The most common reason for the the display to show only dots, is that one
of the phase locked loops is not locked. So take of the top cover. You will
be looking at the IF unit. This board is mounted in a hinged frame. It hinges
on two screws near the front pannel sides. So remove the other two screws
near the final unit instead and hinge the IF board towards you. You now
uncovered the PLL unit.
There are five PLL's on this board. Each one has a pin indicating if its
loop is locked or not. So get out a volt meter and set it for 5 volts full
scale. Now check pin 2 for each of the following IC's. IC18, IC1, IC4, IC9.
Also check pin 7 of IC17. If all the loops are locked, you would see a
steady voltage there in the neighbourhood of 4.7 volts. If any of the
loops is not locked, one of these pins has a voltage well below 1 volt.
Note the IC number so you can look up which VCO you may have to tune a bit
so it will lock again.
IC18 VCO#5 T20
IC1 VCO#4 T1
IC4 VCO#3 T2
IC9 VCO#2 T9
The above are all located on the PLL board.
The VCO for IC17 is actualy one out of four different VCO's selected
on the RF board. Which one of these depends on what band is selected.
If you have display dots on all the bands, then you have no problem
with the PLL made up with IC17. So you only have to adjust either
T1, T2, T9 or T20.
Now here it goes. Make sure you have an alignment tool that isn't to small
or to large for the slots in the slugs in the coils (T1, T2, etc.)
Also, absolutely don't turn any other coil than the one that belongs to the
unlocked PLL. If you do so anyway without a service manual and proper equip-
ment, then you are likely stupid.
Only turn the indicated slug. First turn it 1/4 clock wise and see if it is
ok now. If not, turn it 1/4 counter clockwise and see if it works. I suggest
that you don't try more than one half turn either way. If you think that it
needs to go that far, it likely has an other problem.
If the display dot problem only shows up on some but not all band, send me a
note and I will see if I can help you.
The correct way would be to use a good voltmeter and follow the service
manual for this adjustment. But in most cases, the above will do fine.
I don't work for Kwood, I don't have a 440. Just a service manual for one.
But I did cure some of the above problems.
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