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Hi all
I have seen many T28 suddendly dead. The phone doesn´t power on, not charge and is not detected by any program. What´s the problem of this phones? there is a factory fault? how it can be solved? I hear something about PA or some resistance, or something like this....
Any idea?
Regards
ReZn0r
100% right....
Common Problem is P Amp.
Rgds
Originally posted by ReZn0r:
<STRONG>Hi all
I have seen many T28 suddendly dead. The phone doesn´t power on, not charge and is not detected by any program. What´s the problem of this phones? there is a factory fault? how it can be solved? I hear something about PA or some resistance, or something like this....
Any idea?
Regards
ReZn0r</STRONG>
Hello ReZnOr...
It is very easy to find that weather it is PF problem..
U can check it without Opening the phone...
Just take the Multimeter, keep it on lover Resistance Mode and put the Pin on Battrey terminal(First pin of Handset from Both Side).. and check the Meter Indication.Now change the Polarities (Interchange the Meter Pin and Battrey Terminal Contacts) and check the Meter Indication. If the meter shows Indication in Both procedure then your PF is Short... Remove it.. Your Phone will ON now, but no network..
Now put new OK pf there and your Phone should be Work...(Be carefull in placing PF again.. otherwise it will Short Again)..
Easy...
:) :) :)
themobileking
07-11-2001, 16:26
Dear friend
take the advice given by the guys before me
BBand is really good at ericsson
the pfo is short 95% of the time on all dead T28 sets
regards the mobileking
Hanukkah
07-13-2001, 02:37
What if there is still movement in the multi tester after the Power Amp is removed? I have one unit that doesn't power on, I've removed the PA and still doesn't power on. I've just repacked the power IC and reinstalled it to no avail. What could be other areas to check. Thanks
Originally posted by Hanukkah:
<STRONG>What if there is still movement in the multi tester after the Power Amp is removed? I have one unit that doesn't power on, I've removed the PA and still doesn't power on. I've just repacked the power IC and reinstalled it to no avail. What could be other areas to check. Thanks</STRONG>
Hi Hanukkah...
Well this problem is solved...
Do this things...
Check the REsistors, Inductors and Capcitor near Left site of PF... Sometime they also Bcomes short... Do this after Reomoving PF..
Little bit time consuming work but u can slove your problem...
Good Luck
:) :) :)
Hi Guyz,
What method do you guys use to removed PF, can this be done with a soldering iron ?
Does n e 1 have data sheet for this chip ?
Where can I get new PF ?
Many THx
DocX
<FONT COLOR="#ffff00" SIZE="1">[ 13 July 2001 12:53: Message edited 1 time, lastly by DocX ]</font>
Thx for ALL the answers. The problem is very clear now.
:) :) :)
Regards
ReZn0r
Hanukkah
07-14-2001, 20:32
Originally posted by DocX:
<STRONG>Hi Guyz,
What method do you guys use to removed PF, can this be done with a soldering iron ?
Does n e 1 have data sheet for this chip ?
Where can I get new PF ?
Many THx
DocX</STRONG>
Use a hot air rework station. Sorry I don't have data sheet for the pfo. Maybe someone from the forum has. Good Luck
gsmmsngr
07-15-2001, 13:22
How to solder the new PF back into the original position ? Someone advised to use thin wires extended from PCB to make connection without putting the PF back in it's original position, but this makes it very clumsy ! :eek: :rolleyes: :p
Hanukkah
07-30-2001, 03:19
[quote]Originally posted by gsm_boy:<br /><strong>
Hi Hanukkah...
Well this problem is solved...
Do this things...
Check the REsistors, Inductors and Capcitor near Left site of PF... Sometime they also Bcomes short... Do this after Reomoving PF..<br />Little bit time consuming work but u can slove your problem...
Good Luck
<img src="smile.gif" border="0"> <img src="smile.gif" border="0"> <img src="smile.gif" border="0"></strong><hr></blockquote>
Hi Gsm_boy,
I've just removed the capacitors and inductors 1 by 1 and checked them. The capacitors are ok. The resistors too, and so with the inductor. What else could be the problem? Another observation is that the phone allows charging of the battery. Pls. help. Thanks!
Pandemonio100
07-30-2001, 21:41
To Hanukkah your problem don't is only the P.A. but also you have to change power Ic in BGA mode near the oscillator (1011102/3CR1B). <br />Very difficult change this component, you should possess a welder to infrared (ERSA IR500 the BEST)since there are too little balls under the component to solder. <img src="wink.gif" border="0">
hi friends,<br />this forum is really wonderful, if i have any problem, i can always find solution in history :-)<br />...but now my problem is, that i need some P.Amp. (abou 3-5p.) and i dont know where can i buy it and how much it cost, pleaz if anyone of you can give me some informations, write me!! <img src="rolleyes.gif" border="0"> <br />thanx...
Platy