Greetings from the United States of America, everyone!
I recently bought a Compaq Portable III computer off of eBay, and it would be the best computer I've ever bought since my Apple II...
...if it weren't for a few problems my screen has. The screen itself is an orange gas-plasma screen, which I think is susceptible to severe burn in. However, it hasn't happened to mine, which is VERY good.
The problems I'm having are:
1. When I turned on the machine for the first time the screen had 3 black lines running from top to bottom.
I thought that the problem was caused by bad ZEBRA contacts (the rubbery/flexible sandwiched contacts found in LCD displays), so I opened the screen module to see if I could fix the problem, but apparently gas-plasma displays don't have ZEBRA contacts. (I had experience trying to get rid of dark lines from a Zenith Supersport laptop because the ZEBRA contacts would not press together properly.) Then I tried pressing on the rubber strip that presses the cable contacts against the screen contacts. No change. Then I realized something that I thought was a fluke: DOS text would poke through the dark spots when the contrast was turned up high enough.
Someone on another vintage computer forum suggested a poor solder joint. (To me, that means that a few pins of a few of the driver chips on the cable had disconnected.)
I decided to ignore the problem for now until I could get a precision soldering iron with a point small enough to reflow the solder on the chip pins. I was about to try transferring a copy of Arachne web browser for DOS today, until THIS happened:
2. I heard a *PTTfsssssHHHHHHH* sound and magic smoke came from the vents of the screen module. However, to my surprise, the screen did NOT FAIL! I shut it off anyways just in case.
When I reopened it, I tried looking for obvious signs of board component failure on the video driver board, but I couldn't really find any... Until I noticed a nice spray on the back wall of the module I had not seen the night before, which matched up with the location of a cap on the board, with a neat little hole in the plastic covering of the cap. I'm not exactly sure what kind of cap to get, since all I know about it is it's a 250v 1uF axial capacitor. I don't know the other specs, so I can't make a determination yet.
I wanna be able to fix this thing so I can play The Secret of Monkey Island! TT.TT