Re: Dell E172fpb

Hi !
After months fighting with that stupid dell monitor i still have the same pb: it works fine 5 mins and swithces off !
I ve noticed that both Q759 and Q760 get very hot: much hotter than their counterparts. Someone knows what the reason could be ? and what to do ?

Re: Dell E172fpb

Hello !

I posted a couple of question last year about this pb with the Dell/Benq inverter and there is one more to come:

I replaced the transistors with some BD911 whose Hfe is between 40and 250 at 0.5A. But the original SC5707 have a value between 200 and 560.
Is that a Pb ?
It seems the 3055 has an HfE situated between 20 and 100...
The sc5707 are more expensive too ...


Now I am a total noob in Electronics, but couldnt that be a reason why these get sooo hot ?
My BD 911 get really...

Re: Dell E172fpb

Hi !

Thanks for your tip !
[B]
So you think it is just due to poor soldering ?[/B]
My trans are mounted externally: no heat there...

I will try to find something inside when i get the timeRe: Dell E172fpb

Hi !

Thanks for your tip !
[B]
So you think it is just due to poor soldering ?[/B]
My trans are mounted externally: no heat there...

I will try to find something inside when i get the timeRe: Dell E172fpb

Hi !

Thanks

Re: Dell E172fpb

Hi !
Thanks for answering...

This is strange...

The firts time the screen switched off was after 5 hours running.
The second after 2 hours
Then 1 hour and lately 15 mins...


I'm a bit reluctant to open it all again i have to say...

But i think you are right: i will try that when i have time...

Thanks

Re: Dell E172fpb

Hello

I ve had the same problem as many with an E172fpb BenQ and the infamous flashing led after 1 sec.

I had to change two transistors out of the group of four located near the plugs for ccfl.

I used two BD911 from SGS mounted externally on radiators (heat !!!) and everything worked fin ... until yesterday (that 's 6 days after the repair)

When screen is in use, np. But after 2 hours or so, the top ccfl goes dimm for 2 sec or so and screen turns off completely. If i let it cool down, it restarts and is...