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What technique did you use, the "anchor a corner, flood the pins with solder, clean it up with a braid" approach, or something more sophisticated?

Ugh, 0.5mm lead pitch. That's intimidating. It's kind of a cool device given it can be *either* 8bit x 2Meg or 16 bit x 1Meg.   Here's an outfit that can order it straight from Digi-key and bond it to a DIP-48 adapter board for you! Of course that makes the price of each chip $26. Ouch.

It's the motherboard from a Tandy 1000 HX. Those and their sister machine the 1000 EX are really oddball PC compatibles that are packaged in "computer in a keyboard" format that looks kind of like a gigantic cross between a Color Computer III and an Apple IIc. The motivation to start building...

... per that last picture and what I said about caps with their leads "pre-splayed": if you look at the top card in that stack you can see how the disks in the row next to the vertically oriented chips are sitting kind of awkwardly sidewise? Those are a slightly different value of cap buffering...

If you google it there's a claim that some particular 2001 iBooks came with some kind of stinky adhesive on a label stuck on the back of the keyboard. It seems like they all trace back to a few people griping on the Apple discussion forums and an article in Low End Mac, and in every case it...

FWIW, at least everything on it other than the EMS mapper (and the replacement of other decoding logic with GALs) has already been tested before. Here's a picture of my first prototypes running. (The three PCBs piggybacked on top of the Tandy motherboard.)  

There's videos of people hand-soldering TSOP-II (and even smaller) with a plain old iron and some desoldering braid, so it's apparently *possible*, but, yeah, eek, .8mm pitch is kind of scary.  There's another project I have in the planning stage that requires a 100 pin quad package with .65mm...

I am curious what he's doing. If I had to take a wild guess based on the odd chunky dithering of the texture maps... I dunno, I wonder if he's doing something with the blitter that effectively amounts to rendering the scene at effectively a much lower resolution and using the blitter to "splat"...

If you want to talk agonizing routing jobs here's that project I've been working on. I just finished the bulk of the routing a couple days ago, I'm basically sitting on it for a few days before sending it off to make sure I'm done having "OMG, I totally forgot about... !!!!" moments or other...

Why? You have a VCC connection to each pin, you literally just have to drop the capacitor right next to the chip, run a short trace to the VCC pin, and connect ground to the ground pour. Edit: Judging from the render of your board It looks like you're using Kicad to lay this out? That's what I...

Oh, yeah, good catch. You should be fine with a 10-100nf (I use .1 picofarad by default, which is a 100nf) placed near the VCC input on each chip between VCC and ground. These are important; on one of the vintage computer forums someone was complaining about getting really unreliable...

That must be one rare bird, given Digikey doesn't even list it as an obsolete part (they're pretty good about telling you "yeah, this existed but we don't have it). And I can't find anyone, not even on Aliexpress, claiming to have it for sale. Not to get conspiracy-theory-y but I wouldn't rule...

Here's a video about previous DOOM clones for the Amiga. Note that it doesn't really make a clear distinction between games that run okay on the original 68000s verses needing later Amigas. The short version is that Amigas *do* have substantial video acceleration capabilities compared to...

Ha! I'd hardly call what I do "engineering". I just decided last year it was time to get off my butt and actually make some stuff myself instead of just shouting from the bleachers, everything I "know" is stuff I picked up in the process. The thing I'm working on involving '670s is an EMS RAM...

... Maybe I also have a bit of a vendetta for the '154 because the original .6" wide DIP package of it is genuinely obsolete and costs an arm and a leg now. (It's common in old 8 bit computers and I bought one at one point because I suspected the one in my Commodore PET might be bad. Turned out...

"Obsolete" is a tricky word when it comes to 74 series logic. It's rare for a part to actually stop being manufactured *completely*, but there are parts like the '154 that for whatever reason just don't end up being popular enough to get ported to new processes. That's what I meant. It's...

Is it solely the availability of a ‘154 in HC that’s driving the urge to mix processes? I was serious earlier when I said the ‘154 was considered an obsolete part and had been largely phased out. ‘138s and ‘244s are readily available in any process and if DIP is preferable to you over surface...

I second the suggestion of adding more solder. Don’t be afraid to pile it on, just make sure it actually transfers enough heat to what’s there that the whole mess melts. The additional thermal inertia and area will give the solder sucker a better chance.

As I mentioned, HC is slightly more efficient than HCT if you're interfacing solely with CMOS family parts. HCT should work but there's no reason to prefer it over HC. Is there some part you want that doesn't come in HC? Edit: I guess for the record if the parts in the laptop are AC then...

HCT is CMOS process logic (so it uses less power than LS) but it essentially has built-in pull-ups so it can be mixed freely with TTL logic. I've mixed LS and HCT in the boards I built for my Tandy 1000s freely and it works fine. HC, yeah, you have the "pull up" issue. Here's a PDF talking...