Icom IC-718 Two-Way Radio User Manual


 
10
52
MAINTENANCE
n Troubleshooting
The following chart is designed to help you correct
problems which are equipment malfunctions.
If you are not able to locate the cause of a problem
or solve it through the use of this chart, contact your
nearest Icom Dealer or Service Center.
PROBLEM POSSIBLE CAUSE SOLUTION REF.
DISPLAY
POWER
RECEIVE
TRANSMIT
SCAN
Power does not come on
when the [POWER] switch
is pused.
No sounds comes from
the speaker.
Sensitivity is low.
Receive audio is distorted.
Transmitting is impossible.
Output power is too low.
No contact possible with
another station.
Transmitted signals are
distorted.
Programmed scan does
not stop.
Programmed scan does
not start.
Memory scan does not
start.
The displayed frequency
does not change prooerly.
p. 12
p. 53
p. 2
p. 2
p. 6
p. 3
p. 3
p. 20
p. 21
p. 21
p. 22
p. 23
p. 17
p. 42
p. 42
p. 10
p. 3
p. 21
pgs. 7,
31, 32
p. 2
p. 27
p. 3
p. 30
p. 40
p. 40
p. 6
p. 41
p. 53
• Reconnect the DC power cable correctly.
Check for the cause, then replace the fuse
with a spare one.
(Fuses are installed in the DC power cable
and the internal PA unit.)
• Rotate [AF] clockwise to obtain a sutable lis-
tening level.
• Rotate [RF/SQL] to 10 o’clock position to open
the squelch.
Check the SEND line of an external unit, if de-
sired.
• Reconnect to the antenna connector.
• Connect an antenna suitable for the operating
frequency.
• Push [TUNER] for 2 sec. to manually tune the
antenna.
• Push [ATT] to select “ATT” OFF.
• Select a suitable operating mode.
• Rotate the SHIFT control to center position.
• Push [NB] to turn the function OFF.
• Push [P.AMP] to turn the function OFF.
• Set the [NR] control for maximum readability.
• Set the frequency to a ham band.
• Set [RF POWER] to a suitable position.
• Set [MIC GAIN] to a suitable position.
Select an antenna suitable for the operating
frequency.
• Push [TUNE] for 2 sec. to manually tune the
antenna.
• Push [RIT] to turn the function OFF.
• Push [SPLIT] to turn the function OFF.
• Set [MIC GAIN] to a suitable position.
• Turn [COMP] OFF.
• Set [RF/SQL] to the threshold point.
• Reset [RF/SQL] control assigned and set it to
the threshold point.
Program different frequencies in scan edge
memory channels P1 and P2.
• Program 2 or more memory channels.
• Push [LOCK] to deactivate the function.
• Push [SET] to exit the quick set mode.
• Reset the CPU.
• DC power cable is improperly connected.
• Fuse is blown.
• Power supply not turned ON.
• Volume level is too low.
• The squelch is closed.
The transceiver is in the transmitting condition.
• The antenns is not connected properly.
• The antenna is for another band is connected.
• The antenna is not properly tuned.
• The attenuator is activated.
• The operating mode is not selected correctly.
• IF SHIFT function is activated.
• Noise blanker function is activated.
• Preamp is activated.
• The noise reduction is activated and the [NR]
control is set too high.
• The operating frequency is not set to a ham
band.
• [RF POWER] is set too low.
• [MIC GAIN] is set too low.
• The antenna for another band is selected.
• The antenna is not properly tuned.
• RIT function is activated.
• Split frequency function is activated.
• [MIC GAIN] too high.
• [COMP] function is activated.
• 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.
• The dial lock function is activated.
• A quick set mode screen is selected.
• The internal CPU has mulfunctioned.