Thread

Screen longevity

68kMLA Troubleshooting 15 posts Nov 22, 2009 to Mar 5, 2010

#1 Sun, 22 Nov 2009 - 23:00 68kMLA

Having several modern CCFL backlit LCDs that have gone dim, I'm wondering how well the 68k portables' LCDs hold up to age. What are some of the common problems, and what should one look for when shopping for a 68k portable these days?

#2 Mon, 23 Nov 2009 - 06:44 68kMLA

The only issue I have run into is on an old Powerbook 170. It suffered from black corners of the LCD when on for a long period of time.

All my other powerbooks work fine. Mind you the dual scan screen on the duo 230 is terrible.

#3 Mon, 23 Nov 2009 - 13:19 68kMLA

I had the tunnel vision/darkening corners fault on a Duo 280 greyscale. i think that's a fault in the LCD itself rather than the backlight, but I am open to better information.

#4 Mon, 23 Nov 2009 - 14:50 68kMLA

In my experience, passive matrix screens can have leaked caps, causing screen issues such as a faint display/occasional "yellow-out" issues. I had it happen to a PowerBook 140 and a PowerBook 160.

#5 Sat, 28 Nov 2009 - 21:53 68kMLA

My PowerBook 180 has a single dead pixel.

#6 Sat, 28 Nov 2009 - 22:22 68kMLA

In my experience, passive matrix screens can have leaked caps, causing screen issues such as a faint display/occasional "yellow-out" issues. I had it happen to a PowerBook 140 and a PowerBook 160.

Where are the guilty, leaking caps?

#7 Sat, 28 Nov 2009 - 22:59 68kMLA

Supposedly in the LCD display.

#8 Sun, 29 Nov 2009 - 01:30 68kMLA

Supposedly in the LCD display.

Pics?

#9 Sun, 29 Nov 2009 - 03:26 68kMLA

It's an interesting suggestion. My PB160 has a fairly poor greyscale display (which improves dramatically when set to display Black & White only), and I had a 145b that I had to junk because the display was so bad. The logic boards look pristine.

It would be relatively easy to take the lcd apart and have a peek - even washing might do the trick, or else minimally help with diagnostics.

Mind you, I recently got a PB180 on here with no display problems at all, and that seems to have cured my PB1xx series wanderlusts for the present. The PB160 and its screen will have to wait.

#10 Thu, 18 Feb 2010 - 04:31 68kMLA

With enough patience, precision, and critical thinking, you can replace the lamp(s) in most LCDs. I have replaced lamps in two PowerBook G3 Pismo screens. One was dim, the other had turned pink in the corner, and it was spreading.

I'd imagine very very old LCDs couldn't be any harder. I sourced my lamps at Digikey with some help found googling. They have a huge selection. If you screen is dim or tunneling, remember this as a possible option if you trust your fine motor skills.

#11 Thu, 18 Feb 2010 - 05:48 68kMLA

I have a PowerBook 1400cs and a Powerbook G3 Lombard, but I bought it from a site with the same idea as eBay, so I don't know if it is intended to be brighter.

#12 Thu, 18 Feb 2010 - 15:58 68kMLA

I'd imagine very very old LCDs couldn't be any harder.

It is stupidly easy in the displays in the 1xx series.Like, mars478 could do it.. though he might break the lamp later.. but meh.

hehe

#13 Fri, 5 Mar 2010 - 00:57 68kMLA

I have two 150's here that have entire sections of the screens dead. They partially work, but those dead areas make it impossible to really use them.

#14 Fri, 5 Mar 2010 - 01:36 68kMLA

I have a ton of old Thinkpads with great screens from the mid 1990's, yet a few newer with some pink or dead bulbs. If I had to guess I think the older smaller screens had bulbs that just last longer then the higher output bigger screens.

#15 Fri, 5 Mar 2010 - 02:00 68kMLA

I have two 150's here that have entire sections of the screens dead. They partially work, but those dead areas make it impossible to really use them.

I have a 190 like that. On mine, there is a bad connection between the printed ribbon cable and the actual LCD. I found this by touching and wiggling various parts. A possible solution is to wedge something in there that keeps pressure on the affected area.