Creating a multimedia elevator ride

[Ben Peoples] works in theatrical electronics. Sounds like fun, and here’s an example of the kind of stuff he does. We’re not sure what event this installation was used for, but if the elevator ride needed something flashy just think of what the party room must have looked like. These HDTV screens on the ceiling of the elevator play different clips when the elevator is moving up or down. The challenge for [Ben] was to find a way to make it work without tapping into the elevator electronics or requiring any button presses.

The first attempt at sensing the elevator’s travel was done with an accelerometer. The problem with this approach is that an accelerometer only senses change in acceleration and this method proved to be fairly error prone. [Ben] switched over to a reflective sensor which performed quite well. Since most of these sensors will only work within about an eighth of an inch he ended up building his own with a LDR and a couple of amber LEDs.

[via Reddit]

Retrotechtacular: The Blit has given me access to the power of multiprogramming!

We normally try to be descriptive with our titles. But when that statement pops out of the narration with notable excitement it made us chuckle. This installment of Retrotechtacular is a promotional video for the Blit. It’s a graphics-based hardware terminal for Unix systems. It’s biggest boast is the ability to run (and display on screen) several different programs at once — an activity called multiprogramming. But there is also the “digitizing mouse”. On board is a 68000 microcprocessor 256k of RAM (they call it a quarter meg), and connects via RS232. The screen is 800 by 1024; that’s right, it’s a portrait orientation.

Notable in this episode are some classic eyeglass frames, and rad synthesizer sounds for scene transitions. Whatever happened to videography technique that uses a dimwitted companion to ask that all-knowing narrator stupid questions?

[Read more…]

Printing point-to-point circuits on a 3D printer

[CarryTheWhat] put up an Instructable on his endeavours in printing circuit boards for solder free electronics. He managed to print a flashlight where the only non-printed parts are a pair of batteries and a couple of LEDs.

The circuit is a weird mix of point to point and Manhattan style circuit construction; after modeling a printed plastic plate, [CarryTheWhat] added a few custom component holders to hold LEDs, batteries, and other tiny electronic bits.

To deliver power to each electronic bit, the components are tied off on blue pegs. These pegs are attached to each other by conductive thread much like wirewrap circuit construction.

Right now, the circuits are extremely simple, but they really remind us of a few vintage ham radio rigs. While this method is most likely too complex to print 3D printer electronics (a much desired and elusive goal), it’s very possible to replicate some of the simpler projects we see on Hackaday.

[CarryTheWhat] put the models and files up on GitHub if you’d like to try out a build of your own.

Arduino PIC programmer writes to 18F family

[Kirill] wrote in to share his Arduino-based PIC programmer. It is capable of writing to the 18F family of chips, including 18F2XXX and 18F4XXX. We think that’s pretty exciting because this line of chips has USB functionality and there are bootloaders out there that let you program them via USB. So if you wanted to build your own PIC dev-board (like this one) you can use your Arduino to flash the bootloader.

This post comes hot on the heels of the Arduino being used as a PIC 16F programmer. That hack has a rudimentary programming GUI, something that [Kirill] admits his lacks but has no plans to implement himself. Perhaps someone will do a little porting work to merge the projects, adding to the range of chips supported by this programming technique.

A 3D printed, electromechanical computer

If you had a machine that could print complex mechanical parts in an hour or so, what would you do? [Chris] is doing the coolest thing we can imagine and is building an electromechanical computer from 3D printed parts.

You may remember [Chris] from his efforts to getting his tiny, 1/10th scale Cray-1 supercomputer up and running. Even though he has the OS on a disk, actually booting the machine is a bit of a problem; much the same as his electromechanical computer project. Late last year we saw [Chris] building a few gears for his computer, but now he’s got a punch card reader that looks very much like a Jacquard loom.

Even though the computer doesn’t actually do anything yet, it’s amazing to think that [Chris] is building out of plastic that will run computer programs. You can check out the video of [Chris]’ video of his punch card reader after the break.

[Read more…]

Watch a shop tour through the screen of an oscilloscope

[Alan] posted a video tour of his electronics shop, but you’ll be viewing it through the green screen of an oscilloscope. The image above is a video camera filming a scope screen which displays the image of…. an oscilloscope (insert your own Yo Dawg meme here). But first he shares the technique he uses to display composite video on an oscilloscope screen.

The first three minutes of the video after the break are devoted to the video display hack. He starts with a glimpse of the breadboard circuit which takes the composite video signal and provides the necessary X, Y, and Z input signals to the scope to perform like this. He then walks through each portion of the schematic, which is based on an LM1881 video sync separator chip. The horizontal and vertical sync signals are separated by this chip, then filtered to produce ramp voltages for each to drive X and Y. The Z-axis is fed through a simple inverter circuit; Bob’s your uncle and your oscilloscope is now a TV monitor.

Of course this is not the first time this has been done. But we loved [Alan’s] presentation, and thought the shop tour was a fun way to finish off the video.

[Read more…]