Maintenance; Troubleshooting; Resetting The Cpu - Icom IC-R75 Instruction Manual

11

MAINTENANCE

Troubleshooting

The following chart is designed to help you correct
problems which are equipment malfunctions.
PROBLEM
Power does not come on
when the [POWER] switch
is pushed.
No sound comes from the
speaker.
Sensitivity is low.
Receive audio is distorted.
Programmed scan does
not stop.
Programmed scan does
not start.
Memory scan does not
start.
Select memory scan does
not start.
"F.AGC" flashes in the
function display.
The displayed frequency
does not change properly.

Resetting the CPU

[POWER]
36
POSSIBLE CAUSE
• DC power cable is improperly connected.
• Fuse is blown.
• Volume level is too low.
• The squelch is closed.
• The antenna is not connected properly.
• The antenna for another band is selected.
• The attenuator is activated.
• The operating mode is not selected correctly.
• PBT function is activated.
• Noise blanker function is activated.
• Preamp is activated.
• The optional noise reduction is activated and
the [NR] level is set too high.
• 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.
• A scan or band scope function is activated via
an optional RS-R75 remote control software.
• The dial lock function is activated.
• The internal CPU has malfunctioned.
[ZDN] [UPY]
If you are not able 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.
SOLUTION
• 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 MAIN unit.)
• Rotate [AF] clockwise to obtain a suitable
listening level.
• Rotate [RF/SQL] to 12 o'clock position to open
the squelch.
• Reconnect to the antenna connector.
• Select an antenna suitable for the operating
frequency.
• Push [ATT] to turn the function OFF.
• Select a suitable operating mode.
• Set [TWIN PBT] to the center position.
• Push [NB] to turn the function OFF.
• Push [P.AMP] once or twice to turn the function
OFF.
• Push [NR] to turn the function OFF.
• 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 channels P1 and P2.
• Program 2 or more memory channels.
• Designate 2 or more memory channels as select
channels for the scan.
• If these functions are not in use, push [AGC] to
deactivate the function.
• Push [LOCK] to deactivate the function.
• Reset the CPU.
Resetting CLEARS all programmed contents in
memory channels and returns programmed values
in set mode to their defaults.
When first applying power or when the function seems
to be displaying erroneous information, reset the CPU
as follows:
q Make sure receiver power is OFF.
w While pushing [UP Y] and [Z DN], push [POWER]
to turn power ON.
• The internal CPU is reset.
• The receiver displays its initial VFO frequencies when re-
setting is complete.
REF.
—
p. 37
p. 2
p. 14
—
p. 16
p. 16
p. 14
p. 15
p. 15
p. 16
p. 20
p. 14
pgs.
14, 30
p. 22
p. 22
p. 26
—
p. 13
See
below.