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vldmr

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  1. It turned out the 5V power supply for LCD is actually located on the opposite side from LCD flex cable connector - on inverter board, which produces it from 7.5V I believe I mentioned before that my inverter board had couple of burnt capacitors, which I replaced, and was happy with working backlight. I though that indicated that inverter board was fine. Who would have though that this same board also supplies low voltage. Tracing showed the 5V comes out of chip labeled SL90067 of unknown breed - at least I was not able to find relevant datasheet for that. Here is the li
  2. Looks like sutekh moved on to new adventures, so I decided to try to answer my own question myself. I hooked a lab power supply to power rails on LCD assembly, and after powering machine on tried to apply 3.3V at first - nothing changed, no current flow from PS into circuit. After that I took a deep breath and cranked PS to 5V -- aand waddoyouknow: a nice crisp image appeared on LCD, and PS showed 0.1A current drain. So, the supply voltage for LCD on 180C is indeed 5V, and in my case it is at fault, so next I will be looking for a power supply circuits on PCB. Of course, it might b
  3. Interesting - I discussed this repair with a friend of mine, who I trust with anything mechanical, and he also strongly advised on through holes with brass plates on outside. I almost went that route, but then there was a discussion on vcfed forum about fixing hinges, and two members there vouched that epoxy would be good enough, given that the hinge is loosened with fresh lubrication. So I decided there is nothing to loose trying epoxy on internals, and I always can proceed with through screws if that would fail. I just flooded the area on the back panel of the screen around the hinges with e
  4. Interesting story - that I am almost reliving. Yes, I also was looking to get 180c for a long time, and I got one recently for low offer. Mine was in better shape - no leaking battery. Hinge screws ripped out, burned electrolytic caps on inverter (?) board, hard drive with click of death - but the flex cable is in one piece. I glued hinge to screen bacl wall with epoxy, replaced burnt caps, backlight works, but the screen stays blank (white). I tested and confirmed continuity of all traces on flex cable, checked with scope that there are some live waveforms on flex cables leading
  5. I've got a couple of Supermac spectrum/8 series 3 cards to fit into IIci. From my searches it appeared that this card provides QD acceleration, but it turns out to be almost twice as slow as builtin video on IIci. So much for acceleration, but at least it could give 1024x768 resolution. It turned out the video is blurred the same way on both cards connected to LCD monitor at all resolutions and all color settings, even in b/w. Tested on different monitors as well. It appears that timing of color components is shifted a bit so white area gets green fringe on one border and red on th
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