Hackaday Retro Edition: TRS Wiki

April 28, 2015 by Brian Benchoff 14 Comments

1977 was a special year for computing history; this year saw the release of the 8085 following the release of the Z80 a year before. Three companies would launch their first true production computers in 1977: Apple released the Apple II, Commodore the PET 2001, and Tandy / Radio Shack the TRS-80 Model I. These were all incredibly limited machines, but at least one of them can still be used to browse Wikipedia.

[Pete]’s TRSWiki is a Wikipedia client for the TRS-80 Model I that is able to look up millions of articles in only uppercase characters, and low resolution (128×48) graphics. It’s doing this over Ethernet with a very cool Model I System Expander (MISE) that brings the lowly Trash-80 into the modern era.

The MISE is capable of booting from CF cards, driving an SVGA display and connecting to 10/100 Ethernet. Connecting to the Internet over Ethernet is one thing, but requesting and loading a web page is another thing entirely. There’s not much chance of large images or gigantic walls of text fitting in the TRS-80’s RAM, so [Pete] is using a proxy server on an Amazon Web Services box. This proxy is written in Java, but the code running on the TRS-80 is written entirely in Z80 assembly; not bad for [Pete]’s first project in Z80 assembly.

The Hackaday Retro Edition is our celebration of old computers doing something modern, in most cases loading the old, no CSS or Javascript version of our site.

If you have an old computer you’d like featured, just load up the retro site, snap some pictures, have them developed, and send them in.

Retrotechtacular: Radar Jamming

April 28, 2015 by Kristina Panos 23 Comments

It’s been said that the best defense is a good offense. When aloft and en route to deliver a harmful payload to the enemy, the best defense is to plan your approach and your exit carefully, and to interfere with their methods of detection. If they can’t find you, they can’t shoot you.

As of May 1962, the United States military was using three major classifications of radar jamming technology as described in this week’s film: the AN/ALQ-35 multiple target repeater, the AN/ALQ-55 communications link disrupter, and the AN/ALQ-41 and -51 track breakers. The most important role of these pieces of equipment is to buy time, a precious resource in all kinds of warfare.

The AN/ALQ-35 target repeater consists of a tuner, pulse generator, transmitter, and control panel working in concert to display multiple false positives on the enemy’s PPI scopes. The unit receives the incoming enemy pulse, amplifies it greatly, repeats it, and sends them back with random delays.

The AN/ALQ-55 comm disrupter operates in the 100-210MHz band. It distinguishes the threatening enemy communication bands from those of beacons and civilians, evaluates them, and jams them with a signal that’s non-continuous, which helps avoid detection.

Finally, the AN/ALQ-41 and -51 track breakers are designed to break enemy lock-on and to give false information. It provides simultaneous protection against pulse ranging, FM-CW, conical, and monopulse radar in different ways, based on each method’s angle and range.

Continue reading “Retrotechtacular: Radar Jamming” →

Hackaday Links: April 26, 2015

April 26, 2015 by Brian Benchoff 11 Comments

In case you haven’t heard, we’re giving away a trip to space. We have $50,000 to promote giving away a trip to space too, and this week we’re giving away some OSH Park gift cards. If you have a project that’s held together with hot glue on a 40-year-old piece of perf board, add a project log describing how you need some free PCBs.

A few months ago, some guy in Texas found the original molds for the Commodore 64C, the Plus/4 and the 128. That discovery turned into one of the best examples of what Kickstarter can do. Now, new keycaps are being manufactured with an Indiegogo campaign. If you’re waiting on your C64c case to be pressed out of a mold, this is not the time to think about the sunk cost fallacy. They’re not Cherry MX compatible, but they will work with just about every version of the C64. Not bad for under €20.

The UK has a fabulously rich history of ancient melee weapons, ranging from the flail to the mace and a bunch of odd bladed weapons used by the Scots. This tradition was passed down to the UK mains plug, the single most painful plug to step on. Apple just released a USB charger with a folding UK mains plug and [oliver] did a teardown on it.

For St. George’s Day in Catalonia, there’s a tradition of giving roses to women, and books to men. [Nixieguy] has all the books he could want, and would prefer to receive a rose. Bucking tradition, he made himself a rose from a punch card. It’s the closest he’s going to get to ‘@}-\—’. A few years ago, he carved a rose out of a 10mm LED.

Finally, a decent tutorial on how to grow your own SMD components.

Need to take apart a cellphone? Use acetone! Need the phone to work after you take it apart? Ummmm….

The Dayton Hamvention is just three weeks away! Yes, the same weekend as the Bay Area Maker’s Faire, which means most of the Hackaday crew will be elsewhere, but I hear [Chris Gammell] will be there putting Parts.io stickers on everything. By the way, I’m looking for a Tek PM203 Personality Module for a 68000 64-pin PDIP.

Hacklet 44 – Teardowns

April 25, 2015 by Adam Fabio 14 Comments

Just about every hacker, maker and tinkerer out there received their early education the same way: A screwdriver in one and a discarded bit of electronics in the other. There is no better way to find out how something works than cracking it open and examining each piece. In recent years, teardown videos have become popular on YouTube, with some of the great examples coming from users like [EEVblog], [mikeselectricstuff], and [The Geek Group]. This week’s Hacklet is all about the best teardown projects on Hackaday.io!

We start with [zakqwy] and his Savin C2020 Teardown. Photocopiers (and multifunction machines) are the workhorses of the modern office. This means there are plenty of used, abused, and outdated photocopiers available to hackers. [Zakqwy] got this monster when it started misbehaving at his office. Copiers are a venerable cornucopia of motors, gears, sensors (lots and lots of breakbeam sensors) and optics. The downside is toner: it’s messy, really bad to breathe, and if you don’t wear gloves it gets down into the pores of your skin, which takes forever to get out. [Zakqwy] persevered and found some awesome parts in his copier – like an Archimedes’ screw used to transport black toner.

Next up is [Bob Blake] with Belkin WeMo Insight Teardown. [Bob] wanted a WiFi outlet, but wasn’t about to plug something in to both his power grid and his network without taking it apart first. [Bob] did an awesome job of documenting his teardown with lots of great high resolution photos – we love this stuff! He found a rather well thought out hardware design. The Insight has 3 interconnected PCBs inside. The power switching and supply circuits are all on one board. It includes slots and the proper creep distances one would expect in a design that will be carrying 120V AC mains power. A small daughter board holds an unknown chip – [Bob] is guessing it is the power sensing circuitry. A third board a tucked in at the top of the module holds the main CPU, a Ralink/MediaTek RT5350F SoC, RAM, and the all important WiFi antenna.

[Drhatch] took things into the danger zone with an X-ray Head Teardown. We’re not sure if [Drhatch] is a real doctor, but he does have a Heliodent MD dental X-ray head. Modern X-ray machines are generally radiation safe if they’re not powered up. Radiation isn’t the only dangers to worry about though – there are latent charged capacitors and cooling oils which may contain nasty chemicals like PCBs, among other things. [Drhatch] found some pretty interesting design decisions in his X-ray head. The tube actually fires through the cylindrical high voltage transformer. This means the transformer acts as a beam collimator, focusing the X-ray beam down like a lens. He also found plenty of lead shielding. Interestingly there are two thickness of lead in the housing. Shielding close to the tube is 1 mm thick, while shielding a bit further away is only 0.7 mm thick.

Finally, we have [danielmiester] with Inside a 3ph AC Motor Controller(VFD). [Daniel] tore down a Hitachi Variable-Frequency Drive (VFD) with the hopes of creating a frequency converter for a project. These high voltage, high power devices have quite a bit going on inside, so the conversion became a teardown project all its own. VFDs such as this one are used in industry to drive high power AC motors at varying speeds efficiently. As [Daniel] says, the cheaper ones are ” just really fancy PWM modules”. Handling 1.5 kW is no joke though. This VFD had a large brick of power transistors potted into its heat sink. The controller board was directly soldered to the transistors, as well as the rectifier diodes for the DC power supply. [Daniel] was doing some testing with the unit powered up, so he built a custom capacitor discharge unit from 3 C7 Christmas lights. Not only did they keep the capacitors discharged, they provided an indication that the unit was safe. No light means no charge.

Not satisfied? Want more teardown goodness? Check out our freshly minted Teardown List!

That’s about all the time we have for this week’s Hacklet. As always, see you next week. Same hack time, same hack channel, bringing you the best of Hackaday.io!

$50k In Play: Thirty Projects Will Win Custom PCBs This Week

April 24, 2015 by Mike Szczys 30 Comments

This week we’re giving away $1500 in OSH Park codes to thirty different projects. Submit your project to the 2015 Hackaday Prize now!

$50,000 over the next 17 weeks!

For each of the last four weeks we’ve awarded prize packages to three projects just for submitting ideas. Now it’s time to crank up the rewards. Over the next 17 weeks we will give away $50,000 in prizes. We’re kicking off the week by giving $50 OSH Park codes to 30 different projects.

Of course this is just the tip of the iceberg. This year’s prizes total half a million dollars, with a trip into space for the Grand Prize winner and $100,000 for the Best Product prize. Sitting this one out would be a huge mistake!

You need to post your project on Hackaday.io and officially submit it to the 2015 Hackaday Prize, which means clicking the “Submit-To” button on the left sidebar of your entry (shown below). You can confirm that you’re in the running by looking for the 2015 Hackaday Prize logo on your project gallery picture. Here you can see [castvee8] has submitted the Binary fuel tank, do you think it’s ready for a custom PCB?

To give yourself the best chance at winning, publish a new project log this week that outlines the PCB work your want to do for the entry. We’ll be looking for those as we judge the prizes that are most ready to begin (or advance) their hardware build.

OSH Park offers double-layer boards for $5 per square-inch and you get 3 copies of the board with shipping included. This $50 prize will land you quite a bit of board space. Get started now, you need to have your projects submitted by the morning of Wednesday, April 29th.

The 2015 Hackaday Prize is sponsored by:

Crowdfunding Follies: $100 To Disprove Isaac Newton

April 23, 2015 by Brian Benchoff 170 Comments

Are satellites fake? Nobody knows, because no one has done an experiment to determine if rocket engines will produce thrust in a vacuum. At least that’s what this Kickstarter says, and it’s asking for $100 to test multiple types of rocket engines in an enclosed, evacuated chamber.

Anyone who has thought about this problem for half a second will tell you yes, rocket engines will work in a vacuum. It’s an application of Newton’s Third Law of Motion; if you explode fuel and dump it out the back of a rocket, the rocket will go forward. Rocket engines don’t push against air.

Strap in, because this one gets better. In a video linked to from the Kickstarter Campaign, satellites do not exist. This is because gas molecules in the thermosphere can reach 2,500 °C, hot enough to melt the metal satellites are made of. Never mind that the 2,500 °C figure is only for individual gas molecules; the atmosphere at these altitudes is so rarefied, there isn’t much contact with matter. Oh, second point: have you ever realized that a Google image search of the word ‘satellite’ mostly shows illustrations and renders? It’s not because to take a picture of a satellite in orbit would require two satellites flying in formation; no, it must be because satellites don’t exist. It gets better from there.

Retrotechtacular: Stateside Assembly And Launch Of V-2 Rockets

April 21, 2015 by Kristina Panos 28 Comments

At the end of World War II, the United States engaged in Operation Paperclip to round up German V-2 rockets and their engineers. The destination for these rockets? White Sands Proving Grounds in the New Mexico desert, where they would be launched 100 miles above the Earth for the purpose of high altitude research.

This 1947 War Department Film Bulletin takes a look inside the activities at White Sands. Here, V-2 rockets are assembled from 98% German-made parts constructed before V-E day. The hull of each rocket is lined with glass wool insulation by men without masks. The alcohol and liquid oxygen tanks are connected together, and skins are fitted around them to keep fuel from leaking out. Once the hull is in place around the fuel tanks, the ends are packed with more glass wool. Now the rocket is ready for its propulsion unit.

In the course of operation, alcohol and liquid oxygen are pumped through a series of eighteen jets to the combustion chamber. The centrifugal fuel pump is powered by steam, which is generated separately by the reaction between hydrogen peroxide and sodium permanganate.

A series of antennas are affixed to the rocket’s fins. Instead of explosives, the warhead is packed with instruments to report on high altitude conditions. Prior to launch, the rocket’s tare weight is roughly five tons. It will be filled with nine tons of fuel once it is erected and unclamped.

At the launch site, a gantry crane is used to add the alcohol, the liquid oxygen, and the steam turbine fuels after the controls are wired up. The launch crew assembles in a blockhouse with a 27-foot-thick roof of reinforced concrete and runs through the protocol. Once the rocket has returned to Earth, they track down the pieces using radar, scouting planes, and jeeps to recover the instruments.

Thanks for the tip, [Thomas].

Retrotechtacular is a weekly column featuring hacks, technology, and kitsch from ages of yore. Help keep it fresh by sending in your ideas for future installments.