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

December 8, 2021 by Ryan Flowers 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” →

Moon Bouncing And Radar Imaging With LoRa

December 3, 2021 by Ryan Flowers 17 Comments

The LoRa radio protocol is well known to hardware hackers because of its Long Range (hence the name) but also its extremely low power use, making it a go-to for battery powered devices with tiny antennae. But what if the power wasn’t low, and the antenna not tiny? You might just bounce a LoRa message off the moon. But that’s not all.

The team that pulled off the LoRa Moonbounce consisted of folks from the European Space Agency, Lacuna Space, and the CA Muller Radio Astronomy Station Foundation which operates the Dwingeloo Radio Telescope. The Dwingeloo Radio Telescope is no stranger to Amateur Radio experiments, but this one was unique.

LoRa Moonbounce plotted for doppler shift by frequency — A radar image of the moon generated from LoRa Moonbounce

Operating in the 70 cm Amateur Radio band (430 MHz) meant that the LoRa signal was not limited to the low power signals allowed in the ISM bands. The team amplified the signal to 350 Watts, and then used the radio telescope’s 25 Meter dish to direct the transmission toward the moon.

The result? Not only were they able to receive the reflected transmission using the same transceiver they modulated it with — an off the shelf IOT LoRa radio — but they also recorded the transmission with an SDR. By plotting frequency and doppler delay, the LoRa transmission was able to be used to get a radar image of the moon- a great dual purpose use that is noteworthy in and of itself.

LoRa is a versatile technology, and can even be used for tracking your High Altitude Balloon that’s returned to Terra Firma.

IPod, Therefore I Am: Looking Back At An Original IPod Prototype

December 3, 2021 by Ryan Flowers 17 Comments

Have you ever wondered what consumer electronics look like when they’re in the ugly prototype stages? So have we. And thanks to [Cabel] of at Panic.com, we have a rare glimpse at a prototype first generation Apple iPod.

In the days before you could just stream your favorite music directly from your phone and into your Bluetooth speaker, pods, or car, there was the Sony Walkman and various portable tape players. Then there were portable CD players. As MP3’s became a popular format, CD players that could play MP3’s on home made CD’s were popular. Some portable digital media players came to market in the mid 1990’s. But in October of 2001, the scene changed forever when Apple unveiled the first generation iPod.

Of course, the iPod didn’t start out being so svelte, shiny, and downright cool. This engineering prototype has been hiding in [Cabel]’s closet for almost 20 years and they’ve just now decided to share with us its hilariously oversized case, JTAG port, and square pushbuttons that look like they came from a local electronics supply house. As [Cabel] brings out in the excellent writeup, the hardware itself is very close to production level, and the date on the prototype is very near the actual product launch.

Of course prototyping is an essential part of building any product, production or otherwise. Having a gander at such pre-production devices like this, or these off-ear speaker prototype for Valve’s VR headset reminds us just how important even the ugliest prototypes can be.

Have you got any pre-production nuggets to share with the world? Be sure to let us know by dropping a note in the Tip Line, and thanks to [jp] who sent this one in!

Homebrew 16 Bit Computer Reinvents All The Wheels

December 3, 2021 by Ryan Flowers 23 Comments

Building your own computer has many possible paths. One can fabricate their own Z80 or MOS 6502 computers and then run a period correct OS. Or a person could start from scratch as [James Stanley] did. [James] has invented a completely unique computer and CPU he calls SCAMP. SCAMP runs a custom OS called SCAMP/os which you can check out in the video below the break.

[James] describes the CPU and computer as purposefully primitive. Built out of discrete 74xx series logic chips, it runs at a fast-enough-for-homebrew 1 MHz. Plus, it has a lot of blinking lights that can’t help but remind us of the original Imsai 8080. But instead of a panel of switches for programming, the SCAMP/os boots to a shell, which is presented through a serial terminal. Programs are written in a bespoke language with its own compiler. The OS is described as a having a Unix-like feel with CP/M-like functionality. That’s quite a combination!

What we love most about the build, other than its clean looks and blinkenlights, is the amount of work that [James] has put into documenting the build both on his blog and on Github, where the source code and design is available. There’s also an open invitation for contributors to help advance the project. We’re sure he’ll get there, one bit at a time.

While [James] is using a Compact Flash card for storage currently we can’t help but wonder if a Cassette Tape storage system might be a worthwhile future upgrade.

Continue reading “Homebrew 16 Bit Computer Reinvents All The Wheels” →

Asus Motherboard gets CPU Upgrade Past its Specs

Clever Motherboard Hack Brings Late 90’s Motherboard Into The Early 2000’s

December 2, 2021 by Ryan Flowers 32 Comments

Some people look at specifications as a requirement, and others look at them as a challenge. You’re reading this on Hackaday, so you know where [Necroware] falls. In the video below the break, you’ll see how he takes a common mid-to-late 90’s motherboard and takes it well past its spec sheet.

A pull up resistor enables faster clock multipliers — [Necroware] does what all soldering iron ads think people do with soldering irons

Having already started with replacing the Real Time Clock with his own creation, [Necroware] looked for other opportunities to make the Asus P/I-P55TP4XEG more capable than Asus did. And, he succeeded. Realizing that the motherboard has the ability to have an external voltage regulator board, [Necroware] made one so that the Socket 7 board could supply more than a single voltage to the CPU- the very thing keeping him from upgrading from a Pentium 133 to a Pentium MMX 200.

While the upgrade was partially successful, a deep dive into the Socket 7 and Super Socket 7 documentation helped him realize the need for a pullup resistor on a strategic clocking pin. Then, [Necroware] went full Turbo and smashed this author’s favorite single core CPU of all time into the socket: the AMD K6-2 450, a CPU well beyond the original capabilities of the board.

It really goes to show that, of course, It’s All About The Pentiums. Thanks to [BaldPower] for the doing the needful and dropping this great hack into the Tip Line!

Continue reading “Clever Motherboard Hack Brings Late 90’s Motherboard Into The Early 2000’s” →

Low Buck PVC ROV IS Definitely A MVP

December 2, 2021 by Ryan Flowers 8 Comments

Do you have a hundred bucks and some time to kill? [Peter Sripol] invites you to come along with him and build a remotely operated submarine with only the most basic, easily accessible parts, as you can see in the video below the break.

Using nothing more than PVC pipe, an Ethernet cable, and a very basic electrical system, [Peter] has built a real MVP of a submarine. No, not Most Valuable Player; Minimum Viable Product. You see, there’s not a microcontroller, motor controller, sensor, or MOSFET to be found except for that which might reside inside the knock-off GoPro style camera which is encased in a candle wax sealed enclosure.

Instead, simple brushed motors live right out in the open water. Single pole double throw switches are connected to 100 feet of Ethernet cable and control the relays powering the motors. The camera signal is brought back to the controller through the same cable. Simple is the key to the build, and we have to admit that for all of its Minimum Viability, the little ROV has a lot going for it. [Peter] even manages to use the little craft to find and make possible the retrieval of a crustacean encrusted shopping cart from a saltwater canal. Not bad, little rover, not bad.

Also noteworthy is that the video below has its own PVC ROV Sea Shanty, which is something you just don’t hear every day.

Underwater ROV builds are the sort of thing almost every hacker thinks about doing at least once, and some hackers even include Lego, magnets, and balloons in their builds! Continue reading “Low Buck PVC ROV IS Definitely A MVP” →

The supersonic trebuchet being modeled in software

Supersonic Projectile Exceeds Engineers Dreams: The Supersonic Trebuchet

December 1, 2021 by Ryan Flowers 62 Comments

Have you ever sat down and thought “I wonder if a trebuchet could launch a projectile at supersonic speeds?” Neither have we. That’s what separates [David Eade] from the rest of us. He didn’t just ask the question, he answered it! And he documented the entire build in a YouTube video which you can see below the break.

The trebuchet is a type of catapult that was popular for use as a siege engine before gunpowder became a thing. Trebuchets use a long arm to throw projectiles farther than traditional catapults. The focus has typically been on increasing throwing distance for the size of the projectile, or vice versa. But of course you’re here to read about the other thing that trebuchets can be used for: speed.

How fast is fast? How about a whip-cracking, sonic-booming speed in excess of 450 meters per second! How’d he do it? Mostly wood and rubber with some metal bits thrown in for safety’s sake. [David]’s video explains in full all of the engineering that went into his trebuchet, and it’s a lot less than you’d think. There’s a very satisfying montage of full power trebuchet launches that make it audibly clear that the projectile being thrown is going well past the speed of sound, with a report quite similar to that of a small rifle.

[David]’s impressive project and presentation makes it clear that all one has to do to build a supersonic trebuchet is to try. Just be careful, and watch where you shoot that thing before you put somebody’s eye out, ok?

Speaking of things that can go unexpectedly fast, check out these unpowered RC gliders that approach the speed of sound just feet off the ground. And thanks to [Keith] for the awesome Tip!

Continue reading “Supersonic Projectile Exceeds Engineers Dreams: The Supersonic Trebuchet” →