Yes, I know this is the wrong site to be asking this. Also, I don't really know where to look for solutions to this sort of problem, so here I am anyway. My problem is I have an old laptop that doesn't power on. It's a NEC Ultralite, model PC-410-1511. As with most antique tech issues, it's been impossible for me to find anything like schematics or repair guides for the machine. I guess I'm mostly just looking for advice about where I could go on my journey next to find proper information about the machine so I can eventually fix it and play commander keen the same way I did as a kid. Thanks~
you'll probably have better chance at finding a semi-usable model of that, (so that you can mix n' match) the components than getting the schematics. this is assuming that you are sure it is not the power adaptor that's the issue. googling shows that laptop is from previous century, is that correct?
Correct. I've also checked the power supply and confirmed the proper DC output, so it's not that unfortunately...
you could test the dc-in jack (including its assembly and the wires) first, to make sure the current flows through properly from end-to-end. that shoud not be too hard. in any case, for such laptop, it is a good idea to have a donor set (or two) in hand. even if you can send in for a specialist repair, the cost probably won't worth it. you don't know yet if the screen is still working, or its dc-ac inverter is. that could be a potential roadblock down the road. getting a similarly aged (laptop) but in working condition might be a cheaper alternative, that is you really, really, really wanted that generation of laptops.
Can't really get a donor on it since no one is currently selling that model anywhere... I might just shelf it and take some more electrical engineering classes later so I know more about how to go about fixing it next time I want to take a crack at it. It's mostly just a nostalgia thing for my brothers and I since we all practically grew up on this thing.
if you're willing to shell out the cost, it can definitely be fixed now. as long as you told the repairman you're willing to pay the same as a more modern laptop (which is also might be cheaper than a repair cost will be). they might also ask you to pay upfront, to avoid them doing the work for nothing. if it were in my city, the cost should not be more than 50 usd. 50-80 is the standard repair cost here (emphasis on 'repair', not replace)
Board diagrams are really hard to find for most laptops because the manufacturers don't release diagrams to the public. Most diagrams that exist are created by third-parties and sold as part of professional repair software. Even then, usually only the most popular laptops get the third-party diagram treatment because it takes an eternity to document every SMD, chip, trace, and component on a motherboard. I'm willing to bet that the only place you'd be able to find a board diagram for your laptop is on a really old tape backup of all the documents related to the laptop somewhere at at NEC. That said, it's easy to identify and test most of the SMDs on the motherboard for faults. Replacing most SMDs doesn't usually even require a donor board. As long as you know how to correctly identify SMDs, you can usually find replacements for just a few bucks online. Best of luck. EDIT: If you have experience with soldering, you could even try reballing or reflowing all the BGA chips on the board. Start with reflowing. If that doesn't fix things, I'd generally only reball any chips near other components that are faulting with multimeter testing. It requires a lot of time to reball a chip, and if you don't wish for the death all life on Earth, there's a good chance you'll develop that sentiment after you've reballed a chip or two.