Making Asteroids Miniature

September 5, 2013 by Brian Benchoff 20 Comments

Asteroids

Mini arcade cabinet builds are fairly common, but we’ve never seen anything like [Jurgen]’s mini vector Asteroids cabinet that takes an original Asteroids circuit board and a true vector monitor and shrinks it down to table top size.

Unlike the raster monitors of a later generation’s arcade games, the original Asteroids cabinet used a vector monitor just like one would find in an oscilloscope. [Jurgen] found the perfect CRT in, of all places, a broken Vectrex console. The video circuitry in the Vectrex was rather primitive and the beam deflection was far too slow for the video signals generated by the Asteroids PCB. To get around this, [Jurgen] added a custom XY driver board. While the Asteroids game – and other vector Atari games – were designed for a screen with 1 MHz of bandwidth, [Jurgen] found that 300 kHz was ‘good enough’ to display proper Asteroids graphics.

While the cabinet isn’t a miniaturized version of any proper cabinet, [Jurgen] did manage to build a rather nice looking case for his luggable version of Asteroids. The exposed PCB on the back is a great touch, and an awesome project for any ancient video game aficionado.

[Ken Shirriff] Completely Reverse Engineers The 1974 Sinclair Scientific Calculator

August 30, 2013 by Mike Szczys 46 Comments

Wow. Seriously… Wow! The work [Ken Shirriff] put into reverse engineering the Sinclair Scientific is just amazing. He covers so much; the market forces that led [Clive Sinclair] to design the device with an under-powered chip, how the code actually fits in a minuscule amount of space, and an in-depth look at the silicon itself. Stop what you’re doing and read it right now!

This calculator shoe-horned itself into the market when the HP-35 was king at a sticker price of $395 (around $1800 in today’s money). The goal was to undercut them, a target that was reached with a $120 launch price. They managed this by using a Texas Instruments chip that had only three storage registers, paired with a ROM totaling 320 words. The calculator worked, but it was slow and inaccurate. Want to see how inaccurate? Included in the write-up is a browser-based simulator built from the reverse engineering work. Give it a try and let us know what you think.

Now [Ken] didn’t do all this work on his own. Scroll down to the bottom of his post to see the long list of contributors that helped bring this fantastic piece together. Thanks everyone!

[Thanks Ed]

75 Controllers, One Gaming System

August 24, 2013 by Eric Evenchick 14 Comments

This gaming cabinet lets two players select games from a wide array of consoles and play them using the original controllers. [Patrice] built it around his Multi Video Games System 2, which converts each of the 75 controllers to a common format. Players pick controllers from the display case, plug in an HD-15 connector, and choose the game they want to play. The cabinet contains a PC that runs a variety of emulators, and uses HyperSpin as a menu system.

Using adapters, the converted controllers can also be used on other game systems, tablets, or smartphones. [Patrice] claims that they’ll work across 110 different game systems. A full list of the controllers and systems is shown here.

This cabinet is definitely one of the most comprehensive video game installations we’ve seen, and the display case of controllers looks fantastic. Check out a video of the system and some controller porn after the break.

Continue reading “75 Controllers, One Gaming System” →

Rotary Phone Museum Exhibit

August 21, 2013 by Mike Szczys 41 Comments

dial-telephone-museum-exhibit [David Burroughs] wrote in to share this dial telephone museum exhibit he built and we’re glad he did because we love interactive museum hacks. He mentions that it’s not really tied to the theme of the Roads and Rails Museum in which it’s installed. But when we think of railroad history we also think of telegraph. And that’s just a hop, skip, and a jump from telephones.

The display allows museum goers to play with the rotary dial on the phone. The box next two it contains a 10-position relay increment switch. So each pulse from the dial increments the switch. There’s a satisfying click, a moving arm, and different colored LEDs which highlight the inner workings. An Arduino board monitors the phone, displaying the dialed number on a seven segment display then incrementing the relay.

We figure the interesting part is to see that telephony used to use mechanical switching like this. But the video below includes a story about the kid who asked how you carried this phone around. This brings to mind the phrase “hang up the phone”, which doesn’t have the same literal meaning it used to.

Continue reading “Rotary Phone Museum Exhibit” →

Hacking Coin Collection

August 20, 2013 by Eric Evenchick 36 Comments

Devices that collect coins for payment typically use standardized coin acceptors like the one shown here. These devices use a protocol called ccTalk to let the system know what coins were inserted. [Balda] has built tools for implementing the ccTalk protocol to let you play around with the devices. He also gave a talk at DEF CON (PDF) about the protocol.

[Balda] got started with ccTalk because he wanted to add a coin acceptor to a MAME cabinet, and had a coin acceptor. His latest project converts ccTalk to standard keyboard keystrokes using a Teensy. The MAME cabinet can then interpret these and add to the player’s credits.

There’s two interesting sides to this project. By providing tools to work with ccTalk, it’s much easier to take a used coin acceptor off eBay and integrate it into your own projects. On the other hand, these acceptors are used everywhere, and the tools could allow you to spoof coins, or even change settings on the acceptor.

Tearing Down An Ultrasound Machine From 1963

August 18, 2013 by Brian Benchoff 7 Comments

hehsiemens

Vintage electronics are awesome, and old medical devices doubly so. When [Murtaugh] got his hands on an old ultrasound machine, he knew he had to tear it apart. Even if he wasn’t able to bring it back to a functional state, the components inside make for great history lesson fifty years after being manufactured.

This very primitive ultrasound machine was sold by Siemens beginning in 1963 as a, “diagnostic ultrasound unit for the quick evaluation of cerebral hemorrhage after accidents.” This is barely into the era of transistors and judging from [Murtaugh]’s teardown, nearly the entire device is made of vacuum tubes, capacitors, and resistors. The only solid state component in this piece of equipment is a bridge rectifier found in the power supply. Impressive stuff, even today.

In the end, [Murtaugh] decided this device wasn’t worth repairing. There were cracks all the way through a PCB, and he didn’t have any of the strange proprietary accessories anyway. Still, this junkyard score netted [Murtaugh] a bunch of old tubes and other components, as well as a nifty CRT that came with a wonderful ‘Made in West Germany’ label,.

Reverse Engineering The Die Of A ULN2003 Transistor Array

August 16, 2013 by Mike Szczys 9 Comments

uln2003-die-reverse-engineering

We’re no strangers to looking at uncapped silicon. This time around it’s not just a show and tell, as one transistor form a ULN2003 chip is reverse engineered.

The photo above is just one slice from a picture of the chip after having its plastic housing remove (decapped). It might be a stretch to call this reverse engineering. It’s more of a tutorial on how to take a functional schematic and figure out how each component is placed on a photograph of a chip die. Datasheets usually include these schematics so that engineers know what to expect from the hardware. But knowing what a resistor or transistor looks like on the die is another story altogether.

The problem is that you can’t just look at a two dimensional image like the one above. These semiconducting elements are manufactured in three dimensions. The article illustrates where the N and P type materials are located on the transistor using a high-res photo and a reference diagram.

If you want to photograph your own chip dies there are a few ways to decap them at home.