Ordering prototypes like they were fast food

Made To Spec: The Coming Age Of Prototyping As A Service

December 8, 2021 by 39 Comments

In the last decade, the price for making a single PCB plummeted. And we’ve featured tons of hacks with boards hailing from places like OSH Park or Seeed Studio. But this phenomenon isn’t isolated, and all sorts of one-off prototyping services are becoming cheaper and looking to satiate both hobbyist and engineer alike.

Today, I want to blow the lid off a few places offering one-off mechanical prototyping services. I’ll take us through some history of how we got here, introduce a few new players, and finally highlight some important tradeoffs before you start ordering bespoke aluminum parts straight to your doorstep.

Now go get your ANSI Z87+ safety glasses, and let’s get started.

Continue reading “Made To Spec: The Coming Age Of Prototyping As A Service” →

Four Band Digital HF SDR Transceiver Offers High Performance For Only $60

December 8, 2021 by 31 Comments

Amateur radio is a hobby that is often thought of as being exclusive to those with a healthy expendable income. In recent years however, the tides have turned. Cheap microcontrollers and signal generators have helped turned things around, and the $60 USD QDX from QRP Labs goes even further by sending the performance/price ratio through the roof. You can see more details in the video below the break.

The QDX is the creation of [Hans Summers] who is well known for producing affordable high performance amateur radio kits that are focused on low power transmission, called “QRP” in ham radio parlance. What is it? It’s a pocket sized four band (80, 40, 30, 20 Meters) software defined radio (SDR) that is designed to be used with some of the most popular digital radio modes: FT8 and JS8Call, as well as any other FSK based mode such as RTTY. It’s also been tested to work well (and within spec) on 60 Meters.

While classic radios have to be connected to a computer through a special hardware interface, the QDX is designed to connect directly to a computer through a standard USB A>B cable. CAT control, PTT, and Audio are all handled directly by the QDX, and no special interface is needed. While the radio is essentially plug and play, configuration, testing, and troubleshooting can be done by connecting to the QDX’s unique serial console, which among other things contains a text based waterfall. For those who want to run their own SDR receiver, I/Q output can be sent directly through the sound card.

Now for the bad news: due to global chip shortages, the QDX is out of stock at the moment, and there’s no telling when they might start shipping again. QRP Labs is looking to source parts wherever they can to get more of the units made, but of course, so is everyone else right now. Continue reading “Four Band Digital HF SDR Transceiver Offers High Performance For Only $60” →

Rubber Tyres Before There Were Tyres

December 8, 2021 by 24 Comments

Sometimes there is pleasure in watching an expert demonstrating his craft, particularly so when the craft is unusual or disappearing. A video came our way of just such a thing, and it’s of a craft so rare that it’s possible few of us will have considered it. We’re used to buying tyres for our motor vehicles that come pre-made in a mould for the size of our wheels, but how many of us have considered where the origins of the rubber tyre lie? How did a 19th-century horse-drawn buggy get its tyres? [EngelsCoachShop] take us through the process, putting rubber on a set of wooden carriage wheels.

These wheels would originally have had iron rims, that must have provided a jarring ride on cobbled roads of the day. English coach-builders of the mid 19th century were the first to fit solid rubber tyres, and it’s this type of tyre that’s being fitted in the video. Instead of the rubber ring we might expect the tyre is cut from a length of vulcanised rubber extrusion with a significant overlap, then a pair of high-tensile wires are fed through holes in the extrusion. The impressive part is the jig for creating the tyre, in which the rubber is compressed to a tight fit on the wheel before the wires are cut and their ends brazed together. Once the wheel is released from the jig  the compressed tyre expands to the point at which its ends meet, making a perfect circular tyre held tightly on the rim. Few of us will ever see this for real, but we’re privileged to see it on the screen.

We may not deal with wooden wheels very often, but this isn’t the first set we’ve seen.

Continue reading “Rubber Tyres Before There Were Tyres” →

Modern Features In Classic Radio

December 7, 2021 by 53 Comments

As consumer electronics companies chase profits on tighter and tighter margins, it seems like quality is continually harder to find for most average consumer-grade products. Luckily, we don’t have to hunt through product reviews to find well-built merchandise since we have the benefit of survivorship bias to help us identify quality products from the past that have already withstood the test of time. [Tom] has forever been fond of this particular Sony TV/radio combo from the ’70s so he finally found one and set about modernizing it in a few key ways.

Among the modifications to this 1978 Sony FX-300 include the addition of a modern color display, Bluetooth, an upgraded FM radio, and a microphone. At the center of all of this new hardware is a Teensy 4 which [Tom] has found to be quite powerful and has enough capabilities to process the audio that’s being played in order to make visual representations of the sound on the screen. He also implemented a bitcrusher filter and integrated it into the controls on the original hardware. He’s using an optimized version of this library to cram all of that processing ability into such a small chip, and the integration of all this new hardware is so polished that it looks like it could be an original Sony stereo from the modern era.

While some may complain about restomod-type builds like this, we don’t really see any need to be arbitrarily or absolutely faithful to bygone eras even if the original hardware was working properly in the first place. What works is taking the proven technology of the past and augmenting it with modern features to enjoy the best of both worlds. Much like this hi-fi stereo which blends the styles and technology of the 90s with that of the 60s in an equally impressive way.

Assistive Tech And Video Games

December 7, 2021 by 6 Comments

Assistive technologies have a pretty big presence here on Hackaday, and this hack is nothing short of interesting. [kerchoo_22] is working on a hands-free video game controller as a final project for her engineering class and we think it’s worth sharing.

The basic premise of the circuit is pretty simple. She DIY’d a few contact switches using conductive plates made of cardboard, duct tape, and aluminum foil. The output of the switch is read by analog input pins on an Arduino Leonardo. When the switches are off, the analog input pins are pulled HIGH using 1 MegaOhm resistors. But when the user hits their head on one of the four conductive pads, the switch is engaged, and the analog input pins are shorted to ground.

The Arduino Leonardo, having a native USB port, is able to directly emulate a keyboard. Each conductive pad is mapped to a different key press corresponding to different functions within the game. Left, right, shoot, etc. And there you have it, gameplay without using hands or a controller!

Now, it seems as though [kerchoo_22] put an appropriate amount of cushion on the head pads, so there probably isn’t much danger of a concussion. Either way, you can never be too careful.

Complete Hobo Stove Cooking System Could Get You Through The Apocalypse

December 7, 2021 by 70 Comments

Let’s face it, times are hard, and winter is imminent in the northern hemisphere. No matter how much you have to your name, there’s nothing like a cup of hot tea or a warm meal on a cold day. So if you need a snow day activity, consider preparing for whatever may come to pass by building yourself a complete hobo stove system out of empty cans.

[ElectroIntellect]’s stove consists of a 20oz can turned upside down with several holes made in the bottom for heat to rise. The smaller cans are used for cooking pots, and the smallest as a cup. The stove itself is meant to run on flaming twigs stuffed into the base, or a couple of tealight candles if you can only find green wood around.

This comprehensive guide covers everything from building the system to packing it up safely and taking it out to cook in the concrete wilderness. As a special bonus, [ElectroIntellect] brews up some hobo coffee on the stove using an old (clean) sock, and prepares a can of chili in under an hour with candle power.

Too much hardware for you? You can make a disposable rocket stove out of wood.

Marble-elevator dot-matric display

Simple Design Elevates This Mechanical Dot Matrix Display

December 7, 2021 by 11 Comments

Don’t get us wrong — we love unique displays as much as anyone. But sometimes we stumble across one that’s so unique that we lack the basic vocabulary to describe it. Such is the case with this marble-raising dot-matrix alphanumeric display. But it’s pretty cool, so we’ll give it a shot.

The core — literally — of [Shinsaku Hiura]’s design is a 3D-printed cylinder with a spiral groove in its outside circumference. The cylinder rotates inside a cage with vertical bars; the bars and the grooves are sized to trap 6-mm AirSoft BBs, which are fed into the groove by a port in the stationary base of the display. BBs are fed into the groove at the right position to form characters, which move upwards as the cylinder rotates. Just watch the video below — it explains it far better than words can.

The clever bit is how the BBs are fed into the groove. Rather than have a separate mechanism to gate the feed port, there’s a backlash mechanism that opens the port when the motor powering the drum runs in reverse for a bit. It’s a clever use of cams to get the job done without adding an extra servo, which sort of reminds us of the design parsimony exhibited in his one-servo seven-segment display.

It’s not clear that this would be a very practical display, but that doesn’t stop it from being cool. Although, [Shinsaku Hiura] just released a follow-up video showing a bigger version of this used to display upcoming events from Google Calendar, so perhaps we’re wrong. Continue reading “Simple Design Elevates This Mechanical Dot Matrix Display” →