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15
107
MAINTENANCE
SCAN
■
Troubleshooting
The following chart is designed to help you correct
problems which are not equipment malfunctions.
If you are unable to locate the cause of a problem or
solve it through the use of this chart, contact your near-
est Icom Dealer or Service Center.
PROBLEM
POSSIBLE CAUSE
SOLUTION
REF.
RECEIVE
POWER
TRANSMIT
Power does not come on
when the
[POWER]
switch
is pushed.
No sounds come out from
the speaker.
Sensitivity is too low, and
only strong signals are au-
dible.
Received audio is unclear
or distorted.
The
[ANT]
switch does not
function.
Transmitting is impossible.
Output power is too low.
You can receive signals,
but no contact possible
with another station.
Transmit signal is unclear
or distorted.
Repeater cannot be ac-
cessed.
Programmed scan does
not stop.
Programmed scan does
not start.
Memory scan does not
start.
Select memory scan does
not start.
• Power cable is improperly connected.
• Fuse is blown.
• Volume level is too low.
• The squelch is closed.
• The transceiver is in transmitting condition.
• The antenna is not connected properly.
• The antenna for another band is selected.
• The antenna is not properly tuned.
• The attenuator is activated.
• Wrong operating mode is selected.
• PBT function is activated.
• Noise blanker is turned ON when receiving a
strong signal.
• Preamp is activated.
• The noise reduction is activated and the
[NR]
control is too far clockwise.
• The antenna switch has not been activated.
• The operating frequency is not set to a ham
band.
•
[RF POWER]
is set too far counterclockwise
•
[MIC GAIN]
is set too far counterclockwise
• The antenna for another band is selected.
• The antenna is not properly tuned.
• RIT or
∂
TX function is activated.
• Split frequency function and/or dualwatch are
activated.
•
[MIC GAIN]
is set too far clockwise.
• The speech compressor function is activated.
• Split frequency function is not activated.
• Programmed subaudible tone frequency is set
at wrong frequency.
• Squelch is open.
•
[RF/SQL]
is assigned to RF gain control and
squelch is open.
• The same frequencies have been programmed
in scan edge memory channels P1 and P2.
• 2 or more memory channels have not been
programmed.
• 2 or more memory channels have not been
designated as select channels.
• Re-connect the DC power cable correctly.
• Check for the cause, then replace the fuse with
the spare one.
(Fuses are installed in the DC power cable and
the internal PA unit.)
• Rotate
[AF]
clockwise to obtain a suitable lis-
tening level.
• Turn
[RF/SQL]
to 10 o’clock position to open
the squelch.
• Push
[TRANSMIT]
to receive or check the
SEND line of an external unit, if desired.
• Re-connect to the antenna connector.
• Select an antenna suitable for the operating fre-
quency.
• Push
[TUNER]
for 1 sec. to manually tune the
antenna.
• Push
[ATT]
several times to select “ATT OFF.”
• Select a suitable operating mode.
• Push
[PBT CLR]
for 1 sec. to reset the function.
• Push
[NB]
to turn the noise blanker OFF.
• Push
[P.AMP]
once or twice to turn the function
OFF.
• Set the
[NR]
control for maximum readability.
• Set the antenna switch in set mode to “Auto” or
“Manual.”
• Set the frequency to a ham band.
• Rotate
[RF POWER]
clockwise.
• Set
[MIC GAIN]
to a suitable position.
• Select an antenna suitable for the operating fre-
quency.
• Push
[TUNER]
for 1 sec. to manually tune the
antenna.
• Push
[RIT]
or
[
∂
∂
TX]
to turn the function OFF.
• Push
[SPLIT]
and/or
[DUALWATCH]
to turn the
function OFF.
• Set
[MIC GAIN]
to a suitable position.
• Push
[COMP]
to turn the function OFF.
• Push
[SPLIT]
to turn the function ON
• Reset the frequency using set mode.
• Set
[RF/SQL]
to the threshold point.
• Reset
[RF/SQL]
control assignment and set it to
the threshold point.
• Program different frequencies in scan edge
memory channel P1 and P2.
• Program more than 2 memory channels.
• Designate more than 2 memory channels as se-
lect channels for the scan.
p. 16
p. 108
p. 1
p. 2
p. 1
—
pgs. 3,
88
p. 89
p. 3
p. 29
p. 60
p. 64
p. 3
p. 65
p. 88
p. 25
p. 2
p. 1
p. 3
p. 89
p. 6
pgs. 8,
63, 71
p. 1
p.68
p. 8
p. 52
p. 2
pgs. 2,
30, 99
p. 79
p. 79
pgs. 78,
86