DogTag
Offline
Murcia, Spain

Hello everyone.
I've spent half of my day trying to backlight a DMG for my first time.
It's been a mess. I couldn't take out the two layers behind the LCD and had to manually scratch all the polarizer with a knife, making some ugly scratches on the screen.
But the problem here is once I finished everything some horizontal lines (all in the same place and one next to the other) have appeared on the upper half of the screen.
I've tried applying pressure to the contacts of the side ribbon cable but doesn't seem to work at all.
I also checked the plastic bus conecting to the side of the screen and looks just fine.
I used rubbing alcohol to clean the screen, is it possible that it did something on the circuitry there?

I hope there's a solution. This is my first proudly backlighted DMG, but with the inconvenience of those damn lines...

Thank you guys in advance.

SketchMan3
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NC in the US of America

It's next to impossible to get rid of horizontal lines.

Majus
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I also built in my backlight just yesterday and got horizontal lines from it.
I also had to scratch the polarizer and yeah, I also used alcoholic stuff to clean the glass. Besides this freaky coincidence of you and messing around with polarizer the same way on the same day, I have to admit, it might be caused by the brute force I had to use.

In my case the missing lines reappaer by pressing said ribbon cable, but suddenly my screen just went totally black, so I wouldn't recommend doing so.

DogTag
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Murcia, Spain

I'm sorry to hear the same thing just happened to you. I'm resisting to believe that I have ruined the screen forever... Maybe someone's got an idea or recommendation for us.

Timbob
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http://blog.gg8.se/wordpress/2011/07/21 … er-to-fix/

here's some more info about why some lines are harder to fix..

Telerophon
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Austin, Texas

Finesse when you peel the polarizing film is the only answer unfortunately, guys. sad

Rubbing alcohol is fine and wouldn't have damaged the ribbon cable, it probably mechanically separated when you were removing the rear polarizing film.

rygD
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DogTag wrote:

Maybe someone's got an idea or recommendation for us.

if you are feeling lucky you can heat up that side of the LCD, but I wouldn't suggest it.  I have had limited success with this (
reducing the number of horizontal lines on screens that had a handful) but I think it is riskier than it is worth.  I think you are more likely to make it worse.

Telerophon
Offline
Austin, Texas

The best chance you've got is something like a hairdryer or a heat gun on the lowest setting, but that's a long shot and might not work.

thnikk
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Your best bet is to just buy a dmg on ebay that won't turn on and take the front pcb out.

DogTag
Offline
Murcia, Spain

Yeah, I might just get another one... I wanted to make a cool DMG for chiptune, with clear case, green frontlight, custom buttons, pro sound mod etc, so I might try that again on another one.

@rygD Anyway, how does the hair dryer thing work? I mean what do you have to do exactly on the side of the screen with it? Why is it risky?

Last edited by DogTag (Oct 7, 2012 9:33 am)

Telerophon
Offline
Austin, Texas

If you're concerned at all that you're going to damage more front boards, you might be better off buying or commissioning a pre-backlit front board in the Trading Post.

I know Apeshit and a few other dudes have done them on request before, and I'm going to sell one of mine in the near future, so they pop up from time to time.

Not to plug my own upcoming sale, just saying that I know from experience that people sell pre-lit front boards. wink

Majus
Offline

I guess i'm ok with those few lines. I also thought of buying a new one and try my best on the next backlight, this time i'll be a lot more careful hmm

DogTag
Offline
Murcia, Spain

Same thing here Majus, though I'm not ok with a few lines, I want none xD
@Telerophon I'll check that, though I'll have to see prices...

DogTag
Offline
Murcia, Spain

@Telerophon Are you finaly going to sell any pre backlit board or front board? I'm asking for them in this thread:
http://chipmusic.org/forums/topic/8701/front-dmg-pcbs/
Thank you!