NO RF O/P : PA
If it is not PA (the most likely cause) then check diode D24 in
aerial switching, check for L2012 physically shorting to copper screen,
and check driver Q2021 and R69.
OFF FREQUENCY RX +- TX
If this is just a couple of KHz then realign PLL local osc. If it
is several KHz (possibly 10-12) off frequency then suspect PLL local
osc xtal X02 (18.7414MHz).
OFF FREQUENCY FM TX
ERRATIC FREQUENCY JUMPS
DRIFTING
Check -6.8v. rail, and check Q05 on REG unit if this is missing.
POOR SQUELCH OPERATION
POOR QUALITY FM RX
ERRATIC TUNING
TUNING JUMPS
INTERMITTENT TX+-RX
NO AUDIO O/P
Check audio IC Q1027. Also check to see if the reverse polarity
diode is blown, as reverse polarity causes failure of this IC.
CONTINUOUS CW OR NO CW TX
Check Q2010 (MC14001B). Also check the wire to the key socket is
not s/c or broken, as this can happen when the battery compartment is
taken in and out.
LOW SENSITIVITY RX
Check T1001 Ae. i/p coil, D25 in aerial switching and RF amp.
LOW SENSITIVITY ON A UNIT WITH A MUTEK BOARD
Check for loose strands from the braid of the Mutek board's coax
shorting out the connecting pins on the Mutek board. Then check BF980
in Mutek board.
FADING LCD DISPLAY
CRACKLING NOISE ON TX AUDIO (FM ONLY)
CRACKLING NOISE ON TX+-RX
MELTED NICADS
Replace DC i/p socket (and nicads). This fault can also occur as a
result of using a DC input plug which is not quite the correct
diameter or length, because the batteries are then not disconnected
when DC is plugged in.
POOR SSB TX (NON-LINEAR)
If the PA has gone non-linear, then replace the PA and change R70
from 390R to 270R.
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