Author: Jenny List

3035 Articles

You’ve Got The Portable Radio, Now What About The Antenna?

July 28, 2024 by 10 Comments

There’s an old saying in the amateur radio community that when it comes to antennas all you need is a piece of wet string. This may be a little fanciful, but it’s certainly true that an effective antenna can be made with surprisingly little in the way of conductor. It’s something [Evan Pratten VZ3ZZA] demonstrates amply with a description of the antenna he took camping in a Canadian provincial park.

Most of us would try some form of dipole on our adventures, but the antenna he’s using caught our eye as it’s described as an end-fed half-wave, but it has both a half-wave and quarter-wave element. Made from speaker cable or in this case thin mains cable for lamps, it’s obviously far from a perfect match and requires an ATU, but it generates an impressive array of FT4 contacts on a pretty meagre power level. We particularly like his in-plain-sight test run in the parking lot of a supermarket.

We frequently talk about the diversity of pursuits in amateur radio aside from that of the chequebook ham, and this project shows one of those. The world of QRP, operating at extreme low power, is not expensive to enter and can be extremely rewarding.

An RC Tracked Robot, Without The Pain

July 28, 2024 by 13 Comments

Small robots can be found at all levels from STEM toys for kids all the way through to complex hacker projects. Somewhere along that line between easy enough for anyone to build and interesting enough for hackers lies the PlayCar, from [ComfySpace]. It’s a small build-it-yourself tracked robot that’s controlled from your smartphone via an app.

At the PlayCar’s heart is a Raspberry Pi Zero 2W, and surrounding it are a set of inexpensive off the shelf modules for power and motor control. The juice meanwhile comes from a set of AA batteries, and the motors are geared DC units. Having acquired all the components, the 3D printable parts can then be downloaded from Printables, and the ComfySpace app can be downloaded for either Apple or Android platforms.

It’s clear that ComfySpace is a start-up targeting the education sector, and we wish them every success. The approach of making an open platform is one we like, as it has the potential to create a community feeding back designs and add-ons rather than remaining proprietary. You can take a  look at the video below the break for more information.

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A Demo Party On A Chip

July 28, 2024 by 5 Comments

The demoscene has provided our community with its artistic outlet since the first computers which could handle graphics, and has stayed at the forefront of technology all the way. For all that though, there’s a frontier it hasn’t yet entirely conquered, which exists in the realm of silicon. To address this cones the ever awesome Tiny Tapeout, who are bringing their ASIC-for-the-masses scheme to the world of demos with an ASIC demo competition.

With a closing date of 6th of September, all accepted entrants get a free Tiny Tapeout tile for their entry. Entries are limited to two tiles or less. with VGA and audio outputs via a specified PMOD pinout. There are a variety of categories including the expected best sound and best graphics, but among them we’re most interested by the mixed signal one that includes analogue circuitry.

Tiny Tapeout has been a particularly exciting project over the last couple of years, truly breaking new ground for the hardware hacker world. Since they’ve just recently been able to start doing some analog design on the chips, we’re excited to see what people come up with for this competition, and we hope it will provide significant advancement to the art. In the best tradition of the demo scene, they’ve even made an intro for the competition, which you can see below the break.

Want to know what all the fuss is about? Start here!

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Vintage Ribbon Cable Repair Saves Poqet PC

July 26, 2024 by 19 Comments

It sometimes seems as though computing power in your pocket is a relatively new phenomenon, but in fact there have been ultraportable computers since the 8-bit era. They started to become useful around the end of the 1980s though as enterprising manufacturers started cramming full-fat PC XTs into pocket form factors. Of these the one to own was the Poqet PC, a slim clamshell design that would run for ages on a pair of AA cells . If you have one today you’d be lucky if its display ribbon cable is without faults though, and [Robert’s Retro] is here with a fix previously thought impossible.

A large proportion of the video below the break is devoted to dismantling the unit, no easy task. The cable once exposed is found to have delaminated completely, and he takes us through the delicate task of attaching a modern equivalent. We particularly like the way in which the cable’s own springiness is used to retract it. The result has a white cable rather than the original black, but that’s a small price to pay for a machine that works rather than a broken paperweight.

If early pocket computing is your thing, it’s a subject we’ve covered before.

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Your QuickTake Camera And Your Modern PC

July 26, 2024 by 10 Comments

An object of desire back in the mid-1990s might have been Apple’s QuickTake camera. In a form factor not unlike a monocular it packed a 640×480 digital camera, the images from which could be downloaded to a computer via a serial cable. A quarter century later it’s a great retro camera for the enthusiast, but both the serial ports and the operating systems needed to run its software have passed into history. Time for the junk pile? Not at all, for [Crazylegstoo] has produced a new piece of software for 2024 that works for both QuickTake 100 and 150 cameras with USB serial ports on modern operating systems.

Called JQuickTake, it’s a Java app which has the advantage of building on that early Java promise of running cross platform so can be had for Mac or Windows. It allows retrieval of both metadata and images from the camera, but sadly it doesn’t display any of the images. It also doesn’t work with the QuickTake 200. Happily though, there are instructions for building a serial cable, and suggestions for how to deal with the proprietary QTK image format.

Meanwhile if you lack a PC or Mac all is not lost. You can also use these cameras with an Apple II.

Header image: Hannes Grobe, CC BY-SA 4.0.

Can Cats Solve Puzzles?

July 26, 2024 by 29 Comments

Cats, to those of us who appreciate their company, are fascinating creatures, with their infinite curiosity and playfulness. [Makers Muse] has a pair of half-grown-up kittens, and set out to provide them with a plaything far better than those the market could offer. The result is the Snak Attak, a gravity puzzle maze that delivers kibble for the cat prepared to puzzle it out.

The point of this exercise isn’t to give kibble but to provide the optimum play experience for a pair of younger cats. The premise is that kibble is held back by a set of wooden pegs each with a temptingly dangly string, and they should after some investigation be able to pull the pegs out and release it. What’s interesting is how the two different cats approach the problem, while one pulls the out as expected, the other pushes them from the back of the device.

The conclusion is that the two cats can indeed solve puzzles, and gain hours of play from the device. An updated version was produced with a few more challenges, and as you can see in the video below the break, it’s captivated their attention. It’s not the first cat toy we’ve brought you by any means, this robotic mouse springs to mind, but it’s certainly upped the ante on feline entertainment.

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A Lenticular Clock Spells Out The Hours

July 24, 2024 by 1 Comment

So many are the clock projects which cross the Hackaday threshold, that it’s very rare indeed to see something that hasn’t already been done. We think we’ve not seen a lenticular clock before though, and we’re thus impressed by this one produced by [Moritz Sivers].

You may well be familiar with lenticular images from toys and novelties, an animation is sliced into lines and placed behind an array of multi-faceted linear lenses. It gives the effect of movement as from different viewing angles a different frame of the animation is perceived. In this clock the animation is replaced by the clock digits, and by rotating the whole with a servo driven by an ESP8266 microcontroller it can display different digits to the viewer. The write-up and the video below are of value both for the clock itself and the description of how these animations are produced. The clock itself doesn’t sacrifice usability for all its novelty, and we can see this technique might find a place in other projects requiring custom displays.

The lenticular lenses used here are off the shelf, but if you are of an adventurous mind, you could try printing some of your own.

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