FT480 faults
                   ============

DISTORTION ON SSB TX : Check PA. If there is no O/P in FM low power position
then PA is very suspect.

NO RF O/P WHEN HOT : Check PA.

NO LOW POWER FM TX : Suspect PA.

LOW SENSITIVITY RX : Check RF stage - if this is OK check Ae i/p coil T01 for
o/c. See next fault.

INTERMITTENT TX AND RX : Check TX/RX 8v. switching relay. Check 10.24MHz xtal
in PLL.

LOW POWER TX AND/OR POOR RX : Check relay and xtal as above.

FLUCTUATIONS IN OUTPUT POWER : Check PA. Check relay and xtal as above. Also
check the power control transistor Q03 in the PA screened box.

RX FAILS WHEN PTT RELEASED : Check TX/RX 8v. switching relay.

ERRATIC FREQUENCY SHIFTS : Check X02 63.9151MHz xtal in PLL.

ERRATIC OPERATION OF TUNING CONTROL : Step switch.

SUDDEN JUMPS IN FREQUENCY WHEN TUNING IN SSB : X02 - as above.

NO AUDIO : Check audio output IC.

DISPLAY ON WHEN UNIT TURNED OFF : Check D34 on the microprocessor control
board.

INTERMITTENT AUDIO ON TX : Check the mic gain and deviation presets as these
can become dirty/cracked.

TONE CALL BUTTON APPEARS INOPERATIVE : Many owners have disconnected this
button and used it to provide a 'listen on input' facility.

STRANGE FREQUENCY READOUT : Check microprocessor, especially if one digit is
brighter than the rest.

ALL EIGHTS ON FREQUENCY DISPLAY : DC power applied to rig when rig is
switched on - this problem can be alleviated by changing C01 - the power-up
reset cap (on control unit, connected to pin 24 of microprocessor) to a
larger value (0.47uF tantalum). Also check microprocessor.


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