Icom Ic_r20 Communications Reciever Instruction Manual

							18
4
BASIC OPERATION
4
■Squelch level settingThe squelch circuit mutes the received audio signal depend-
ing on the signal strength. The receiver has 9 squelch levels,
a continuously open setting and an automatic squelch setting.
➥While pushing and holding [SQL], rotate [R-DIAL]to se-
lect the squelch level.
•“LEVEL 1” is loose squelch and “LEVEL 9” is tight squelch.
•“AUTO” indicates automatic level adjustment with a noise pulse
count system.
•“OPEN” indicates continuously open setting.
■Monitor functionThis function is used to listen to weak signals without disturb-
ing the squelch setting or to open the squelch manually even
when mute functions such as the tone squelch are in use.
➥Push and hold [SQL]to monitor the operating frequency.•The 1st segment of the S-meter blinks.The [SQL]key can be set to ‘sticky’ operation in expanded
set mode. See page 54 for details.
√MODE
ANLAFC TSQL
FM
146010
PSKIP
-DUP
The 1st segment blinks
SQL
SQUELCH:AUTO√MODE
ANLAFC TSQL
FM
146010
PSKIP
-DUP
SQUELCH:LEVEL9√MODE
ANLAFC TSQL
FM
146010
PSKIP
-DUPAutomatic squelch
Maximum level [R-DIAL]
SQL 
						

							■Attenuator functionThe attenuator prevents a desired signal from distorting when
very strong signals are near the desired frequency or when
very strong electric fields, such as from a broadcasting sta-
tion, are near your location. The attenuator gain is about 30
dB.
➥Push 
[Ω ΩΩ
Ω
ATT]
for 1 sec. to toggle the attenuator function
ON and OFF.
•“ATT” appears when the attenuator function is in use.
■RF gainThe receiver gain can be reduced with the RF gain setting.
This may help to remove undesired weak signals while mon-
itoring strong signals. The RF gain may be useful for setting a
minimum level at which to hear signals for SSB/CW modes .
➥Push [
≈
≈≈
≈
RF GAIN]
for 1 sec. to enter the RF gain setting
condition, then rotate [R-DIAL]to select the desired RF
gain level.
•Normally this setting is used with maximum level.
•Push [DUALWATCH]to exit the RF gain setting condition.
SET-RF-GAIN:MAX√MODE
ANLAFC TSQL
USB14120
PSKIP
-DUP
SET-RF-GAIN:5√MODE
ANLAFC TSQL
USB14120
PSKIP
-DUPMaximum level
Setting level5 [R-DIAL]
RF GAIN
ATT√MODE
ANLAFC TSQL
FM
146010
PSKIP
-DUP
AT T
DIAL.SEL SWEEP CENTER
T-SCAN SKIP M.N
TONE SET TS
ATTRF GAIN
IC Recorder
123
4560
789BANDDUALWATCH
MAIN/SUB
POWER
VFO
MHzMODE
SCANMR
S.MW
SCOPE
LOCK
RECAFC
“ATT” appears while the 
attenuator functions is in 
use.
19
4
BASIC OPERATION 
						

							20
4
BASIC OPERATION
4
Duplex communication uses 2 different frequencies for trans-
mitting and receiving. Generally, duplex is used in communi-
cation through a repeater, some utility communications, etc.
During duplex operation, the transmit station frequency is
shifted from the receive station frequency by the offset fre-
quency. Repeater information (offset frequency and shift di-
rection) can be programmed into memory channels. (p. 26)D D
SettingqSet the receive station frequency 
(repeater output frequency)
.
wPush [8 SET]for 1 sec. to enter set mode.
eRotate [R-DIAL]to select “SET EXPAND,” then push
[8 SET].rRotate [R-DIAL]to select “ON,” then push [8 SET].
tRotate [R-DIAL]to select “OFFSET FREQ,” then push
[8 SET].
yRotate [R-DIAL]to set the desired offset frequency within
0.00000–159.99999 MHz range, then push [8 SET].
•The tuning step, selected in VFO mode, is used for setting.
•Push [VFO MHz]for 1 sec. then rotate [R-DIAL]to change the
frequency in 1 MHz steps, or push for 1 sec. again then rotate
[R-DIAL]to change the frequency in 10 MHz steps. (Each push
for 1 sec. toggles 1 MHz or 10 MHz tuning steps.)uRotate [R-DIAL]to select “DUPLEX.”
iRotate [R-DIAL]to select “–DUP” or “+DUP.”
oPush [DUALWATCH]to exit set mode.
!0Push and hold [SQL]to monitor the transmit station fre-
quency 
(repeater input frequency)
directly.
DUPLEX
--DUP >OFF
-+DUP ----------------OFFSET-FREQ
----0.000.00 ----------------
[R-DIAL]DUALWATCHSET8
SET TS:5.0kHz√MODE
ANLAFC TSQL
FM
146 010
PSKIP
-DUP
***-SET-MODE-***
>SET-EXPAND -FM-ANTENNA -AM-ANTENNA -AF-FILTER -ANL -NOISE-BLANKER ----------------
■Duplex operation
INEXPANDED SET MODE 
						

							21
4
BASIC OPERATION
■AFC functionThe AFC (Automatic Frequency Control) function tunes the
displayed frequency automatically when an off-center fre-
quency is received. It activates in FM/WFM modes only with
single band operation.
➥Push 
[0 AFC]
to toggle the AFC function ON and OFF.
•“AFC” appears when the AFC function is in use.NOTE: The AFC function is not available during dualwatch
operation.
■NB/ANL functionThe NB (noise blanker) function removes pulse-type noise
when USB, LSB or CW mode is selected. The ANL (Auto-
matic Noise Limitter) function reduces noise components
when AM mode is selected.
See page 22 for setting details.
NOTE:No display indication appears during dualwatch op-
eration, but both functions are active while in specific
modes.
√MODE
ANLAFC TSQL
AM51100
PSKIP
-DUP
√MODE
NBAFC TSQL
USB
145100
PSKIP
-DUP“NB” appears while the
 NB function is in use.
“ANL” appears while the
 ANL function is in use.
ATT√MODE
ANLAFCTSQLFM
1260000
PSKIP
-DUP
DIAL.SEL SWEEP CENTER
T-SCAN SKIP M.N
TONE SET TS
ATTRF GAIN
IC Recorder
123
4560
789BANDDUALWATCH
MAIN/SUB
POWER
VFO
MHzMODE
SCANMR
S.MW
SCOPE
LOCK
RECAFC
“AFC” appears while the 
AFC function is in use.
0AFC
“    ”  “    ” or
an off-frequency is received.appears when  
						

							22
4
BASIC OPERATION
4
■Band scopeThe band scope function allows you to visually check a spec-
ified frequency range. Sweep range can be selected from
±14kHz through ±1400 kHz.
qSet the desired frequency as band scope center frequency.
wWhile pushing and holding [2 SWEEP], rotate [R-DIAL]to
select the sweep steps, if desired.
•Available steps are 1, 5, 6.25, 8.33, 9, 10, 12.5, 15, 20, 25, 30,
50 and 100 kHz.
•Pushing [2 SWEEP]changes the sweep step and starts single
sweeping at each times.
ePush [SCOPE]momentarily to start single sweeping or
push for 1 sec. to start continuous sweeping. 
•Signal conditions (strengths) appear starting from the center of
the range.
rRotate [R-DIAL]to set the highlighted cursor to the de-
sired waveform and set the frequency of the signal.
•Push [3 CENTER]for 1 sec. to return to original sweep center
frequency.
tPush [DUALWATCH]to cancel sweeping and return to
normal condition. ✔CONVENIENT!
The scope function can also be started with the following op-
eration for easy setting.
qSet the desired frequency as band scope center frequency.
wPush [2 SWEEP]for 1 sec. to start single sweeping.•Pushing [2 SWEEP]changes the sweep step and starts singlesweeping at each times.
√MODE
ANLAFC TSQL
FM
145780
PSKIP
SWEEP
10k
-DUPSWEEP
10k
[R-DIAL]SCOPECENTER3SWEEP2
Sweep marker
Sweep step
Sweep indicationBand scope indication 
						

							23
4
BASIC OPERATION
■[DIAL] function assignmentThe frequency control dial can be traded with an audio volume
control dial or [Y Y
]/[Z Z
]keys to suit your preference. ➥Push [1 DIAL.SEL]for 1 sec. to toggle the dial function
from tuning dial and audio volume.
•Single band operation
•Dualwatch operation
√MODE
ANLAFC TSQL
FM
146560
PSKIP
-DUP∂145250438000AFC
-DUP -DUP
FM
TSQL TSQL
PS PS
PRIO PRIO
FM000 000
00 00
FM
[R-DIAL]
[L-DIAL]DIAL.SEL1
“ ” indication “ ” indication
• Frequency, Memory chan-
nel, Squelch level, Scan-
ning direction for upper
band
• Set mode item and condi-
tion set for MAIN band
• Frequency, Memory chan-
nel, Squelch level, Scan-
ning direction for lower
band
• Set mode item and condi-
tion set for MAIN band
Audio volume set for MAIN
band [L-DIAL]
[R-DIAL][Y]/[Z]Audio volume set for upper
band
Audio volume set for lower
band
Frequency, Memory chan-
nel, Squelch level, Scanning
direction, Set mode item
and condition set for MAIN
band
“ √ √
” indication “ ∂ ∂
” indication
Frequency, Memory chan-
nel, Squelch level, Scanning
direction, Set mode item
and condition set
Audio volume set
[R-DIAL][L-DIAL]
[Y]/[Z]Audio volume set
Frequency, Memory chan-
nel, Squelch level, Scanning 
direction, Set mode item
and condition set 
						

							24
5
DUALWATCH OPERATION
45
■Main band selection➥Push [MAIN/SUB]momentarily to select the upper band
or lower band as main band (operating band) alternately.
■Band exchange➥Push [MAIN/SUB]for 1 sec to exchange the upper band’s
frequency and lower band’s frequency.
• The A-side is upper side on the display, and B-side is
lower side, if the band exchange function (see above) is
not performed (default).
• Available frequency bands are different depending on
version. See the specification for details.
• *Some frequency ranges are prohibited for the USA ver-
sion due to local regulation.
145 000
433 000AFC
-DUP -DUP
FM
TSQL TSQL
PS PS
PRIO PRIO
LSB
000 000
00 00
145250438000AFC
-DUP -DUP
FM
TSQL TSQL
PS PS
PRIO PRIO
FM000 000
00 00
438000145250
-DUP -DUP
FM
TSQL TSQL
PS PS
PRIO PRIO
FM000 000
00 00
PS PS
MAIN/SUB
145 000
433 000AFC
-DUP -DUP
FM
TSQL TSQL
PS PS
PRIO PRIO
LSB
000 000
00 00
145250438000AFC
-DUP -DUP
FM
TSQL TSQL
PS PS
PRIO PRIO
FM000 000
00 00
145250438000
-DUP -DUP
FM
TSQL TSQL
PS PS
PRIO PRIO
FM000 000
00 00
PS PS
MAIN/SUB
Band A-side B-side
1 M✔–
AM (BC)✔–
HF bands✔–
FM (BC)✔–
VHF air✔✔
144 MHz✔✔
Band A-side B-side
300 MHz✔✔
400 MHz✔✔
800 MHz* –✔
1.2 GHz –✔
2.4 GHz – –
• Operating bands table for dualwatch operation 
						

							25
5
DUALWATCH OPERATION
■Setting audio volumeqPush [DUALWATCH]for 1 sec. to enter the dualwatch op-
eration, if necessary
wPush and hold [SQL], p
ush [Y Y
]or [Z Z
]to adjust the audio
level for the main band. 
•Pushing and holding either key changes the audio level continu-
ously.
•The display shows the volume level while setting.While pushing either 
[Y Y
]or [Z Z
]
, rotate [L-DIAL]for upper
band’s volume adjustment, or [R-DIAL]for lower band’s
volume adjustment.
■Squelch level settingqPush [DUALWATCH]for 1 sec. to enter the dualwatch op-
eration, if necessary
wWhile pushing and holding [SQL], rotate [L-DIAL]for
upper band’s squelch adjustment, or rotate [R-DIAL]for
lower band’s squelch adjustment.
•“LEVEL 1” is loose squelch and “LEVEL 9” is tight squelch.
•“AUTO” indicates automatic level adjustment with a noise pulse
count system.
•“OPEN” indicates continuously open setting.
145 000
433 000AFC
-DUP -DUP
FM
TSQL TSQL
PS PS
PRIO PRIO
LSB
000 000
00 00
145250438000AFC
-DUP -DUP
FM
TSQL TSQL
PS PS
PRIO PRIO
FM000 000
00 00
PS PS PS
SQUELCH:LEVEL9438
.000
SQUELCH:AUTO
PS
145
.250
[R-DIAL] [L-DIAL]SQL
Upper band setting
Lower band setting
145250438000AFC
-DUP -DUP
FM
VOLVOLTSQL TSQL
PS PS
PRIO PRIO
FM000 000
00 00
145250438000
PS PS000 000
Upper band setting
Lower band setting
SQL 
						

							26
6
MEMORY CHANNELS
■General descriptionThe receiver has 1050 memory channels including 50 scan
edge memory channels (25 pairs) for storage of often-used
frequencies. And a total of 26 memory banks, A to Z are avail-
able for usage by group, etc. Up to 100 channels can be as-
signed into a bank.D D
Memory channel contentsThe following information can be programmed into memory
channels:
•Operating frequency (p. 14)
•Receive mode (p. 16)
•Duplex direction (+DUP or –DUP) with an offset fre-
quency (p. 20)
•Tone squelch or DTCS squelch ON/OFF (p. 45)
•Tone squelch frequency or DTCS code with polarity
(p. 46)
•Scan skip information* (p. 39)
■
Memory channel programming
qPush [VFO MHz]to select VFO mode.
wSet the desired frequency:
➥Select the desired band with [BAND].
➥Set the desired frequency with [R-DIAL].
➥Or set the desired frequency with [KEYPAD].
➥Set other data 
(e.g. offset frequency, duplex direction, tone
squelch, etc.)
, if desired.
ePush [MR S.MW]for 1 sec. to select the select memory
write condition.
•1 short and 1 long beep sound.
•“µ µ
” indicator blinks.
rRotate [R-DIAL]to select the desired channel.
•Scan edge channel, 00A/B to 24A/B can also be selected.
tPush [MR S.MW]for 1 sec.
•3 beeps sound
•Memory channel number automatically increases when contin-
uing to push [MR S.MW]after programming.
[EXAMPLE]:Programming 145.870 MHz into memory channel 20 (blank channel).√
µ
MODE
ANLAFC TSQL
TSQL
FMFM
145870
PSKIP
-DUP
-DUP
001
√
µ
MODE
ANLAFC TSQL
TSQL
FM
145870
PSKIP
-DUP
-DUP
020
√
µ
MODE
ANLAFC TSQL
TSQL
FM
145870
PSKIP
-DUP
-DUP
020
>CLEAR
CLEAR -SKIP
SKIP-:OFF
:OFF -MNAME:
MNAME: -BNAME: -BNAME: -BANK
BANK-:----
:----001 001
µ
.
146
.010
FM>CLEAR
CLEAR -SKIP
SKIP-:OFF
:OFF -MNAME:
MNAME: -BNAME: -BNAME: -BANK
BANK-:----
:----020 020
µ
. ---------------- ----------------
Push             for 1 sec.
Rotate
MR
S.MW
Push             for 1 sec.
MR
S.MW
56 
						

							27
6
MEMORY CHANNELS
■Memory bank settingThe IC-R20 has a total of 26 banks 
(A to Z)
. Regular memory
channels, 000 to 999, are assigned into the desired bank for
easy memory management.
qPush [MR S.MW]for 1 sec. to select the select memory
write condition.
•1 short and 1 long beep sound.
•“µ µ
” indicator blinks.
wRotate [R-DIAL]to select the desired memory channel.
eWhile pushing [8 SET], rotate [R-DIAL]to select “BANK.”
•“BANK” item can also be selected by pushing [8 SET]several
times.•Bank group and channel number is displayed if the selected mem-
ory channel has already been previously assigned into a bank.
rWhile pushing [BAND], rotate [R-DIAL]to select the de-
sired bank group from “A” to “Z.”
•The bank group can also be selected by pushing [BAND]sev-
eral times.
tAfter releasing [BAND], rotate [R-DIAL]to select the bank
channel number from “00” to “99.”
•Vacant bank channel numbers will only be displayed.
yPush [MR S.MW]for 1 sec. to set the channel into the
bank.
•Return to the previous indication.
-BNAME:FM>BANK-:A-00012
µ
.
146
.010
Bank channel is selected with [R-DIAL]-BNAME:FM>BANK-:A-00012
µ
.
146
.010
Bank group is selected with 
BAND
FM>CLEAR -SKIP-:OFF -MNAME: -BNAME:
-BANK-:----012
µ
.
146
.010
FM>BANK-:----012
µ
.
146
.010
is pushed After [R-DIAL]
SET8
SET8
MR
S.MWBAND
SET TS:5.0kHz√MODE
ANLAFC TSQL
FM
146 010
PSKIP
-DUP