPush [COMP] switch to turn mic compressor ON.
¥ ÒCOMÓ indicator appears.
eConÞrm the ALC level.
¥ Push [SET] to select the ALC meter.
¥ Speak into the microphone at a normal voice level.
¥ If the ALC meter peak past the ALC zone, re-adjust the
mic. gain. (p.16)
¥ Be sure the mic gain is in the range of 20 to 50.
Note:When the ALC meter peaks above the ALC
zone, your transmitted voice may be distorted.
The VOX (Voice-operated Transmission) function
switches between transmit and receive with your
voice. This function provides an opportunity to input
log entries into your computer, etc. while operating.
qSelect ÒVOXÓ in 
quick set mode.
¥ Push [SET] for 1 sec. to select quick set mode.
¥ Push [ºUP]/[ÃDN] to select ÒVOXÓ.
wRotate the channel selector to turn VOX function
ON.eSelect ÒVOX GAINÓ in 
quick set mode.
¥ Push [ºUP]/[ÃDN] to select ÒVOXÓ.
rWhile speaking into the microphone, adjust [VOX
GAIN] with the channel selector, until the trans-
ceiver is transmitting.
tSelect ÒVOX DELYÓ in 
quick set mode.
¥ Push [ºUP]/[ÃDN] to select ÒVOX DelayÓ
tWhile speaking into the microphone, adjust [VOX
DELY] as desired.
ySelect ÒANTI-VOXÓ in 
quick set mode.
¥ Push [ºUP]/[ÃDN] one or more times to select ÒAN
VOXÓ
uIf the receive audio from the speaker switches the
transceiver to transmit during receive, adjust the
ÒANTI-VOXÓ to the point where it has no effect.
iPush [SET] to exit 
quick set mode.
•VOX operation
Rotate the 
channel selector
ON OFF
[COMP] switchAdjust [MIC GAIN] so that the ALC 
meter reads within the ALC zone.ALC zone
Appears when 
mic compressor 
is activated. 
						

							18
4OPERATION
The AT-120, AT-130 or AH-4 matches the IC-78 to a
long wire antenna more than 7 m 
(23 ft)long (3.5 MHz
and above).
¥ See p. 11 for connection.
¥ See the connected antenna tunerÕs instruction man-
ual for installation and antenna connection details.
¥ Setting example:
NEVERoperate  the AT-120, AT-130  or AH-4  without
an antenna wire. The tuner and transceiver will be
damaged.
NEVERoperate the AT-120, AT-130 or AH-4 when it
is ungrounded.
Transmitting before tuning may damage the trans-
ceiver. Note that the AT-120, AT-130 or AH-4 cannot
tune when using a 
1Ú2llong wire or multiple of the op-
erating frequency.TUNER OPERATION
¥ Tuner type setting (p. 32)
qPush [PWR] for 1 sec. to turn power OFF.
wEnter 
initial set mode.
¥ Turn power ON while pushing and holding [SET].
ePush [UPY] or [ZDN] to select [TUNER].
rSelects connected antenna tuner type by rotating
the channel selector.
¥ no : no antenna tuner is selected.
¥ 4 : AH-4 is selected.
¥ 12 : AT-120 is selected.
¥ 13 : AT-130 is selected.
yPush [PWR] for 1 sec. to turn power OFF.
uPush [PWR] to turn power ON again.
¥ MANUAL TUNING
qSet the desired channel.
wPush [TUNER] to start tuning.
¥ Ò Ó blinks and ÒCWÓ appears while tuning.
eÒÓlights constantly when tuning is completed.
(except when AT-120 is connected; the indicator
goes out)
¥ When the connected wire cannot be tuned, the Ò Ó
goes out, the antenna tuner is bypassed and the an-
tenna wire is connected to the antenna connector on
the transceiver directly.
rTo bypass the antenna tuner manually, push
[TUNER]. (AH-4 only; starts tuning again when AT-
120 or AT-130 is connected)
For mobile operation    
For outdoor operation    
Long wireOptional AH-2b
antenna element
MICIC-718
PHONESSQL   AFSHIFT  RITLOCKMODEFILTERTSPWRTUNERº
º
COMPP.AMPUP NB
AT TSET
CHDNENT F-INPV/M1MW4A=B2M =CL5SCN8ANF0NR.A/B3VOX9 7SPLM V6ÛAT-120
AT-130
AH-4
R R
WARNING: HIGH VOLTAGE!
NEVER touch the antenna element while tuning or
transmitting.
Tuning is required for each frequency. Be sureto
re-tune the antenna before transmitting when you
change the frequencyÑ even slightly.
[TUNER] switch
•Optional AT-120/AT-130/AH-4 operation
Tuning indicator;
Blinks: While tuning
Appears: Tune is completed
Disappears: Tune is not completed
(When AT-120 is connected, the 
indicator disappears even when 
tuned  completely.)