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Hp laptop adapter fail

What is causing the noise in the video and how to fix
Suddenly the lap stop working and i get that noise the adapter didn't make output dc to run the laptop
After I disassemble it and recorded the video i was checking it and i tried to plug it again to the electricity the noise stopped but it's Still not working





 

davenn

Moderator
After I disassemble it and recorded the video i was checking it and i tried to plug it again to the electricity the noise stopped but it's Still not working

I can hear what sounds like birds chirping and maybe a very faint tick tick tick ......

sounds like it's in a shutdown mode
check the electro caps in the DC output side
 
How to check it?

I watched that video
I disconnect the cord it was shorted
But still don't get the 19v when i measures the output connectors
I think something not working


Tell me how to check the caps
 
check the wires. the wires sometimes break on the device end, and have to be cut and spliced. I had one that was busted on both ends., I had to rewire the plug and the board. There is alot of white pucky in there. That's quite a bit of white pucky. Might call it a pucky covered mother!
 
i measure away of the wires...i measure on the board the ac in it's 220 v and i measure the dc out on the board is none 0
 
DSC_0360.jpg



all the red circuit units is working

why no output dc

the one at the right bottom corner is a fuse
 
Sir pharaon . . . . . . . .


OK here I am looking at this unit and starting a side by side working PCB side to FOIL side drawing comparison and you come up with your last info.

I then add it to the bottom and identify your circled units, which you claim as working . . . . but being uncertain of your manner of that confirmation.

If you are correct, there should be 19VDC across your LV storage capacitors at the left of the page, THEN that voltage gets routed on over to the output wiring.

If that voltage is NOT at the output connector, then see if repeated use and flexure . . . over time . . . has not broken all the wires inside the insulation on either wires internal conductors..

When you get down to 3 or so strands trying to carry 19VDC at ~ 5 amps the wires can vaporize then arc at every flexed closure and arc and vaporize open an even WIDER wire gap.

Or if that voltage is NOT at the final LV storage caps, your earlier stage circuitry is not working.

Tell us the part numbering of the 16 pin flat pack SMPS controller that this unit is using.

Also, might as well give the two LVPS sections two 8 pin IC’s numbers also . . . . and if exploration evolves to it . . . might need to take a pointed wooden sucker stick and abrade off the LARGE blob of white “pookey” that is covering a large area of the foil pattern. (Little nearby clear blob says . . . .me too . . .ME TOO ! )

You say:

The output caps is 680 mf and my voltmeter support 200 mf measurement only

Associated . . . Timely TechnicalTip . . . .on instrumentation:
.
HOW to take a Mickey Mouse limited range cap tester and extend its highest capacity range coverage.

Insert a 10 ohm resistor . . .no power level is involved . . . in series with your + meter lead and track down SEVERAL electrolytics in the 220-470-680-1000-2200-3300-4700 ufd values in different equipment and measure and take note of the reading produced by each one..

Make yourself a correction chart, to compare the meters capacitance readout to the ACTUAL value of capacitor being tested.

Now, when you encounter a capacitor greater than 200 ufd, you can use the series resistor to take a capacitance reading and compare to the correction chart to estimate the value of the > 200 ufd cap., I
think that I remember that this will work on up t0 4700 ufd or so, but on above that capacitance may be
totally stretching it a bit.

PHOTO MARKUPS:

Yh0kJzO.jpg


http://i.imgur.com/Yh0kJzO.jpg


73’s De Edd
 
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1-The output caps is new so they are working
2- i test the main raw dc storage cap after disconnect it of the board and it's working
3- i test the lv schootkey recetifier after disconnect it of the board and it's working

4- the 8 legs ic is LTA803n

hope you can help me diagnosis the error

I test the ac and dc on the board not the wire
 
i measure the dc vote on the main raw dc storage cap and it was 330 v
also over the switch-mode power devices ..BP or FET it was 330 v dc


i tried to measure the DC volt between the red circuit and i get shorted in the blue area as shown




and this is after cleaning



the should i replace the blow up R100 with 100 ohm resistor?
 
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You have two power FETs there I can't read for sure, if both are K3568's or K3569's or a K3568 and a K3569 . . . . I am certainly thinking that I am seeing one of both.
Your good R100 should be a 10 ohm, check it out.

73’s De Edd
 
You have two power FETs there I can't read for sure, if both are K3568's or K3569's or a K3568 and a K3569
it's K3568 and a K3569

but still what is the cause there's no dc volt at the output if every thing is working i also gave you the measurements on the big capacitor
 
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