About Artem Litvinovich

Artem is a hacker and garage tinkerer based in Moscow. His day job is making software for a telecom company. You can check out his projects at http://orbides.org

The Daredevil Camera

June 29, 2016 By

Once upon a time I was reading a Popular Mechanics article, the title of which eludes me. Something about playing different music for different parts of a dance floor. They were describing a way to focus sound towards different people.

What struck me about the idea was that there was a way to focus sound. It was a piece of mesh of some sort, which acted as a lens for ultrasonics. This sparked an idea for what ended up being the most complex and expensive of my hobby projects to date.

Imagine using such lenses to focus sound onto a plane of microphones. Just like light in a camera. One microphone is one pixel. An ability to see sound.

duga

Duga 3 radar, image from Wikimedia commons.

I didn’t actually read Daredevil comics until much later, but those who have can see where this is going.

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Artem vs. Predator

May 12, 2016 By

I’m not sure what it was. Might have been the Predator movies, might have been something else.

Heat vision. The ability to see heat was something I wanted for a while.

Back in the old days, however, any sort of a heat vision camera cost more than I’d made in a decade.

You might think “superpower!”, but that’s not what I had in mind.

I had an idea, an image in my mind. Something that is trivial to photoshop, but is absurdly hard to actually see. Things and scenes lit up by the light emitted from a human. The glow of our heat lighting up the scene.

mwir_win

What would it take to make a picture like that? What makes a camera? And how can you make a heat-seeing camera yourself?

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Artisanal Hand-Crafted Electrons

November 23, 2015 By

Warning:  This post is a spectator view of laboratory experiments by an experienced engineer, not a DIY guide. If you try experiments like this, you do so at your own risk. It is YOUR responsibility to employ proper shielding and safety measures, and to stay in compliance with your local safety laws.

Vacuum tubes. What are they good for today? Believe it or not, they are not exactly obsolete, and can be a more efficient solution than more modern components in some applications.

Where exactly? The first thing that comes to mind is that these are good for making sound.

To start, consider an old cathode-ray-tube (CRT) TV. The CRT needs a stable voltage in the tens of kilovolts range, or the picture would flicker in size from the changes of brightness. In the early days they used a tube-based linear regulator to make it stable. For that end there were special triodes that could withstand these voltages.

2

Their time didn’t last, since at 20-30 KV they were in the soft X-ray range and putting X-ray emitters into TVs is a bad idea. I suspect that’s where the myth about cacti absorbing radiation from monitors originated.

Anyway, let’s use such a triode as an arc modulator (plasma speaker) to make our own version of “tube sound”.

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LCD Curtains

October 8, 2015 By

Once upon a time I read about Bill Gates’ smart house. And I thought: how nice would it be to have the curtains close and open automatically? Then I thought, why use curtains? Just put a big liquid crystal display (LCD) screen in the window, and use that to enable or disable the light.

Those were the days of the single LCD TV standing prominently in the big mall with a multi-thousand dollar price tag below it, so I laughed at the idea and forgot about it.

Fast forward 20 years.

Today I wanted to take a nap, and wondered how good it would be to be able to just flip a switch and turn off that annoying sun. The old idea came back. The difference is, today window-sized LCD screens are dirt cheap. People throw these TVs into the garbage once the batteries in the remote run out.

Some googling showed that there is pretty much nothing like the LCD curtains I was imagining. Some frosted/clear switchable “smart glass” and some aerospace stuff, but nothing that lets you flip a switch and block out the sunshine.

So, I dug up a screen panel from a broken laptop.

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