Homebrew Multimode Digital Voice Modem

There’s an old saying that the nice thing about standards is there are so many of them. For digital voice modes, hams have choices of D-Star, DMR, System Fusion, and others. An open source project, the Multimode Digital Voice Modem (MMDVM), allows you to use multiple modes with one set of hardware.

There are some kits available, but [flo_0_] couldn’t wait for his order to arrive. So he built his own version without using a PCB. Since it is a relatively complex circuit for perf board, [flo_0_] used Blackboard to plan the build before heating up a soldering iron. You can see the MMDVM in action below.

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Hackaday Links: Leap Eve, 2016

The current Mac Pro is a masterpiece of design that looks like a trash can. We’ve been waiting for someone to take one of these computers and stuff a MiniITX board in there, but seeing as how the Mac Pro costs $3000, that probably won’t happen anytime soon. Here’s the solution. It’s a trash can computer case that is also too expensive for what it is. Now all we need is someone to put a big fan inside one and turn this computer into a wacky waving inflatable arm flailing tube man.

[Mike Harrison] recently got his hands on a $20,000 SPARC CPU module. This is an enormously thick board that must be dozens of layers thick. How many layers was an open question until he put the board in a CNC milling machine. The setup is pretty much what you would expect with a few lines of g-code repeated over and over. The real trick comes from using one of the outputs for lubricant to trigger the shutter release on a camera. How many layers were in the CPU module? About 30, or something like that.

Almost a year ago, we saw the latest advances in perfboard. It was a perfboard with each hole connected to rows and columns on a selectively solderable orthogonal busses. Something like that. Actually, we still can’t wrap our head around it. Now, it’s a crowdfunding campaign with a few new and useful features. There’s also a layout tool that will show you where to place your components and where to make solder bridges.

[Ray Wilson] started Music From Outer Spacethe place to learn about DIY analog synthesizers. Ray now has cancer, and as you can imagine, being a self-employed engineer specializing in analog synthesizers doesn’t provide great health coverage. [Ray]’s family set up a GoFundMe page to pay for the medical expenses.

We haven’t seen much in the land of 3D scanners, and we’re betting most of that is because they’re so expensive. The guys from CowTech have a kickstarter up for a 3D scanner that’s just $99. It’s based on the Ciclop scanner but designed around a custom Arduino shield and remains fully open source.

Remember the screen printed electroluminescent displays that were printed directly onto t-shirts from a few months ago? Now that company is working on a much cooler design: the Hackaday Jolly Wrencher. It works, but there are still a few problems: they’re setting the shirt on fire a little. Don’t worry, if these are ever reasonably safe and somewhat affordable, an EL Jolly Wrencher shirt will be in the Hackaday Store.

Need a rechargeable multimeter? It’s actually pretty easy. With an 18650 Lithium Ion cell and a 9V boost converter, this circuit will fit in most devices that need a 9V battery. To do this right, you’ll also need a USB charging port, to be used once every couple of years when the battery needs charging.

Ask Hackaday: The Latest Advances In Perfboard

It’s no secret the Hackaday tip line gets a lot of email from Kickstarter campaigns and PR firms managing Kickstarter campaigns. Most of these are terrible products. Want a five-pound battery that can’t be recharged? Yeah, stuff like that.

Every once in a while, we come across a tip that’s a completely original idea. There’s a balance between ingenuity and practicality with these ideas, and I can’t figure out where this one sits. It’s a Kickstarter for perfboard, yes, but not like any perfboard you’ve ever seen.

Busboard, or solderable breadboard
Busboard, or solderable breadboard

Before we dig into this, let’s get some definitions straight. Perfboard is a sheet with holes drilled on a 0.1″ grid. The holes are plated on both sides, and each hole is an individual electrical node. Veroboard, or stripboard is a bunch of holes on a 0.1″ grid. These holes are also plated, but all the holes in a column are a single electrical node. You can cut the tracks between holes, but the basic idea here is to reduce the number of wires needed to connect components. Busboard, seen left, is a continuation of Veroboard, and is laid out like a solderless breadboard.

And so we come to the new invention, Perf+, the perfboard reinvented. This perfboard again is a series of plated holes on a 0.1″ grid. Alongside these holes is a plated bus. This bus does not connect to any hole; instead, a little bit of solder is used to connect it to holes on the same row or column. “Selective Veroboard,” you could call it.

Now for the real trick: on one side of the board, the plated busses run vertically. On the other side of the board, the plated busses run horizontally. This means any two holes on the protoboard can be connected as one electrical node simply with a bit of solder.

If ever there was an idea you could point to and simultaneously say, “that’s clever” and “I have no idea how to use this,” there you go. I’m pretty sure this idea isn’t better than a piece of stripboard, but it is different. If you have any idea of how to used this new, strange, and otherworldly protoboard for something useful, put a note in the comments.

Finally, an Easy To Make Holder for Lithium Ion Batteries

Lithium Ion Battery holder

For projects requiring a bit more juice, the mass production of those small rectangular lithium ion batteries for cell phones, cameras and other electronics are extremely useful — the problem is, how do you mount them, short of soldering the terminals in place? With a bit of perfboard of course!

[Jason] came up with this idea when he was trying to figure out a way to mount small lithium cells for a battery fuel gauge for another one of his projects. He found if you use good quality perfboard you can use a 90 degree male pin header to contact the terminals, and a strip of female pin header as a kind of battery stop at the other end. This allows you to very snugly squeeze the battery in place — you may need to adjust the length of the male pins though in order to fine tune the fit!

Now you can add a nice wire terminal, solder up the connections, and there you have it, an easy to make, extremely useful battery holder!

A laser cutter challenge

When the Louisville hackerspace LVL1 was discussing the purchase of a new laser cutter, a member said, “I could build one before you get around to buying one.”  The gauntlet was thrown down, a challenge was set, and the race was on to build a tiny laser cutter before the hackerspace took delivery of their new laser cutter.

The mechanical aspect of the build is fairly simple. The X axis is simply a stepper motor, threaded rod and laser module mounted on a carriage. This carriage moves along the Y axis with the help of two stepper motors for either side. Everything was mounted on more perfboard than reason would suggest.

For the electronics of the project, three motor drivers were made with a few logic chips and the laser firing relay was stolen from test equipment developed for LVL1’s trans-Atlantic balloon build. Motor and laser control was handled by an Arduino to keep the build simple because the contest was over after the first laser was finished cutting a square.

LVL1 is now working on a second version of the winner of the laser cutter challenge. They’re planning on a touchscreen interface that will cut a plastic blank about the size of a credit card. We can’t wait to see the results of that build.