5120 Portable video cable

[jexus]

Hi all, i was fixing a broken internal display cable for 5120... it seems a bit stupid but i cut the cable in two parts to bypass the broken piece but i don't remember if the cable is straight or cross. Checking pics on the web doesn't help. Can i have a detailed pic or the pinout?

thanks

 

[techknight]

Use an old piece of Ultra-ATA IDE cable and replace the entire run. Be careful when separating the crimp fittings, should be able to just re-crimp when you replace the run. And yes, it should be straight. 

Even then it does not matter. there is an arrow marked on the crimp fittings that point to pin 1 of the ribbon cable. When you replace the ribbon, make sure to strip off a section of cable that contains the marked wire. As long as that marked wire is facing the arrow on both ends, it will be fine. 

I have redone 2 5120 cables without issue. 

 

[jexus]

thank you for reply. Before i read this i used an ultra-ata cable but i think i had some problems with the connector that fits on the mobo. I powered up the system and it smelled like something is burning than i suddenly stripped off the power wire. I don't know why but i think something was shorted inside the cable. Anyway is still booting fine from floppy but without the video. I hope i didn't make any damage to the lcd or the video IC.. i'm waiting for brand new connector (the one on the mobo) to build a new cable following your instructions.

 

[techknight]

you probably crimped it slightly off. 

When crimping IDC connectors, you must be dead-on. you cannot skew it in any way, or this happens. 

Depends on how the short occured, and where it bridged. You may or may not have fried the shit out of it. 

 

[jexus]

ok, i made the cable but the result is the same before re-making it (maybe the old one was good).

You can look here: https://s32.postimg.org/gfcy1t6w5/DSC_0514.jpg

Do you think is something related to the contacts between the zebra stripes and the display itself?

I bought the display on ebay and paid a lot of money and now i should open a dispute with paypal.

p.s. the mac is fully working. I guess nothing is fried.

 

[jexus]

p.s. the mac is fully working. I guess nothing is fried.

btw i figured out that short was on the floppy drive.

 

[jexus]

update: opened the display, cleaned contacts nothing changes. Swapped the board with a spare from the old lcd: nothing. What can i do now? The lines remain.

 

[techknight]

thats a bad screen, they will never go away. 

You can try separating the LCD display from its circuit board, and cleaning the rubber zebra stripes, and try again. If that doesnt work, then it will never work. 

 

[jexus]

I tried but nothing changes. Can i say to avoid that seller? Do you think it might be helpful for someone if i tell the ebay nickname? 

Anyway thanks for your help.

 

[techknight]

Its not the sellers fault, chances are he never could test it. He probably tore down a portable into parts because it didnt work, and sold off the parts 1 by 1. This practice is as common as the wind.

When it comes to vintage hardware, its buyer beware. Also its against the rules to call out an ebay username here, Its best to keep that between you and the seller. 

The panel itself is likely bad, it IS an active matrix display, so each pixel has its own transistor array. So if one goes bad or creates a short, you will get that. Unfortunately its game over for that LCD. You will need to find another one

 

[Cory5412]

As mentioned, this is not an off-site seller feedback forum. So it would be better not to post the name of the seller.

Techknight is probably correct: It's likely that the seller had no way to test it, or didn't think that that particular failure was very bad.

Looking at that photo, that LCD may honestly be usable for a while, unless LCDs that fail in that way use a significant amount of electricity, or something. I've used a few laptops with displays that were thusly on their way to death for a few years with no real trouble.

 

[techknight]

Yea, as long as they dont develop more lines it should be ok. But honestly IMHO, I think the storage conditions have a lot to do with that. But again, I cant really prove it. 

 

[jexus]

As mentioned, this is not an off-site seller feedback forum. So it would be better not to post the name of the seller.

yeah but if i tell you the price i paid for this panel you would change your mind... It is not my fault because i asked if he was selling it as untested or working and the answer was "working". He had to declare he wasn't able to test it before selling. Btw shit happens.

 

[jexus]

The panel itself is likely bad, it IS an active matrix display, so each pixel has its own transistor array. So if one goes bad or creates a short, you will get that. Unfortunately its game over for that LCD. You will need to find another one

where are these transistor placed? on the control board? Can it be a zebra stripes contact fault? I cleaned the contacts between the stripes and the panel but didn't remove the frame.

 

[jexus]

ok maybe you're talking about the transistor on the TFT...

 

[techknight]

Yes, the transistors on the TFT itself are likely bad, especially if pressure or flexing does not affect it. 

 

[techknight]

yeah but if i tell you the price i paid for this panel you would change your mind... It is not my fault because i asked if he was selling it as untested or working and the answer was "working". He had to declare he wasn't able to test it before selling. Btw shit happens.

If it was said as working in the Item Description, you can return it on the bounds of Not As Described and get your money back. Thats my recommendation. 

 

[jexus]

yes, this is my normal "modus operandi". In this case the seller offered me a discount, i replied i would have to think about it, keep my damaged screen and have the money partially back or proceed through paypal as item not as described but the seller gave to me 80e with apologies the day after without i said a word.

 

[Bunsen]

yeah but if i tell you the price i paid for this panel you would change your mind...

Trust me, we won't.  This has been a long-standing rule and we're not about to change it or make exceptions.

I'm glad you got some result from the seller.