Hannspree HF257 2-3 seconds black

[Hippie459MN]

Re: Hannspree HF257 2-3 seconds black

Mine pretty much did the same thing and after chasing parts and replacing things, I finally gave in and busted open the LCD an turned out to be 2 bad ccfl tubes on the bottom of the monitor. I ordered 4 new ones from lcdparts and put them in myself but I can tell you, its not an easy job and them tubes are tiny! So unless your confident you can change them yourself, you would be better off converting them to LED or buying a new monitor all together cause it would cost more to pay a shop to change them then the cost of a new LED monitor now days.

I am thinking of converting the two HF257s I have over to LED but not sure how hard that would be.

[bluesj]

Re: Hannspree HF257 2-3 seconds black

Hi.. I have a hannspree HF257 monitor
if the brightness is maximum, it has the '2 seconds to black' symptom.
and when i set the brightness to the minumum (zero), it flicker several times with electrical noise like hum and eventually go to black monitor...
but the power led is on and the monitor works with very faint almost black image, and the sound works perfectly


Can you help me?

what should i buy at the following sites?
http://lcdalternatives.com/
http://lcdparts.net/

[Hippie459MN]

Re: Hannspree HF257 2-3 seconds black

Just great! Got the bulbs fixed, put it somewhat back together and when putting it back together the metal frame holding the LCD panel in seemed to be a little tight but I didnt think anything of it and took it and fired it up and it worked beautiful for about an hour with no problems so I decided to put it back in the case and snapped everything back together and the frame seemed a tiny bit tough to snap together but seeing its tough to take apart I just figured that was that and put it on the desk only to now see these wonderful lines in the display. So I would barley push on the sides of the screen and they would kind of flicker so I decided to take it all back apart and there is 3 parts of the LCD that or sticking out the side bend over the edge (only 2 visible here) and well, I must have somehow missed it but the top one in the picture was folded up under the LCD display. All this work and now this... Kind of want to cry. And I dont know that it can be fixed. I was able to kind of wiggle that tab and get some of the lines to flicker and at one point almost had them gone but they came back once I moved anything again.

Me - 0
Monitor - 3

Its bad enough I wont use it cause it drive me nuts. lol The other picture with the mud truck on it is before I put it back in the case and zero lines in the display.

[Hippie459MN]

Re: Hannspree HF257 2-3 seconds black

Well, got it apart and actually was very simple to get them out but as you can see on the bottom 2 bulbs...

Yes, the are both broke on the one end with the wires showing.

I didnt take any pictures of the top 2 but the one has some blacking on both ends but not near this bad and the other one looks fine. I will see how changing out these 2 go and then see how ambitious I feel about doing the other two.

[retiredcaps]

Re: Hannspree HF257 2-3 seconds black

Well, got my replacment lamps today. That was fast considering I ordered them Wed afternoon and Thursday morning they were shipped out and I paid for the cheapest shipping from USPS.

Canada Post is never that fast.

Im not going to attempt it with the chance of my 3 1/2 year old distracting me.

Replacing the ccfls is very very very fragile work. You can't be tired, frustrated or distracted. Wait until the little goes to sleep, then work on it.

[Hippie459MN]

Re: Hannspree HF257 2-3 seconds black

Well, got my replacment lamps today. That was fast considering I ordered them Wed afternoon and Thursday morning they were shipped out and I paid for the cheapest shipping from USPS.

I will tackle this later today or tonight. Depends if this kiddo of mine takes a nap today or not. Im not going to attempt it with the chance of my 3 1/2 year old distracting me. He did good watching me recap the inverter board but thats nothing I havent done before.

I will also try to either get video or plenty of pictures but thinking video will be best so I dont have to stop and take pictures all the time and end of forgetting something.

[retiredcaps]

Re: Hannspree HF257 2-3 seconds black

And the gal at ccflwarehouse was super helpful on the phone too.

Good to hear so we can continue to recommend them.

In case you haven't noticed in my sig file below, there is a guide for troubleshooting 2 seconds to black.

[Hippie459MN]

Re: Hannspree HF257 2-3 seconds black

I know that now. lol I was originally going off what this person said that took a look at the monitor for me when it first started acting up and I didnt have any test lamps at all. I do now though and after doing a lot of reading and working with this, I now now my way around a monitor much better now and will be doing any future testing/repairs myself from the beginning. This has certainly been a great learning experience and even more so once I dig in to getting the lamps out, repaired, and back in.

I cant wait. Sitting here using my spare 15" flatscreen (1024x768 max res) is a nightmare after using my 25" 1080p HD monitor.

[budm]

Re: Hannspree HF257 2-3 seconds black

Using test lamp for verification of the inverter circuits when you have 2 seconds to black is the first thing I use, it saves so much time in troubleshooting.

[Hippie459MN]

Re: Hannspree HF257 2-3 seconds black

Order a complete retube kit from ccflwarehouse for $30 on sale a few days ago. Hopefully I will get them tomorrow (Saturday) and I can get to work on this.

I have never messed with a monitor before and an acquaintance said he had repaired many of them and had a tester for testing caps inline and first told me things were bad and told me to buy this one power supply/inverer board on ebay so I did, coming from china, waited 5 weeks, got it only to have it be bad (Transformer on PS side), so I did a search leading me here and learning A LOT so I decided to recap my original and still having the 2 seconds then black, a friend had an old busted laptop with a good monitor so I grabbed the old CCFL lamps from that and what do ya know, monitor worked great with them hooked up in place of the ones in the monitor so that was the problem. Had I known this, this would have been fixed weeks ago.

And the gal at ccflwarehouse was super helpful on the phone too.

[retiredcaps]

Re: Hannspree HF257 2-3 seconds black

Would anyone have any idea just how long the tubes are so I could order them before I take this apart.

Members have good feedback for ccflwarehouse.com customer service. You can call them and they will help you find the correct size, etc.

They have a tutorial on how to replace as well.

http://www.ccflwarehouse.com/lasotu.html

You can buy lamps "bare" or pre-harnessed. The latter costs more, but is easier to install.

[Hippie459MN]

Re: Hannspree HF257 2-3 seconds black

Well, I have officially figured it the problem and was really hoping this wasnt it but it is. I hooked up a good pair of ccfl tubes to the board and its been on 100% brightness for about a half hour now. Good news it the power supply/inverter board has all brand new FM series caps on it. I can solder really good and change caps and other stuff like that but this taking the display apart has me a bit nervous but im going to give it a go. Dont really have anything to loose.

Try and find some videos on youtube of similar panels

Finding anything about taking a ccfl tube out doesnt seem to warrent to many search results and the ones I do find all seem to be nothing more then a 15" from a laptop and by the looks of it, they are a different animal then a big 25" LCD monitor.

Im going to set up the GoPro and try and get some video taking this apart.

Would anyone have any idea just how long the tubes are so I could order them before I take this apart. I just would rather this not sit around all week in pieces if it doesnt have too. My luck something would get broken or misplaced.

[selldoor]

Re: Hannspree HF257 2-3 seconds black

I will attempt to change out all 4 CCFL tubes. Hope its not that tough. lol

Try and find some videos on youtube of similar panels

[Hippie459MN]

Re: Hannspree HF257 2-3 seconds black

Well, further inspection I can not just slide the CCFL tubes out so I am going to getting some tubes from a friend to hook up and see if if hooking up a good tube works and if so, then I will know if it is a tube of not. Really leaning that way. I did re-cap the entire board and I dont know if the new caps cause this but now I cant turn the brightness up past 11 or it will go out as where before I swapped the caps I could turn it up to about 17 without it going black. I did triple check all of my solder connections and they are all seem to be good.

The bottom portion of my screen does seem dimmer then the top. I will report back hopefully tomorrow when I get the spare CCFL tubes to test the inverter side of the board. If all test good, I will attempt to change out all 4 CCFL tubes. Hope its not that tough. lol

[budm]

Re: Hannspree HF257 2-3 seconds black

I would pull out the lamp assemblies and inspect real close at the wires attached to the end of the lamps, give it a gentle pull if it will just come off or not.
http://s807.photobucket.com/albums/y...klight%20lamp/

Test lamps:
http://s807.photobucket.com/albums/y...g%20old%20CFL/

[Hippie459MN]

Re: Hannspree HF257 2-3 seconds black

Well, after further inspection, looks like changing the CCFL tubes will be a piece of cake if I have too. Looks like I just have to pull the metal frame off enough on one end and they slide right out the side. No need to take it to far apart. I hope....

And it looks like ccflwarehouse.com has a relamp kit on sale for $30 right now.

I do wonder if it isnt a CCFL tube though cause I did have the flickering in the bottom left side of the screen and it was flickering for a good 10 seconds before I shut it off and turned it back on and then did it again for a few seconds and turning the monitor off and back on fixed it again for about 10 min then screen went back and thats when all this started.

I turned out the lights in my office and again fired up the monitor with the brightness turned way down and the lower portion of the screen does seem dimmer and there is an ever so faint flickering to it that I didnt notice when the lights were on in the room.

Just thinking out loud again.

Oh yeah, I did order all the caps from digikey. Plus my cousin works there so I was able to get her big discount on my $7 in parts. Saved like .25 cents. Plus living in MN and digikey being about 3 hours away from me, I dont think it will take long to get them.

Really stuck at a crossroads here with the ccfl tubes. Will report back once I recap it.

[selldoor]

Re: Hannspree HF257 2-3 seconds black

Wouldnt bother recapping with local shop radioshack/ frys caps. They are not usually any good. see if you can get them from badcaps.net or digikey -take care with physical size.
use panasonic fm or fr nichicon or rubycon equivalent caps.

[Hippie459MN]

Re: Hannspree HF257 2-3 seconds black

I think I am going to just re-cap it and see what happens. Time to see if I can track down all the caps locally here.

[selldoor]

Re: Hannspree HF257 2-3 seconds black

S1>S2 = 997 consistent
S3>S4 = between 1004 and 1007

S3>S4 will not fluctuate while being tested but if I test once, wait a min or so, test again it will give a different reading. To me even the 997 sounds kind of high but I could be wrong for those inverter transformers as I do not have any kind of data sheet or any kind of info on them.

They appear to be ok - we usually reckon they should be within 3% of each other - so you are well within that.

I think budm testlamp is the way to go - It is only a test though just try it for a minute or 2
to see if you can spot a weak bulb ( It may just be the wiring)

[Hippie459MN]

Re: Hannspree HF257 2-3 seconds black

Doesn't matter, since he using a stock photo from shopjimmy.

Yes, Sorry about that. I was just using it for a reference as my cheap camera was not getting a good picture at all. I grabbed my mothers camera and got a better picture of my actual board.