There’s interesting news out of Wyoming, where a coal mine was opened this week. But the fact that it’s the first new coal mine in 50 years isn’t the big news — it’s the mine’s abundance of rare earth elements that’s grabbing the headlines. As we’ve pointed out before, rare earth elements aren’t actually all that rare, they’re just widely distributed through the Earth’s crust, making them difficult to recover. But there are places where the concentration of rare earth metals like neodymium, dysprosium, scandium, and terbium is slightly higher than normal, making recovery a little less of a challenge. The Brook Mine outside of Sheridan, Wyoming is one such place, at least according to a Preliminary Economic Assessment performed by Ramaco Resources, the mining company that’s developing the deposit.

The PEA states that up to 1,200 tons of rare earth oxides will be produced a year, mainly from the “carbonaceous claystones and shales located above and below the coal seams.” That sounds like good news to us for a couple of reasons. First, clays and shales are relatively soft rocks, making it less energy- and time-intensive to recover massive amounts of raw material than it would be for harder rock types. But the fact that the rare earth elements aren’t locked inside the coal is what’s really exciting. If the REEs were in the coal itself, that would present something similar to the “gasoline problem” we’ve discussed before. Crude oil is a mixture of different hydrocarbons, so if you need one fraction, like diesel, but not another, like gasoline, perhaps because you’ve switched to electric vehicles, tough luck — the refining process still produces as much gasoline as the crude contains. In this case, it seems like the coal trapped between the REE-bearing layers is the primary economic driver for the mine, but if in the future the coal isn’t needed, the REEs could perhaps be harvested and the coal simply left behind to be buried in the ground whence it came.

Anyone old enough to remember the heyday of Heathkit probably can recall the glory that was their annual catalog. Second in importance in the geek calendar year only to the release of the Radio Shack catalog, the Heathkit catalog was highly anticipated for the incredibly diverse line of kits they offered. You could build anything from a simple transistor radio to a full-size color console TV, and everything in between. One thing you couldn’t buy from the catalog, though, was a satellite, but thanks to the rebooted Heathkit brand, you sorta-kinda can now. The solar-powered AMSAT CubeSat simulator, which appears to be approximately within the 1U spec, apart from the antennas sprouting from it, is being marketed to the STEM educational market. That’s somewhat belied by the hefty $995 price tag of the kit — for that much, you’d think it would be flyable — but the package does include a lot of extra books about CubeSat engineering, as well as some space memorabilia, including space-flown artifacts. So there’s that, at least.

Speaking of historic artifacts, remember 45 rpm record adapters? If you do, you’ll no doubt recall the frustrating search for one of these little plastic spiders that you’d snap into the big hole in the middle of a 45 record so you could play it on your LP turntable. You might also remember not being able to find one and playing a 45 without the adapter, thereby discovering what the “wow” in “wow and flutter” sounded like. Well, thanks to the wonders of the Internet, you never have to worry about not having a 45 adapter on hand, thanks to 45rpmRecordAdapters.com. The site offers all kinds of adapters in all sorts of materials, from the familiar plastic spider-style adapters that stay inside the record hole to the cylindrical or cone-shaped adapters that stay on the turntable. They’re available in different kinds of plastic as well as aluminum, and while the plastic ones don’t appear to be 3D-printed, we can see how you could easily whip up a model for one of these and quickly print it up.

Good news, everyone — it’s factory tour time again! This time, we’re taking a look inside Summit Interconnect, a quick-turn PCB manufacturer in California that specializes in low-volume but quick turnaround prototype work. This is mainly a slide show of the equipment and processes used to turn out quality PCBs fast, although there are a few short videos of the equipment at work. It’s a surprisingly hands-on process, with people doing a lot of the transportation of stack-ups between machines. We suppose that makes sense for this scale of work; it would probably be a lot more expensive to build automation that can deal with the variability in stack-ups than it is to pay a human to do it.

And finally, if you’ve ever wondered what life as a linesman would be like, you need to check out this POV video of a simple pole repair job. Aaron, from the “Bobsdecline” channel on YouTube, is a journeyman linesman in Canada who’s truly passionate about what he does and loves to share it with his audience. For this video, he donned the helmet-mounted GoPro and showed us the replacement of some broken equipment on a service pole, discovered after an unlucky squirrel knocked the power out to a customer. There’s some fantastic footage of the tools and equipment he uses while replacing the cutout, lightning arrestor, and dead-end insulators, but what gets us is how smooth Aaron’s every move is. He’s obviously done this hundreds of times, resulting in a certain amount of muscle memory, but when dealing with a 7,200-volt primary line, every motion has to be carefully considered. He still manages to make it all look silky smooth even while wearing bulky hot gloves. Face it — most of us would have probably dropped a tool at least once. Enjoy!

When [Ben Eater] talks, hackers everywhere listen. In his latest video [Ben] shows us how to make computer noises using square waves and a 6502 microprocessor.

[Ben] uses the timer in the W65C22 Versatile Interface Adapter to generate the square waves which generate a tone. He then adds support for a new BEEP command into his MS BASIC interpreter. We covered [Ben Eater]’s MS BASIC here at Hackaday back in April, so definitely check that out if you missed it.

After checking the frequency of oscillation using his Keysight oscilloscope he then wires in an 8Ω 2W speaker via a LM386 audio amplifier. We can’t use the W65C22 output pin directly because that can only output a few milliwatts of power. [Ben] implements the typical circuit application from the LM386 datasheet to drive the speaker. To complete his video [Ben] writes a program for his BASIC interpreter which plays a tune.

Thanks to [Mark Stevens] for writing in to let us know about this one. If you’re planning to play along at home a good place to start is to build your own 6502, like [Ben] did!

Both small children and cats have a certain tendency to make loud noises at inopportune times, but what if there were a way to combine these auditory effects? This seems to have been the reasoning behind the creation of the Meowsic keyboard, a children’s keyboard that renders notes as cats’ meows. [Steve Gilissen], an appreciator of unusual electronic instruments, discovered that while there had been projects that turned the Meowsic keyboard into a MIDI output device, no one had yet added MIDI input to it, which of course spurred the creation of his Meowsic MIDI adapter.

The switches in the keys of the original keyboard form a matrix of rows and columns, so that creating a connection between a particular row and column plays a certain note. [Steve]’s plan was to have a microcontroller read MIDI input, then connect the appropriate row and column to play the desired note. The first step was to use a small length of wire to connect rows and columns, thus manually mapping connections to notes. After this tedious step, he designed a PCB that hosts an Arduino Nano to accept input, two MCP23017 GPIO expanders to give it enough outputs, and CD4066BE CMOS switches to trigger the connections.

[Steve] was farsighted enough to expect some mistakes in the PCB, so he checked the connections before powering the board. This revealed a few problems, which some bodge wires corrected. It still didn’t play during testing, and after a long debugging session, he realized that two pins on an optoisolator were reversed. After fixing this, it finally worked, and he was able to create the following video.

Most of the MIDI hacks we’ve seen involved creating MIDI outputs, including one based on a Sega Genesis. We have seen MIDI input added to a Game Boy, though.