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Hackaday Links: April 18, 2021

More bad news from Mars this week, and this time not just from Perseverance. Last week the eagerly anticipated first flight of the helicopter Ingenuity was delayed for a couple of days after failing a full-speed spin-up test of its rotors. That appears to have been a bigger deal than initially thought, as it required a significant rewrite of the helicopter’s software. That meant testing, of course, and subsequent upload to the UAV, which at 174 million miles away takes a bit of doing. The good news is that they were able to complete the full-speed rotor test without the full program upload, so we’re one step closer to flight, which may take place as early as Monday morning.

Meanwhile, over at Elysium Planitia, the Mars InSight lander has troubles of its own. The geophysical laboratory, which has been trying to explore the inner structure of Mars since landing in 2018, entered an “emergency hibernation” state this week because of a lack of sufficient power generation. Unlike the radioisotope-powered Perseverance rover, InSight relies on a pair of solar panels for its electricity, and those panels are being obscured by Martian dust. The panels normally get blown clean by Martian winds, but things have been calm lately and the dust has really built up. If this seems like deja vu all over again, it’s probably because a planet-wide dust storm is what killed the plucky Opportunity rover back in 2018. Here’s hoping the wind picks up a little and InSight can get back to work.

Funny what crops up in one’s newsfeed, especially when one is responsible for putting out content that populates others’ newsfeeds. We recently took a look at the dangers of “zinc fever”, a flu-like illness that can crop up after inhaling gasses produced by molten zinc. That resulted in stumbling across an article from last year about mild steel welding fumes being classified as a human carcinogen. This comes from the Health and Safety Executive, a UK government agency concerned with workplace health issues. The release is an interesting read, and it suggests that mild steel fumes can cause not only lung cancer but kidney cancer. The announcement is mainly concerned with British workplaces, of course, but there are some interesting tidbits in there, such as the fact that welding fumes make dust particles so small that they can reach down into the very lowest reaches of lungs, the alveoli where gas exchange occurs. It’s enough to make one invest in PAPR or some kind of fume extractor.

For those of a certain vintage, our first computer was probably something that bore little resemblance to a PC or laptop. It was likely a single-board affair or something like a C64, and acquiring the essential bit of hardware usually left little in the budget for a proper monitor. Little 12″ B&W TVs were a dime a dozen, though, and easily — if grainily — enlisted into service as a monitor by way of an RF modulator. To recreate a little of that magic with modern hardware, Hackaday contributor Adam Zeloof came up with the PiMod Zero, an RF-modulator hat for the Raspberry Pi Zero that turns the component video into an NTSC analog signal. He’s open-sourced the design files, or there’s a CrowdSupply campaign for those who prefer to buy.

And finally, if you somehow traveled back in time to the 1940s with a laptop, how long would it have taken you to crack the Enigma code? Longer than you think, at least according to Dr. Mike Pound over at Computerphile, who released a fascinating video on how Enigma worked and what it took for Turing and the gang at Bletchley to crack the code. We knew some of the details of Enigma’s workings before seeing this video, but Mike’s explanation was really good. And, his explanation of the shortcut method he used to decode an Enigma message made the whole process clearer to us than it’s ever been. Interesting stuff.

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Raspberry Pi Serves Up 24 Hour Simpsons Channel

Commercial-free video on demand was every couch potato’s dream for decades, and now we’ve got it. But nostalgia has a funny way of making some folks miss the old days, even if we know it’s technically be a step backwards. Wanting to recreate the TV watching experience circa 1998, [probnot] has come up with a way to run his very own television channel.

With the Raspberry Pi and a digital modulator, he’s got the only house on the block that’s wired to show The Simpsons all day. He has absolutely no control over which episode plays next, he can’t pause it, and its in presented in standard definition (a nightmare for anyone who grew up in the Netflix era) but a familiar viewing experience for the rest of us.

Where we’re going, we don’t need HDMI.

The key to this project is the Channel Plus Model 3025 modulator. It takes the feed from the antenna and mixes in two composite video sources on user-defined channels. All [probnot] had to do was find a channel that wouldn’t interfere with any of the over-the-air stations. The modulator has been spliced into the house’s coax wiring, so any TV connected to the wall can get in on the action. There’s no special setup required: when he wants to watch The Simpsons he just tunes the nearest TV to the appropriate channel.

Providing the video for the modulator is a Raspberry Pi, specifically, the original model that featured composite video output. While the first generation Pi is a bit long in the tooth these days, playing standard definition video is certainly within its capabilities. With a USB flash drive filled with a few hundred episodes and a bit of scripting it’s able to deliver a never-ending stream direct from Springfield. There’s still that second channel available on the modulator as well, which we’re thinking could be perfect for Seinfeld or maybe The X-Files.

Interestingly, this isn’t the first time we’ve seen a Raspberry Pi used to provide a never-ending stream of The Simpsons. But compared to previous attempts which had to be directly connected to the TV, we like the idea of using the modulator and creating a more authentic experience.

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Bring Saturday Mornings Back To Life With This Cartoon Server

It was an American ritual for over four decades: wake up early on Saturday morning, prepare a bowl of sugar, and occupy the couch for four glorious hours of cartoons. The only interruptions came when the least-significant sibling had to be commanded to get up to change the channel to one of the two other networks, or when your mom decided to vacuum the TV room. It was a beautiful ritual, but now it’s gone.

Or is it? If you really want to recapture your misspent youth, you can try this Raspberry Pi multi-channel cartoon server with retro TV display. [FozzTexx] started with a yard sale 13″ Zenith set, which languished in his shop for want of a mission. When he found a four-channel video modulator, he knew he had the makings of the full channel-changing Saturday morning experience.

Four Raspberry Pis were configured to serve up four separate streams of cartoons from his Plex server, and after a late Friday night of hacking the whole thing together, each stream was ready to go live at 7:00 AM on Saturday. [FozzTexx] thought of everything — from the pre-“broadcast day” test pattern to actual commercials spliced into the cartoons to the static between the channels, it’s all there in low-definition glory. He even printed up faux TV Guide pages! You can watch a brief demo on [FozzTexx]’ Twitter feed, or you can watch the entire 2-hour Periscope feed if you’re feeling nostalgic.

[FozzTexx] chose UHF channels for his “stations,” so if you want to replicate this build it may pay to bone up on analog TV tuner basics. Or if it’s just the retro look you’re going for, this custom case inspired by a 40s TV might be nice to check out.

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