Hamvention 2022: The Reunion Begins Today

May 20, 2022 by Kristina Panos 7 Comments

Calling all hams! Hamvention 2022 is underway and runs through the weekend at the Greene County Fair and Expo Center in Xenia, Ohio. It’s been three long years since Hamvention took place in person, and this year marks the 70th reunion of what has got to be the largest hamfest in the Midwest. If you’re in the area, you don’t want to miss it. You will need a ticket, though, and here are a few places you pick one up.

Indoors, you’ll find six buildings full of commercial vendors. But outside is where the real fun takes place — the flea market. What treasures will you uncover? There’s only one way to find out.

If you want to get into ham radio, there’s no place like a ham fest to kick off your journey. And if you’ve been poring over the ARRL handbook, you’re in luck, because they’re proctoring ham exams for free at the church across the street on Friday and Saturday.

Can’t make it out for whatever reason, but live close to the fairgrounds? Want to get in the mood on your way there? Tune to 1620AM within a five-ish mile radius to hear weather, traffic, and parking info, plus interviews and other assorted radio fun. If you live nowhere near Ohio, don’t despair — they are livestreaming it on YouTube.

[Note: the Hara Arena, pictured in our awesome Joe Kim artwork, is the old home of Hamvention, and was demolished in 2016. Better head off to the Greene County Fairgrounds instead.]

When Hams Helped Polar Researchers Come In From The Cold

May 17, 2022 by Al Williams 23 Comments

We always enjoy [The History Guy] videos, although many of them aren’t much about technology. However, when he does cover tech topics, he does it well and his recent video on how ham radio operators assisted in operation Deep Freeze is a great example. You can watch the video, below.

The backdrop is the International Geophysical Year (IGY) where many nations cooperated to learn more about the Earth. In particular, from 1957 to 1958 there was a push to learn more about the last unexplored corner of our planet: Antarctica. Several of the permanent bases on the icy continent today were started during the IGY.

It’s hard for modern audiences to appreciate what the state of personal communication was in 1957. There were no cell phones and if you are thinking about satellites, don’t forget that Sputnik didn’t launch until late 1957, so that wasn’t going to happen, either.

Operation Deep Freeze had ten U. S. Navy vessels that brought scientists, planes, and Seabees (slang for members of the Naval Construction Batallion) — about 1,800 people in all over several years culminating in the IGY. Of course, the Navy had radio capabilities, but it wasn’t like the Navy to let you just call home to chat. Not to mention, a little more than 100 people were left for each winter and the Navy ships went home. That’s where ham radio operators came in.

Hams would do what is called a phone patch for the people stationed in Antarctica. Some hams also send radiograms to and from the crew’s families. One teen named Jules was especially dedicated to making connections to Antarctica. We can’t verify it, but one commenter says that Jules was so instrumental in connecting his father in Antarctica to his fiancee that when his parents married, Jules was their best man.

Jules and his brother dedicated themselves to keeping a morale pipeline from New Jersey to the frozen stations. He figures prominently in recollections of many of the written accounts from people who wintered at the nascent bases. Apparently, many of the men even traveled to New Jersey later to visit Jules. What happened to him? Watch the end of the video and you’ll find out.

While being a ham today doesn’t offer this kind of excitement, hams still contribute to science. Want to get in on the action? [Dan Maloney] can tell you how to get started on the cheap.

Continue reading “When Hams Helped Polar Researchers Come In From The Cold” →

LoRa-Powered Birdhouses Enable Wireless Networking When The Internet’s Down

April 9, 2022 by Robin Kearey 25 Comments

One of the design requirements for the networks that evolved into the Internet was the ability to keep functioning, even if some nodes or links were disabled or destroyed in war. The packet-switched architecture that still powers today’s Internet is a direct result of that: if one link stops functioning, information is automatically re-routed towards its intended destination. However, with tech giants occupying increasingly large parts of the global internet, an outage at one of them might still cause major disruption. In addition, a large-scale power interruption can disable large parts of the network if multiple nodes are connected to the same grid.

Six pieces of wood, with a hammer next to them — Just six pieces of wood make up the birdhouse.

Enter the LoRa Birdhouse project by the Wellesley Amateur Radio Society that solves those two problems, although admittedly at a very small scale. Developed by amateur radio operators in eastern Massachusetts, it’s basically a general-purpose LoRa-based packet-switching network. As it’s based on open-source hardware and commonly available components, its design allows anyone to set up a similar network in their own area.

The network is built from nodes that can receive messages from their neighbors and pass them on towards their final destination. Each node contains a Semtech SX1276 transceiver operating in the 902-928 MHz band, which gets its data from an ESP32 microcontroller. The nodes are placed in strategic locations outside and are powered by solar panels to reduce their ecological footprint, as well as to ensure resilience in case of a power outage. To make the whole project even more eco-friendly, each node is built into a birdhouse that provides shelter to small birds.

Users can access the network through modified network nodes that can be hooked up to a PC using a USB cable. Currently, a serial terminal program is the only way to interact with the network, although a more user-friendly interface is being planned. FCC rules also require all users (except any avian residents) to be licensed amateur radio operators, and all traffic to remain unencrypted. Tests have shown that one kilometer between nodes can work in the right conditions, enabling the deployment of networks across reasonably large areas.

While the Birdhouse Network might not be a plug-and-play internet replacement in case of a nuclear apocalypse, it does provide an excellent system to experiment with packet-switching wireless network technology. We’ve seen similar LoRa-based network initiatives like Qmesh, Cellsol and Meshtastic, all of which provide some way to communicate wirelessly without requiring any centralized hardware.

Wind-Up Tape Measure Transformed Into Portable Ham Antenna

March 30, 2022 by Dan Maloney 20 Comments

If there’s one thing that amateur radio operators are good at, it’s turning just about anything into an antenna. And hams have a long history of portable operations, too, where they drag a (sometimes) minimalist setup of gear into the woods and set up shop to bag some contacts. Getting the two together, as with this field-portable antenna made from a tape measure, is a double win in any ham’s book.

For [Paul (OM0ET)], this build seems motivated mainly by the portability aspect, and less by the “will it antenna?” challenge. In keeping with that, he chose a 50-meter steel tape measure as the basis of the build. This isn’t one of those retractable tape measures, mind you — just a long strip of flexible metal on a wind-up spool in a plastic case. His idea was to use the tape as the radiator for an end-fed halfwave, or EFHW, antenna, a multiband design that’s a popular option for hams operating from the 80-m band down to the 10-m band. EFHW antennas require an impedance-matching transformer, a miniature version of which [Paul] built and tucked within the tape measure case, along with a BNC connector to connect to the radio and a flying lead to connect to the tape.

Since a half-wave antenna is half the length of the target wavelength, [Paul] cut off the last ten meters of the tape to save a little weight. He also scratched off the coating on the tape at about the 40-meter mark, to make good contact with the alligator clip on the flying lead. The first video below details the build, while the second video shows the antenna under test in the field, where it met all of the initial criteria of portability and ease of deployment.

Continue reading “Wind-Up Tape Measure Transformed Into Portable Ham Antenna” →

Homemade Panadapter Brings Waterfall To Old Radio

February 20, 2022 by Adam Zeloof 15 Comments

Ham radio operators can be pretty selective about their gear. Some are old-school tube purists who would never think of touching a rig containing transistors, and others are perfectly happy with the small Software Defined Radio (SDR) hooked up to their PC. The vast majority, though, of us are somewhere in between — we appreciate the classic look and feel of vintage radios as well as the convenience of modern ones. Better yet, some of us even like to combine the two by adding a few modern bells and whistles to our favorite “boat anchor.”

[Scott Baker] is one such Ham. He’s only had his license for a few months now and has already jumped into some great projects, including adding a panadapter to an old Drake R-4B Receiver. What’s a panadapter, you may ask? As [Scott] explains in his excellent writeup and video, a panadapter is a circuit that grabs a wideband signal from a radio receiver that typically has a narrowband output. The idea is that rather than just listen to somebody’s 4kHz-wide transmission in the 40m band, you can listen to a huge swath of the spectrum, covering potentially hundreds of transmissions, all at the same time.

Well, you can’t actually listen to that many transmissions at once — that would be a garbed mess. What you can do with that ultrawide signal, however, is look at it. If you take an FFT of the signal to put it in the frequency domain (by using a spectrum analyzer, or in [Scott]’s case, an SDR), you can see all sorts of different signals up and down the spectrum. This makes it a heck of a lot easier to find something to listen to — rather than spinning the dial for hours, hoping to come across a transmission, you can just see where all of the interesting signals are.

This isn’t the first (or even the twentieth) time that [Scott]’s work has graced our pages, so make sure to check some of his other incredible projects in our archives!

Continue reading “Homemade Panadapter Brings Waterfall To Old Radio” →

Directional Antenna 3-Way

January 21, 2022 by Al Williams 10 Comments

If you read old antenna books, you’ll probably see the idea of phased vertical antennas. These use certain lengths of coax to control the phase of a signal going to three verticals in a triangular configuration. Depending on the phasing, you can cause the array of antennas to be directional in one of three directions. [DX Commander] designed a very modern version of this antenna and shows the theory behind it in a recent video that you can see below.

It seems another ham built the antenna and a control box for it which he’s sent to [DX Commander] although he hasn’t set it up yet to create an 80 meter directional antenna. We’ll be interested in seeing how it works in practice.

Continue reading “Directional Antenna 3-Way” →

Ham Antenna Fits Almost Anywhere

January 6, 2022 by Al Williams 35 Comments

[G3OJV] knows the pain of trying to operate a ham radio transmitter on a small lot. His recent video shows how to put up a workable basic HF antenna in a small backyard. The center of the system is a 49:1 unun. An unun is like a balun, but while a balun goes from balanced line to an unbalanced antenna, the unun has both sides unbalanced. You can see his explanation in the video below.

The tiny hand-size box costs well under $40 or $50 and covers the whole HF band at up to 200 W. The video shows the inside of the box which, as you’d expect, is a toroid with a few turns of wire.

Continue reading “Ham Antenna Fits Almost Anywhere” →