Citizen Scientist: Hedy Lamarr

For all the destruction and human misery unleashed during World War II, it was also a time of incredible creativity and ingenuity. In America, it was a time when everyone wanted to pitch in. Young men and women enlisted and were shipped overseas, and those left behind kept the factories running full tilt. Even Hollywood went to war, with its steady output of films that gave people a little glamour and provided an escape from the horror and loss of the war. Hollywood stars lined up to entertain troops and raise money for the war effort, and many joined up and fought too.

But one Hollywood star made an unconventional contribution to the war effort, and in the process proved that beauty and brains are not always mutually exclusive. This is the story of Hedy Lamarr, movie star and inventor.

“The Most Beautiful Woman in the World”

By the time she was 23 in 1937, Hedwig Eva Maria Kiesler was a genuine film star in her native Austria. She was also trapped in an unhappy marriage to a rich and powerful Austrian munitions magnate, Fritz Mandl. Hedy was miserable as a trophy wife, adorning the dining room as her husband entertained rich and powerful guests – including Mussolini and Hitler – over long dinners in one of his mansions. They dismissed her; clearly a woman so beautiful could have nothing else to offer, an empty head perched on a graceful neck. But she was far from stupid, and while her husband discussed business with the men who were building the Axis arsenal, Hedy listened and learned.

Continue reading “Citizen Scientist: Hedy Lamarr”

Resurrecting Duckhunt

Bringing old things back to life holds a great sense of joy for most people. The never ending pursuit of recapturing our youth leads us down roads we’ve long forgotten. Along the way, we tend to bump into forgotten memories which jostle other forgotten memories which allows us to relive happy times we haven’t thought of in years, sometimes even decades. For some, the roar of a 351 small block sweeps them back to high school and the fast nights of cruising down main street with the FM radio cranked up as high as it would go.  For those of us who were born in the 80’s and 90’s, video games can bring back such memories. Who among us can forget our first encounter with Link, the elegant theme music of Final Fantasy or up-up-down-down-left-right-left-right-b-a-select-start?

Advances in processor technology has allowed us to relive our favorite games via emulators – programs that emulate processors of older computers. The games are ‘dumped’ from the ROM chips (where they are stored) into files. These game files can then be loaded into the emulator program, which allows you to play the game as if you were playing it on the original system.

Guts of NES Zapper

Technology is truly a beautiful thing. It allows us to move forward, allows us to do today that which was not possible yesterday. There are a few cases, however, where this paradigm does not hold true. One of these has to do with the Nintendo Entertainment System and its “Zapper” gun controller. The NES was the most popular game console of its time, and rightfully so. From the minds of Nintendo engineers, programmers and audio experts came some of the best video games ever made. Unfortunately, some of these great games cannot be played on your Raspberry Pi favorite emulator due to the incompatibility of the Zapper gun and modern digital monitors.  None of us can forget the fun that Duckhunt brought. The game came as standard issue with all NES systems, so we’ve all played it. But its nostalgia is currently entombed by a technological quirk that has yet to be solved.

From one hacker to another – this can no longer be tolerated. First, we’re going to learn how the Zapper works and why it doesn’t work with digital displays. Then we’re going to fix it.

Continue reading “Resurrecting Duckhunt”

Eyedrivomatic Wins the 2015 Hackaday Prize

Update: We’ve published an in-depth article about The Gaze-Controlled Wheelchair that Won the Hackaday Prize.

Eyedriveomatic are the Grand Prize winners of the 2015 Hackaday Prize. The winners were just announced on stage at the Hackaday Superconference, and awarded by the prize Judges. Eyedriveomatic is a non-invasive method of adding eye-control to powered wheelchairs. Many times these wheelchairs are rented and permanent alterations cannot be made. This inexpensive and easily adaptable hardware has the power to improve life for those who need more options for controlling powered wheelchairs.

We will be publishing more information about this year’s winners in the coming week. The full standings are listed below. Please check out all of the 2015 Hackaday Prize Finalist and the Best Product Finalists.

Continue reading “Eyedrivomatic Wins the 2015 Hackaday Prize”

Seeking Distinct Hardware Passion

This is it, the Hackaday SuperConference blasts into existence tomorrow. You should be there.

Hardware is passion. Hardware is art. Hardware is creation. Hardware is life. This is your mantra and this weekend is your one chance to connect in person with your community. At this very moment the people presenting 30+ spectacular hardware talks and hands-on workshops are headed to San Francisco to make it happen. They are joined by hundreds of Hackers, Designers, Engineers, Artists, and other Bohemians that make up something unique: a hardware conference that is actually about hardware creation.

You need to be a part of the SuperCon. It runs Saturday and Sunday at Dogpatch Studios. If you can’t make it for both days, block out your Saturday night for the Hackaday Prize Party. Starting at 5:30pm you can catch [Sprite_TM’s] talk, join a fireside chat with MythBusters veteran [Grant Imahara], be there live for the 2015 Hackaday Prize and Best Product award announcements, and then enjoy dinner and the celebration afterward. There is no charge to attend the Prize Party.

There is no better way to spend time than by exercising your passion. Don’t let the Hackaday SuperCon pass you by.

The 2015 Hackaday Prize is sponsored by:

Code Craft – Embedding C++: Timing Virtual Functions

Embedded C developers shy away from C++ out of concern for performance. The class construct is one of their main concerns. My previous article Code Craft – Embedding C++: Classes explored whether classes cause code bloat. There was little or no bloat and what is there assures that initialization occurs.

Using classes, and C++ overall, is advantageous because it produces cleaner looking code, in part, by organizing data and the operations on the data into one programming structure. This simple use of classes isn’t the raison d’etre for them but to provide inheritance, or more specifically polymorphism, (from Greek polys, “many, much” and morphē, “form, shape”).

Skeptics feel inheritance simply must introduce nasty increases in timing. Here I once more bravely assert that no such increases occur, and will offer side-by-side comparison as proof.

Continue reading “Code Craft – Embedding C++: Timing Virtual Functions”

Your First GNU Radio Receiver with SDRPlay

Although GRC (the GNU Radio Companion) uses the word radio, it is really a graphical tool for building DSP applications. In the last post, I showed you how you could experiment with it just by using a sound card (or even less). However, who can resist the lure of building an actual radio by dragging blocks around on a computer screen?

For this post and the accompanying video, I used an SDRPlay. This little black box has an antenna jack on one end and a USB port on the other. You can ask it to give you data about a certain area of the RF spectrum and it will send complex (IQ) data out in a form that GRC (or other DSP tools) can process.

The SDRPlay is a great deal (about $150) but if you don’t want to invest in one there are other options. Some are about the same price (like the HackRF or AirSpy) and have different features. However, you can also use cheap TV dongles, with some limitations. The repurposed dongles are not as sensitive and won’t work at lower frequencies without some external help. On the other hand, they are dirt cheap, so you can overlook a few little wrinkles. You just can’t expect the performance you’ll get out of a more expensive SDR box. Some people add amplifiers and converters to overcome these problems, but at some point it would be more cost effective to just spring for a more expensive converter.

Continue reading “Your First GNU Radio Receiver with SDRPlay”

Getting Started with GNU Radio

Software Defined Radio (SDR)–the ability to process radio signals using software instead of electronics–is undeniably fascinating. However, there is a big gap from being able to use off-the-shelf SDR software and writing your own. After all, SDRs require lots of digital signal processing (DSP) at high speeds.

Not many people could build a modern PC from scratch, but nearly anyone can get a motherboard, some I/O cards, a power supply, and a case and put together a custom system. That’s the idea behind GNU Radio and SDR. GNU Radio provides a wealth of Python functions that you can use to create sophisticated SDR application (or, indeed, any DSP application).

If Python is still not up your alley (or even if it is), there’s an even easier way to use GNU Radio: The GNU Radio Companion (GRC). This is a mostly graphical approach, allowing you to thread together modules graphically and build simple GUIs to control you new radio.

Even though you usually think of GRC as being about radios, it is actually a good framework for building any kind of DSP application, and that’s what I’ll show you in the video below. GRC has a signal generator block and interfaces to your sound card. It even has the ability to read and write data to the file system, so you can use it to do many DSP applications or simulations with no additional hardware.

UPDATE: Don’t miss the follow-up post that uses SDRPlay to build a GNU Radio based receiver.

Continue reading “Getting Started with GNU Radio”