An expansion board with two 8-bit ISA slots plugged into a Sharp laptop

New Expansion Module Brings Standard Slots To Ancient Laptop

April 4, 2023 by Robin Kearey 10 Comments

Upgrading and repairing vintage laptops is often a challenge — even if their basic hardware is compatible with ordinary PCs, they often use nonstandard components and connectors due to space constraints. The Sharp PC-4600 series from the late 1980s is a case in point: although it comes with standard serial and parallel ports, the only other external interface is a mysterious connector labelled EXPBUS on the back of the case. [Steven George] has been diving into the details of this port and managed to design a module to turn it into a pair of standard ISA ports.

Apparently, no peripherals were ever released for the EXPBUS port, so reverse-engineering an existing module was out of the question. [Steven] did stumble upon a service manual for the PC-4600 however, and as it turned out, the connector carried all the signals present in an 8-bit ISA bus. Turning it into something useful was simply a matter of designing an adapter board with the EXPBUS connector on one side and regular ISA slots on the other.

The board also has an external power connector, to avoid overloading the laptop’s internal power supply, as well as a couple of buffer capacitors to smooth out the power rails. [Steven] tested the expansion board with a network adapter and a sound card, and it appears to be functioning well. It should be noted that only the +5 V power rail is available by default, so if any cards need +12 V or any negative rail, those should be provided externally.

Gerber files for this project are available on [Steven]’s website, so if you’ve got one of these machines lying around, now might be the time to upgrade it. This isn’t the first expansion for the PC-4600 series that [Steven] developed, either: he also designed an external floppy drive adapter that should ease data transfer with other PCs.

It’s great to see how the hacker community keeps classic portables like this one alive: one day it might also need a broken screen replaced or a dodgy power supply repaired.

TRS-80 Model 100 Inspires Cool Cyberdeck Build, 40 Years Down The Line

March 4, 2023 by Dan Maloney 19 Comments

The TRS-80 Model 100 was a strange beast. When it debuted in 1983, it resembled nothing that was available at the time, and filled a gap between desktop computers and the mostly-not-invented-yet laptop segment of the market. Collectors covet these machines, but they’re getting harder to find four decades later. So, if you want one, you just might have to roll your own.

Honestly, it doesn’t appear [Roberto Alsina]’s purpose here we to recreate the Model 100 per se, but rather to take inspiration from its oddball form factor and experiment with the latest components. The design elements from the original that [Roberto]’s creation most strongly echo are the screen with the extreme landscape aspect ratio and the somewhat compressed keyboard. The latter is based on the cheapest mechanical 65% keyboard available, while the former is a 1920×480 LCD display intended for automotive applications. The display seems like it put up a fight, between its need for a custom HDMI cable to connect it to the Radxa Zero SBC under the hood as well as the custom kernel needed to support it.

Along with a USB hub for IO and some 18650s for power, everything went into a 3D printed case with considerably sleeker lines than the Model 100. It’s worth pointing out that [Roberto] didn’t have much experience with design or 3D printing when he kicked off this project. We love to see people stretching their skills like that, and we think the results are great in this case. We’ve seen a lot of Model 100 retrofits and brain transplants, but this may be the first time we’ve seen a build quite like this.

Two people lounge over a wooden tabletop to lean on a large black laptop. It has a green leaf on its 43" LCD desktop and RGB lighting around its edge is glowing a slightly deeper shade of green.

Supersized Laptop Laughs In The Face Of Portability

February 23, 2023 by Navarre Bartz 18 Comments

Sometimes a project needs to go big, and [Evan and Katelyn] threw portability to the wind to build the “world’s biggest” laptop.

Stretching the believability of “bigger is better,” this laptop features a 43″ screen, an enormous un-ergonomic keyboard, and a trackpad that might be bigger than your hand. Not to be outdone by other gaming laptops, it also features RGB lighting and a logo that really pops with neon resin.

The pair started the build with an aluminum extrusion frame joined by hinges. Plywood forms the top lid and bottom of the device, and the interior was covered with a mix of vinyl and ABS to keep everything tidy. A nice detail is the windows cut in the area above the keyboard to keep an eye on the charge of the two battery packs powering the laptop. Weighing more than 100 pounds, we suspect that this won’t be the next revolution in computing.

If you need more supersized gadgets, maybe try out the world’s biggest working keyboard or this giant Xbox Series X?

Antenna Mount Designed For On-The-Go SDR

December 16, 2022 by Bryan Cockfield 15 Comments

Software-defined radio is all the rage these days, and for good reason. It eliminates or drastically reduces the amount of otherwise pricey equipment needed to transmit or even just receive, and can pack many more features than most affordable radio setups otherwise would have. It also makes it possible to go mobile much more easily. [Rostislav Persion] uses a laptop for on-the-go SDR activities, and designed this 3D printed antenna mount to make his radio adventures much easier.

The antenna mount is a small 3D printed enclosure for his NESDR Smart Dongle with a wide base to attach to the back of his laptop lid with Velcro so it can easily be removed or attached. This allows him to run a single USB cable to the dongle and have it oriented properly for maximum antenna effectiveness without something cumbersome like a dedicated antenna stand. [Rostislav] even modeled the entire assembly so that he could run a stress analysis on it, and from that data ended up filling it with epoxy to ensure maximum lifespan with minimal wear on the components.

We definitely appreciate the simple and clean build which allows easy access to HF and higher frequencies while mobile, especially since the 3D modeling takes it a step beyond simply printing a 3D accessory and hoping for the best. There’s even an improved version on his site here. To go even one step further, though, we’ve seen the antennas themselves get designed and then 3D printed directly.

An Open Source PowerPC Notebook Edges Closer

December 9, 2022 by Jenny List 21 Comments

Back in 2020, we reported on the effort to create a brand new open-source laptop platform using the PowerPC architecture. At the time they had big plans and a PCB design, and we’re very pleased to report that in the intervening two years they’ve progressed to the point of now having some real prototypes ready for testing.

Some might question why this should be necessary, after all there are plenty of laptops and more than one commonly available processor platform. But that’s to miss the point of open source hardware, that it’s as much about plurality as functionality. But if you’ve only encountered the PowerPC architecture in slightly older Macs and some game consoles, what’s the chip powering this device? The answer is, not one of those venerable chips, but the NXP T2080, a 1.8 GHz quad-core device that boasts a respectable power for a laptop.

There is of course many a hurdle still to be crossed between prototype and final device, but given the challenge of a functioning laptop it’s impressive for them to have reached this milestone at all. We look forward to seeing further iterations, and maybe, just maybe, a finished device one day. Our original coverage is here.

The bottom half of a MacBook Air on a purple and pink background has severed wires drawn out of its back to indicate its lack of a screen.

Are Slabtops The Future Of Computing?

November 25, 2022 by Navarre Bartz 114 Comments

The most popular computer ever was the Commodore 64 with its computer-in-a-keyboard form factor. If you have a longing for a keyboard computer with more modern internals, one of the easiest solutions today is to pull the screen off a laptop.

[Umar Shakir] wanted to see what the fuss was about regarding a recent Apple patent and took the top lid off of his M1 Macbook Air and turned it into a “slabtop.” The computer works great wired to a monitor but can also be used wirelessly via AirPlay. The approach doesn’t come without its downsides, of course. Newer MacBooks can’t access recovery mode without the built-in screen, and some older models had their WiFi antennas in the top lid, so making one into a slabtop will leave you desk-bound.

While [Shakir] focuses on MacBooks, this approach should work with any laptop. Apparently, it’s a cottage industry in China already. Back in the day, my own daily driver was a Pentium-powered laptop with its broken LCD (and lid) removed. It worked great with whatever CRT was nearby.

If you’re looking for an off-the-shelf keyboard computer of your own, you might want to check out the Raspberry Pi 400.

Laptoppin’ Like 1975

August 6, 2022 by Al Williams 22 Comments

When we first saw the PZ1 laptop — a 6502 laptop-style computer with a small display and 512K of RAM — we couldn’t help but think of the old AIM 65 computer from Rockwell, although that only had 1K of memory. The other thing the AIM didn’t have was an ancillary microcontroller to help out that is way more powerful than the main processor.

There are actually several versions of the PZ1 and you can find some very detailed information over on Hackaday.io and GitHub. Recently, [Adam] release version 2.0 and tested some PC boards that are working well.

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