Supercon 2022: Sam Mulvey Shows You How To FM Radio

December 15, 2022 by Elliot Williams 19 Comments

Sam Mulvey built his own radio station in Tacoma, WA. Is there a better way to meld ham radio practice with a colossal number of DIY electrical and computer projects? Sam would say there isn’t one! This 45-minute talk is basically the lessons-learned review of setting up KTQA 95.3 – the radio station on the hill.

Sam starts out the talk by introducing you to LPFM. And maybe you didn’t know that there’s a special type of license issued by the US FCC allowing non-profit community radio stations up to 100 W, covering an radius of around 5 km. It’s like running a pirate radio station, but by jumping through a few legal hoops, made legal.

Trash on the Radio

Putting a radio station together on a budget requires a ton of clever choices, flexibility, and above all, luck. But if you’re willing to repair a busted CD player or turntable, scrounge up some used computers, and work on your own amplifiers, the budget doesn’t have to be the limiting factor.

Being cheap means a lot of DIY. For instance, Sam and friends made a custom console to support all the gear and hide all the wiring. Some hot tips from the physical build-out: painted cinderblocks make great studio monitor stands, and Cat-5 can carry two channels of balanced audio along with power, with sufficient isolation that it all sounds clean. Continue reading “Supercon 2022: Sam Mulvey Shows You How To FM Radio” →

Australia’s Soft Plastic Recycling Debacle

December 15, 2022 by Zoe Skyforest 80 Comments

We’ve all been told to cut back on waste to help prevent environmental crisis on Earth. Reducing waste helps reduce the need to spend time and energy digging up fresh materials, and helps reduce the amount of trash we have to go out and bury in the ground in landfills. Recycling is a big part of this drive, allowing us to divert waste by reprocessing it into fresh new materials.

Sadly, though, recycling isn’t always as magical as it seems. As Australia has just found out, it’s harder than it sounds, and often smoke and mirrors prevent the public from understanding what’s really going on. Here’s how soft plastic recycling went wrong Down Under.

Continue reading “Australia’s Soft Plastic Recycling Debacle” →

The Story Behind The TVGuardian Curse Catcher

December 14, 2022 by Chris Lott 23 Comments

The recent flurry of videos and posts about the TVGuardian foul language filter brought back some fond memories. I was the chief engineer on this project for most of its lifespan. You’ve watched the teardowns, you’ve seen the reverse engineering, now here’s the inside scoop.

Gumby is Born

TVG Model 101 Gumby (Technology Connections)

Back in 1999, my company took on a redesign project for the TVG product, a box that replaced curse words in closed-captioning with sanitized equivalents. Our first task was to take an existing design that had been produced in limited volumes and improve it to be more easily manufactured.

The original PCB used all thru-hole components and didn’t scale well to large quantity production. Replacing the parts with their surface mount equivalents resulted in Model 101, internally named Gumby for reasons long lost. If you have a sharp eye, you will have noticed something odd about two parts on the board as shown in [Ben Eater]’s video. The Microchip PIC and the Zilog OSD chip had two overlapping footprints, one for thru-hole and one for SMD. Even though we preferred SMD parts, sometimes there were supply issues. This was a technique we used on several designs in our company to hedge our bets. It also allowed us to use a socketed ICs for testing and development. Continue reading “The Story Behind The TVGuardian Curse Catcher” →

Hyundai To Lead US Market For Hydrogen Fuel Cell Trucks

December 13, 2022 by Zoe Skyforest 96 Comments

Hydrogen has long been touted as a potential fuel of the future. While it’s failed to catch on in cars as batteries have taken a strong lead, it still holds great promise for larger vehicles like trucks.

Hyundai have been working diligently in this space over the last few years, with its Xcient line of fuel-cell powered trucks. It’s set to dominate the world of hydrogen trucking in the US as it brings a fleet of vehicles to California next year.

Continue reading “Hyundai To Lead US Market For Hydrogen Fuel Cell Trucks” →

All About USB-C: Cable Types

December 13, 2022 by Arya Voronova 51 Comments

USB-C cables and connectors: these are controversial topics, and rightfully so – I don’t want to pull any punches. I will also show you that things don’t have to be that bad for you, as long as you’re willing to apply a few tricks and adjust your expectations.

Wild West of Wiring

You might have a bunch of USB-C cables, and they all might look exactly the same, but you’ve likely experienced that they’re not the same internally, and often there’s not a label in sight. Yes, it’s pretty bad, and one could argue it’s getting worse.

I’d like to clarify that I’m only talking about USB C male – USB C male cables here. While cables like USB-A to USB-C are popular, they are quite simple; you get USB 2.0 or USB 3.0 data and 2 A of current at most, and the USB-C plug is usually hardwired as “host, will supply five volts”, which is defined by a pullup resistor. Also, while cables like “Type-C to DisplayPort” might look like cables at a glance, they are adapters with a meaningful amount of active circuitry in them.

Purely following the specification, there used to be six types of USB-C to USB-C cables out there. Then, it became eight. Now, I’m afraid, there’s twelve of them, purely following the spec, and there’s way more when counting all the out-of-spec cables. Good news is – for most of the time, majority of these cables will be suitable for simple tasks like charging and data transfer, and situations where you need a very specific cable are going to be rare enough. Still, let’s go through it, and you’ll see that they’re easier to tell apart than it might look. Continue reading “All About USB-C: Cable Types” →

Battery Engineering Hack Chat

December 12, 2022 by Dan Maloney 7 Comments

Join us on Wednesday, December 14 at noon Pacific for the Battery Engineering Hack Chat with Dave Sopchak!

Of all the things driving technology forward, you’d have to say that the ability of chip makers to squeeze more complex circuits than ever onto silicon has to rank right up there. And while that’s no doubt true, it only tells a part of the story. For our money, though, the advancements in battery technology over the last 30 years or so are the real champ, because without compact, cheap, energy-dense batteries, almost none of the cool stuff we see today, from smartphones to electric vehicles, would be practical.

Battery technology has come a long way from the days when carbon-zinc and nickel-cadmium cells were kings. New chemistries, better materials and methods, and engineering improvements have all contributed to incredibly powerful, incredibly compact batteries that make applications nobody could have thought of just a few decades ago possible.

Dave Sopchak has been in the thick of battery engineering since taking a doctorate in electrochemistry from Case Western Reserve. Since then he has worked at several fuel cell start-ups, and is now working on a lithium-air battery that sounds really interesting. We’ve asked him to help us wrap up the 2022 Hack Chat series with a discussion on battery engineering, with a focus on upcoming technologies and advancements that could really put some power in your pocket.

Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, December 14 at 12:00 PM Pacific time. If time zones have you tied up, we have a handy time zone converter.

Students Rebel Against Heat-Sensing Crotch Monitor Surveillance Devices

December 12, 2022 by Zoe Skyforest 180 Comments

Surveillance has become a ubiquitous part of modern life. Public spaces are dotted with CCTV cameras inside and out. Recent years have seen the technology spread to the suburbs with porch cameras spreading the eye of big tech and law enforcement ever further.

Outside of mere cameras, companies are rushing to develop all manner of new devices to surveil individuals, too. One such device intended to track students quickly drew the ire of scholars at Northeastern University, and the cohort fought back.

Continue reading “Students Rebel Against Heat-Sensing Crotch Monitor Surveillance Devices” →