Newsgroup: it.hobby.radioamatori
Titolo: r-5000 e circuito pll

ho un kenwood r-5000 che presenta il difetto sul circuito pll: la
frequenza che sparisce dal display e appaiono i puntini "....." al posto
di essa, e in piu' il segnale ricevuto sparisce come se l'antenna fosse
staccata dal ricevitore.
quanto puo' venire a costare una riparazione sul circuito pll? qualcuno sa
indicarmi una cifra approssimativa?
volevo portare il ricevitore a farlo riparare e non vorrei che mi
sparassero una cifra troppo elevata...
cordiali saluti,
giovanni
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Puoi provarci tu stesso. Il TS-440S è uguale all'R-5000:
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.
ciao,
Fil

Iil problema è ke non mi intendo assolutamente di componenti elettronici o
elettronica..non saprei proprio metterci le mani.
cmq x una riparazione del genere quanto potra' venire? partendo diciamo
dal piu' leggero dei casi fino ad peggiore dei casi con sostituzione di
tutto il circuito...100-200 euro o piu'??


 
be', dipende molto dall'onestà del riparatore. Non dovrebbe essere una 
cosa particolarmente difficile, il problema è il tempo che ci vuole.
D'altra parte un R-5000 si trova usato a 300-400 euro, per cui se ti 
chiedono più di 100-150 euro, secondo me è decisamente troppo.
ciao,
Fil