Presence Sensor Locks Computer When You Step Away

July 2, 2023 by Bryan Cockfield 14 Comments

Having a computer that locks its screen after a few minutes of inactivity is always a good idea from a security standpoint, especially in offices where there is a lot of foot traffic. Even the five- or ten-minute activity timers that are set on most workstations aren’t really perfect solutions. While ideally in these situations we’d all be locking our screens manually when we get up, that doesn’t always happen. The only way to guarantee that this problem is solved is to use something like this automatic workstation locker.

The project is based around the LD2410 presence sensor — a small 24 GHz radar module featuring onboard signal processing which simplifies the detection of objects and motion. [Enzo] paired one of these modules with a Seeed Studio XIAO nRF52840 development board to listen to the radar module and send the screen lock keyboard shortcut to the computer when it detects that the user has walked away from the machine. The only thing that [Enzo] wants to add is a blinking LED to let the user know when the device is about to timeout so that it doesn’t accidentally lock the machine when not needed.

One of the parts of this build that is a little bit glossed over is the fact that plenty of microcontroller platforms can send keystrokes to a computer even if they’re not themselves a USB keyboard. Even the Arduino Uno can do this, so by now this feature is fairly platform-agnostic. Still, you can use this to your advantage if you have the opposite problem from [Enzo] and need your computer to stay logged in no matter what.

An HP9863C partially disassembled on a workbench

Repairing A $25,000 HP Workstation To Run Pac-Man

June 20, 2023 by Robin Kearey 21 Comments

The microcomputer revolution of the 1970s and 1980s turned computers from expensive machines aimed at professionals into consumer products found in the average household. But there always remained a market for professional users, who bought equipment that was so far ahead of consumer gear it seemed to belong in a different decade. While a home computer enthusiast in 1981 might fork out a few hundred dollars for an 8-bit machine with 64 KB of memory, a professional could already buy a 32-bit workstation with 2.8 megabytes of RAM for the price of a brand-new sports car. [Tech Tangents] got his hands on one of those machines, an HP Series 200 9863C from 1981, and managed to get it up and running.

The machine came in more-or-less working condition. The display cable turned out to be dodgy, but since it was just a straight-through sub-D cable it was easily replaced. Similarly, the two 5.25″ floppy drives were standard Tandon TM100-2As which [Tech Tangents] had some experience in repairing, although these specific units merely needed a thorough cleaning to remove forty years’ worth of dust. Continue reading “Repairing A $25,000 HP Workstation To Run Pac-Man“ →

Business On The Outside, Electronics Workstation On The Inside

March 23, 2018 by James Hobson 15 Comments

As an electrical engineering student, [Brandon Rice] had the full suite of electronics tools you’d expect. Cramming them all into a dorm room was doable — but cramped — a labour to square everything away from his desk’s top when he had to work on something else. To make it easier on himself, he built himself a portable electronics workstation inside the dimensions of a briefcase.

Built from scratch, the workstation includes a list of features that should have you salivating by the end. Instead of messing with a bunch of cables, on-board power is supplied by a dismantled 24V, 6A power brick, using a buck converter and ATmega to regulate and display the voltage, with power running directly to 12V and 5V lines of a breadboard in the middle of the workstation. A wealth of components are stored in two dozen 3d printed 1″ capsules setting them in loops pinned to the lid.

If all this was not already enough, there’s more!

Continue reading “Business On The Outside, Electronics Workstation On The Inside” →

3D Printer Enclosure Is Pleasant On The Eyes And Ears

August 2, 2016 by Bryan Cockfield 37 Comments

There’s a lot going on in the 3D printing world. Huge printing beds, unique materials like concrete, and more accessible, inexpensive printers for us regular folk. The only thing that’s often overlooked with these smaller printers is the ruckus that they can make. The sounds of all those motors can get tiresome after a while, which was likely the inspiration for [Fabien]’s home 3D printer workstation. (Google Translate from French)

After acquiring a new printer, [Fabien] needed a place to put it and created his own piece of furniture for it. The stand is made out of spruce and is lined with insulation. He uses a combination of cork, foam, and recycled rubber tile to help with heat, sound, and vibration respectively. Don’t worry, though, he did install a ventilation system for the fumes! After the printer housing is squared away, he place a webcam inside so that the user can monitor the print without disturbing it. Everything, including the current print, is managed with a computer on the top of the cabinet.

Having a good workspace is just as important as having a quality tool, and [Fabien] has certainly accomplished that for his new 3D printer. There have been a lot of good workspace builds over the years, too, including electronics labs in a portable box and this masterpiece workbench. If you’ve ever experienced the frustration of working in an area that wasn’t designed for the task at hand, you’ll easily be able to appreciate any of these custom solutions.

Hanging Monitors Keeps Your Desk Slightly Less Messy

December 27, 2014 by Brian Benchoff 33 Comments

[Gertlex] – like just about everyone reading this, I’m sure – has a messy desk with monitors, keyboards, mice, several other input devices, tablets, and a laptop. He wanted a system that would reduce the wire clutter on his desk and after thinking a bit came up with a really cool solution for arranging his monitors. He’s hanging the monitors from a shelf above his desk using nothing but some aluminum and a few 3D printed brackets.

The main structure is a shelf of ‘bridge’ above his desk, made from 3/4″ ply. The inventive bit of this build is the two 1″ square aluminum tubes spanning the width of this shelf. From these, a few bits of aluminum angle pieces slide along the 1″ rails. a mount holds a 1″ round pipe to these supports, and a VESA mount is clamped to the pipe. There’s an imgur album that goes through the entire design. It’s certainly an improvement over the earlier battlestation, and the wiring loom cleans everything up nice and tidy.

[Gertlex]’s new system of hanging monitors is great, but this simple puts some even cooler builds on the table. The sliding system is great, but by putting one monitor on its own carriage, you could have an infinitely reconfigurable monitor setup. Some proper bearings, 3D printed VESA mounts, and maybe even a few stepper motors would make a build like this the coolest battlestation rig since the great ‘capacitor plague and I have a soldering iron so free monitors’ spectacular of 2005.

Cloning A Board From Pictures On The Internet

November 22, 2014 by Brian Benchoff 15 Comments

[Andrew] was a pretty cool guy in the early 90s with an awesome keyboard synth that did wavetable synthesis, sampling, a sequencer, and an effects processor. This was a strange era for storage; a reasonable amount of Flash memory was unheard of, and floppy disks ruled the land. [Andrew]’s synth, though, had the option to connect SCSI drives. Like all optional add ons for high-end equipment, the current price for the Ensoniq SCSI card is astronomical and [Andrew] figured he could build one of these cards himself.

Poking around eBay, [Andrew] found the card in question – just a few passives, some connectors, a voltage regulator, and an odd chip from AMD. This chip was a 33C93A, a SCSI controller, and a trip down the Chinese vendor rabbit hole netted him one for $7. Can’t do better than that.

With the datasheet for the chip in hand and a few reasonable assumptions on how the circuit worked, [Andrew] tried to figure draw the schematic. After doing that, he found another hobbyist that had attempted the same project a few years earlier. All the nets were identical, and all that was left to do was sending a board off to the fab.

A quick trip to Front Panel Express got [Andrew] a mounting bracket for the card, and after plugging it in to the synth revealed a new option – SCSI. It worked, and with an ancient SCSI CD-ROM drive, he had boatloads of offline storage for his synth. Great work, and something we’d love to see more of.

The Ultimate Workstation That Folds Up

April 13, 2014 by James Hobson 19 Comments

ultimate maker station

Looking for an easy way to keep on making stuff even though you’re living in a tiny dorm room? [Matt Silver] was tired of not having a dedicated work-space, so he spent some serious time designing this modular, re-configurable and collapsible portable workstation ready for almost anything.

He started out by sketching ideas, playing around with 3D models in SketchUp, and eventually building a few prototypes using trial and error — and what he’s come up with is pretty darn impressive. It folds down to just under a foot by three feet squared and has casters to roll it around. Once unfolded, you stabilize it by placing your chair on one of the walls that folds down, and the desk itself is also re-configurable for different work surfaces. He’s included a power bar, an LED work-light, and it even has storage racks for tools on the side.

It’s a very thorough Instructable, and definitely worth a look through — especially to see how it magically unfolds! And if you’re wondering about how much it would cost to build, you’re probably looking at around $200 depending on what you already have on hand. What we really like is how it’s almost entirely made out of a single 4’x8′ panel of plywood — it’s like this guy works for IKEA or something!