Monday 29 August 2011

to be continue

untuk selanjut'y...akan di terus kan...masih terlalu sibuk belum sempet nulis

Saturday 20 August 2011

repair Lcd dell 15" model 151fpb -display white colour


pertama2 test lcd tersebut hubungkan dengan pc lalu masukan tegangan ac.dan swetelah itu ternyata pada tampilan lcd tersebut berwarna putih alias white colour.apakah gerangan rusak lcd tersebut..?


saya buka cover lcd tersebut.setelah itu saya amati dan cermati apakah ada gejala2 lain pada lcd tersebut.??ya ternyata memang ada yaitu pada bagian capasitornya melembung/bengkak.

pada bagian capasitor yang bengkak/melembung tersebut nilai ialah 470uf/35v.terus saya tukar capasitor tersebut dengan nilai yang sama.dan capasitor yang baru pula.

setelah itu saya tutup balik cover lcd tersebut tanpa mengetest terlebih dahulu,apakah kerusakannya memeng benar di situ atau tidak,tapi menurut saya ,saya sudah yakin bahwa capasitor tersebutlah yang rusak.

setelah itu kemudian saya test lcd tersebut dihubungkan dengan pc.dan wah hasil..mak biyak(dalam bahasa jawa)...display tersebut kembali normal dan tidak berwarna putih lagi...dan dalam batinpun saya berkata:"Wah tinggal tunggu bayaran nie.."alhamdullilah..

yah..ini merupakan secuil pengalaman kecil bagi saya sendiri...mungkin masih banyak lagi diluar sana teknisi-teknisi yang lebih ampuh/mumpuni dari sari saya..akhir kata wassallam

how To Repair Dell E151Fpb LCD Monitor Repair- No Display Problem



Dell E151fpb LCD monitor came in with the complaint of no power but upon carefully look at the LCD you could see a very light (blur) white flashes across the screen and the power LED is not lit. Removing the cover was a bit easy compared to other models.

As usual whenever the mainboard and power board were exposed, I would look for any bulged capacitor, darkened area, a loosen connector and etc. However this monitor boards looks perfectly okay. The next step was to separate the power/inverter board with the main board.

Power was applied to the power board and I could hear a soft ‘chip-chip’ sound. When I measure the 12 volts line with a digital multimeter, the readout was about 7- 8 volts which was very unusual. In fact this is good news to us because we know what the next step that we should make.


Now we could use a 12 volt automobile brake light bulb to test at which section that is causing the low voltage output problem. If the LCD monitor designed to run on 18 or 24 volts then you could use a light bulb from the big trailer. A defective component in either primary or secondary side could cause low output voltage. Removing the fuse as shown in the photo and connect the bulb between the supply line and the cold ground could tell which section is giving problem. You could use this method but first you must confirm that the secondary filter capacitors, TL431 adjustable precision shunt regulator ic, optoisolators and components surrounding the optoisolator is working before you proceed to use the light bulb.



When the power is on the light bulb still do not lit and the sound still could be heard. This indicates that the primary side is having problem and we can leave the inverter/high voltage area and fully concentrate to locate the faults in the primary section.

This is the time to really test your basic electronics skill because you now know at which area the fault is and you just have to use your skills to locate the exact bad component. There were not much components in the primary side, and you could easily check all of them in less than 20 minutes. After checking all the components I was surprised that all of them tested okay. Primary winding of switch mode power transformer rings 8 bars which indicates good and even the uc3842b PWM power IC replaced the power still won’t work! It was quite challenging to troubleshoot this kind of problem where you are hundred percent sure that the primary side is giving problem yet you could not find out the culprit.

Since I had checked all the components and could not locate the fault, the only way that I could do is to direct replace the semiconductor devices such as the diodes, scr, fet, and transistors. From experienced I do encountered semiconductor components breakdown when under full operating voltage.

One by one of the semiconductor components I replaced and power on each time I had changed it to see if the bulb light up or not. Guess what, you would not believe what have I just discovered-a defective 2N7000 fet! The moments I have replaced this fet and power on, the bulb immediately light up. I could not believe it was this faulty fet that causes all the output voltages to drop! I was so happy that I eventually solved the problem and who knows this could be a common fault for all DELL E151Fpb LCD monitor- so please take note to all LCD monitor repairer.



I began to check again the defective 2N7000 fet with my analog meter and peak electronic atlas component analyzer and the result is still the same-tested good! Just like flyback transformer, the best testing equipment to test Fet and other components is actually the equipment itself because it runs on full operating voltage, frequency, signal and etc. What you have just learned from here was that if all the suspected components tested good, the only way to reveal the truth is to direct replace the parts. Hope you enjoy this article and more good articles to come everyday! Wishing you all the best and happy repairing!
by:electronic repair guide.com

lirik lagu ngamen 2 (asolole icik-icik ahum)

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Mak iki anakmu prawan

wiwit mbiyen ono ing perantauan

iling ngiwangi neng kantin sekolahan

telong sasi mak aku urung bayaran

mak dongamu mandhi tenan di bring jabani marang gusti pengeran

koyok ngene rasane wong ora duwe

duwe pisan di ece karo kancane

iling-iling manungso bakale mati

yen wes mati di kubur sanak family

di pendem jero di apit bumi

ono kubur iku akeh pandoso

ulo klabang kolojengking podo moro

ono setan membo-membo dadi perawan

benno krasan yen ono kuburan

neng akhirat ora ono montor liwat

neng akhirat ora ono sego berkat

neng akhirat ora ono mejo biliard

onone godo ne moloikat

(Asolole...icik-icik ahum)

sak sugeh, sugih e uwong mesti ono mlarate

sak mlarat, mlarat e uwong mesti ono celenganne

mangkane golek bojo ojo mandeng rupo

rupo elek kuwi yow ora dadi ngopo

mangkane golek bojo ojo mandeng bondo

seng pentingg, ora ngenteni warisan moro tuwo

kowe pancen keren le, koyok bekas pacarku mbiyen,

eman, eman tenan, kerenmu mung kanggo obralan

obral, obral janji le urung mesti uripmu mulyo

mulo aku wes kondo, melu aku urip nang deso

ngiwangi gawe boto, menek kelopo nyeblok bongko

(Asolole..icik-icik ahum)