Troubleshooting; D Transceiver Power; D Transmit And Receive - Icom IC-7700 Instruction Manual

13
MAINTENANCE

■ Troubleshooting

D D Transceiver power
PROBLEM
Power does not come on
when the [POWER] switch
is pushed.
D D Transmit and receive
PROBLEM
No sounds from the
speaker.
Sensitivity is too low, and
only strong signals are
audible.
Received audio is unclear
or distorted.
The [ANT] switch does not
function
Transmitting is impossible.
Output power is too low.
No contact can be made
with another station.
Transmit signal is unclear
or distorted.
Repeater cannot be
accessed.
POSSIBLE CAUSE
• Power cable is improperly connected.
• The internal power supply is turned OFF.
• Circuit breaker is tripped.
POSSIBLE CAUSE
• Volume level is too low.
• The squelch is closed.
• The transceiver is in transmit.
• 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 inside a ham
band.
• [RF PWR] is set too far counterclockwise
• [DRIVE] is set too far counterclockwise
• [MIC] 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 is activated.
• [MIC] is set too far clockwise
• Split frequency function is not activated.
• Programmed subaudible tone frequency is
wrong.
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 you near-
est Icom Dealer or Service Center.
SOLUTION
• Re-connect the AC power cable correctly.
• Turn the internal power supply ON.
• Check for the cause, then re-set the circuit
breaker.
SOLUTION
• Rotate [AF] clockwise to obtain a suitable lis-
tening level.
• Turn [SQL] to 10 o'clock position to open the
squelch.
• Push [TRANSMIT] to receive or check the
SEND line of an external unit, if connected.
• Re-connect to the antenna connector.
• Select an antenna suitable for the operating
frequency.
• Push and hold [TUNER] for 1 sec. to manually
tune the antenna.
• Push [ATT]
(MF4)
OFF."
• Select a suitable operating mode.
• Push and hold [PBT-CLR] for 1 sec. to reset the
function.
• Push [NB] to turn the noise blanker OFF.
• Push [P.AMP]
(MF3)
function OFF.
• Set the [NR] control for maximum readability.
• Set the antenna switch in set mode to "Auto" or
"Manual."
• Set the frequency to be in a ham band.
• Rotate [RF PWR] clockwise.
• Set [DRIVE] to a suitable position.
• Set [MIC] to a suitable position.
• Select an antenna suitable for the operating
frequency.
• Push and hold [TUNER] for 1 sec. to manually
tune the antenna.
• Push [RIT] or [∂TX] to turn the function OFF.
• Push [SPLIT] to turn the function OFF.
• Set [MIC] to a suitable position.
• Push [SPLIT] to to turn the function ON
• Reset the frequency using set mode.
13-2
several times to select "ATT
once or twice to turn the
REF.
p. 2-5
p. 3-2
—
REF.
p. 3-9
p. 3-9
p. 3-12
—
p. 10-2
p. 10-6
p. 5-9
p. 3-8
p. 5-12
p. 5-16
p. 5-9
p. 5-17
p. 10-4
p. 3-5
p. 3-12
p. 3-13
p. 3-12
p. 10-2
p. 10-6
pgs. 5-10,
6-4
p. 6-6
p. 3-12
p. 6-6
p. 4-33