Making a multi-band amateur radio transceiver has always been a somewhat challenging project, and making one that also supported different modes would for many years have been of almost impossible complexity best reserved for expensive commercial projects. [Bob W7PUA] has tackled both in the form of a portable 10-band multi-mode unit, and we can honestly say he’s done a very good job indeed.

As you might expect in 2025 it’s a software defined radio (SDR), but to show how powerful the silicon available today is, it’s all implemented on a microcontroller. There’s a Teensy 4 with an audio codec board that does all the signal processing heavy lifting, and an RF board that takes care of the I/Q mixing and the analogue stuff.

Band switching is handled using a technique from the past; interchangeable plug-in coil and filter units, that do an effective job. The result is a modestly-powered but extremely portable rig that doesn’t look to have broken the bank, and since the write-up goes into detail on the software side we hope it might inform other SDR projects too. We might have gone for old-school embossed Dymo labels on that brushed aluminium case just for retro appeal, but we can’t fault it.

It’s not the first time we’ve looked at a small multi-band SDR here, but we think this one ups the game somewhat.

Thanks [Pete] for the tip!

We hear a lot about how ham radio isn’t what it used to be. But what was it like? Well, the ARRL’s film “The Ham’s Wide World” shows a snapshot of the radio hobby in the 1960s, which you can watch below. The narrator is no other than the famous ham [Arthur Godfrey] and also features fellow ham and U.S. Senator [Barry Goldwater]. But the real stars of the show are all the vintage gear: Heathkit, Swan, and a very oddly placed Drake.

The story starts with a QSO between a Mexican grocer and a U.S. teenager. But it quickly turns to a Field Day event. Since the film is from the ARRL, the terminology and explanations make sense. You’ll hear real Morse code and accurate ham lingo.

Is ham radio really different today? Truthfully, not so much. Hams still talk to people worldwide and set up mobile and portable stations. Sure, hams use different modes in addition to voice. There are many options that weren’t available to the hams of the 1960s, but many people still work with old gear and older modes and enjoy newer things like microwave communications, satellite work, and even merging radio with the Internet.

In a case of history repeating itself, there is an example of hams providing communications during a California wildfire. Hams still provide emergency communication in quite a few situations. It is hard to remember that before the advent of cell phones, a significant thing hams like [Barry Goldwater] did was to connect servicemen and scientists overseas to their families via a “phone patch.” Not much of that is happening today, of course, but you can still listen in to ham radio contacts that are partially over the Internet right in your web browser.

When the first artificial satellite, Sputnik, was put into orbit around Earth, anyone in the path of the satellite could receive the beeps transmitted by the satellite provided they had some simple radio equipment. Of course, there was no two-way communication with this satellite, and it only lasted a few weeks before its batteries died. Here in the future, though, there are many more satellites in orbit and a few are specifically meant for ham radio operators. And, like the ’50s, it doesn’t take too much specialized equipment to communicate with them, although now that communication can be two-way.

The first step in this guide by [W2PAK] is to know where these satellites are in the sky. The simplest way to do that is to use a smartphone app called GoSatWatch and, when configured for a specific location, shows the satellites currently overhead. After that it’s time to break out the radio gear, which can be surprisingly inexpensive. A dual-band handheld is required since satellite uplink and downlink can be on different bands, and the antenna can be made from simple parts as well as [W2PAK] demonstrates in a separate video. Combined, this can easily be done for less than $100. [W2PAK] also goes over the proper format and etiquette for a satellite contact as well, so a new operator can pick it up quickly.

Using satellites as repeaters opens up a lot of capabilities when compared to terrestrial communications. Especially for operators with entry-level licenses who are restricted to mostly VHF and UHF, it adds a challenge as well as significantly increased range compared to ground-based repeaters and line-of-sight communications. There are plenty of activities around satellites that don’t require a license at all, too, like this project which downloads weather imagery from weather satellites.

The moon is a popular target for ham radio operators to bounce signals since it’s fairly large and follows a predictable path. There are some downsides, though; it’s not always visible from the same point on Earth and is a relatively long way away. Thinking they could trade some distance for size, an amateur radio group from the Netherlands was recently able to use a radio telescope pointed at a geostationary satellite to reflect a signal back down to Earth, using this man-made satellite to complete the path instead of the more common natural one.

While there are plenty of satellites in orbit meant for amateur radio communication (including the International Space Station, although it occasionally does other things too), these all have built-in radio transmitters or repeaters specifically meant for re-transmitting received signals. They’re also generally not in geostationary orbit. So, with a retired radio telescope with a 20-meter dish aimed directly at one of the ones already there, they sent out a signal which bounced off of the physical body of the satellite and then back down where it was received by a station in Switzerland. Of course, the path loss here is fairly extreme as well since the satellite is small compared to the moon and geostationary orbit is a significant distance away, so they used the Q65 mode in WSJT-X which is specifically designed for recovering weak signals.

Don’t break out the tape measure Yagi antenna to try this yourself just yet, though. This path is not quite as reliable as Earth-Moon-Earth for a few reasons the group is not quite sure about yet. Not every satellite they aimed their dish at worked, although they theorize that this might be because of different shapes and sizes of the satellites or that the solar panels were not pointing the correct direction. But they were able to make a few contacts using this method nonetheless, a remarkable achievement they can add to their list which includes receiving a signal from one of the Voyager spacecraft.

Full disclosure: ham radio isn’t for everyone, and there are many different facets to it. What appeals to one person might bore another to death. One area of ham radio that has changed a lot in the last few years is more or less local and typically mobile operation on VHF or UHF. Not long ago, hams used HTs (walky-talkies or handi-talkies) or mobile radios via repeaters to talk to each other and — the golden prize back then — make phone calls from their cars. Cell phones have made that much less interesting, but there is still an active community of operators talking on repeaters. However, the traffic has gone digital, the Internet is involved, and people with inexpensive, low-powered radios can talk to each other across the globe. This is nothing new, of course. However, having digital services means that operators with special interests can congregate in what amounts to radio chat rooms organized by region or topic.

There’s a long history of people listening to ham radio conversations with shortwave radios, SDRs, and scanners. But with so much activity now carried on the Internet, you can listen in using nothing more than your web browser or a phone app. I’ll show you how. If you get interested enough, it is easy enough to get your license. You don’t need any Morse code anymore, and a simple Technician class license in the United States is all you need to get going.

A Quick DMR Primer

There are several digital ham networks around and like real networks, you can have different physical transport layers and then build on top of that. For the purposes of this post, I’m going to focus on DMR (digital mobile radio) on the Brandmeister network which is very large and popular ham network. You won’t need a license nor will you need to sign up for anything as long as you are content to just listen.

Here’s how it works: Brandmeister operates a large number of servers worldwide that communicate with each other and provide calling services, including group calls. So, if we set up a Hackaday talk group (fictitious, by the way) on group 1337, interested people could connect to that talk group and have a conversation.

Since we are just going to listen, I’m going to skip some of the details, but the trick is how people get to talk to these networks. In general, there are three ways. The classic way is to use a digital radio to talk to a repeater that is connected to the network. The repeater may have one or more talk groups on all the time, or you might request access to one.

However, another way to connect your radio to a “hotspot” connected to the Internet. That is, more or less, a special form of repeater that is very low power, and you have complete control over it compared to a repeater on some faraway hill. However, if you don’t mind operating using just a computer, you don’t need a radio at all. You simply talk directly to the nearest server, and you are on the network. Some of your audio will go to other computers, and it may go over the airwaves via someone else’s hotspot or repeater.

Talk Groups

The Brandmeister website has a lot of info and you don’t need to be logged in to see it. Head over to their site and you’ll see a lot of info including a network map and statistics about repeaters and hotspots. You can get an idea of who has been talking lately by clicking Last Heard link. While this is interesting, it isn’t as interesting as you’d think, because you really want to focus on talk groups, not individual users.

To see a list of all the talk groups on the system, you can click Information and then Talkgroups. You can filter the list and you can also download the dataset in different formats if you want to browse it in a different format.

There are three buttons on each row of the database. The LH button shows you the last heard stations for that group. The Wiki button takes you to a Wiki page that, for some groups, has more information about it. But the really interesting button is the one marked Hoseline. You can also open the Hoseline directly which is what I usually do.

What’s the Hoseline? It shows activity across the network as a bunch of boxes indicating recently active talk groups. Boxes with red lines around them have people actively talking on them. The others have been recently active. It is visually interesting, yes, but that’s not the big selling point.

If you click on a box, you will hear the activity on that talk group. That’s all there is to it.

Overwhelming

There are a lot of talk groups. You can filter at the top left part of the page where it says “Everything.” You’ll have to drop the list down and unselect Everything. Then, you can select any countries or areas you want to follow. If you are brave, you can click RegEx mode and enter regular expressions to match talk group numbers (e.g. ^310.*).

The “Player” button at the top right gives you more control. You can add multiple groups from a list, see information about who is talking, and stop or start the audio.

If you prefer to do your listening mobile, you can also get the hoseline on your Android device. Just install the app, and you’ll find it works the same way.

Finding Something Interesting

Lord Nelson once said, “The greatest difficulty in war is not to win the battle, but to find the enemy.” That’s accurate here, too. Finding an interesting conversation out of all those talk groups is somewhat a needle in a haystack. A quick look around at the talk group lists might help.

The 91 and 93 groups stay busy but generally with short exchanges since they cover a wide area. The USA bridge at 3100 sometimes has traffic, too.

If you look at the group’s listing on the Web, you can click the group number and see what stations are connected to it. Keep in mind, some of these may be repeaters or gateways that could have no one on the other side, or could have dozens of people on the other side. But it can give you an idea if the talkgroup has any users at all.

You can also search the Internet for DMR nets and repeaters. Sometimes, it is interesting to listen to local repeaters. Sometimes, it is fun to listen to repeaters in other places. Want to find out what’s going on at your next vacation spot? Practice your French?

You can find many DMR repeaters using the RepeaterBook search page. There are also man lists of DMR nets.

Next Steps

There are many other similar networks, but they may not have a way to listen that doesn’t require some software, registration, or licenses. There’s plenty on Brandmeister to keep you busy. If you worry about people listening in, that’s no different than regular radio has been since the beginning.

You can always get your ham license and join in. Even without a radio, there are ways to talk on the network. [Dan Maloney] has advice for getting your “ticket.” It is easier than you think, and you can do a lot more with a license, including talking through satellites, sending TV signals over the air, and bouncing signals of meteors or the moon. If you want to listen to more traditional ham radio in your browser, try a Web-based SDR.

Although ham radio can be an engaging, rewarding hobby, it does have a certain reputation for being popular among those who would fit in well at gated Florida communities where the preferred mode of transportation is the golf cart. For radio manufacturers this can be a boon, as this group tends to have a lot of money and not demand many new features in their technology. But for those of us who skew a bit younger, there are a few radios with custom firmware available that can add a lot of extra capabilities.

The new firmware is developed by [NicSure] for the Tidradio TD-H3 and TD-H8 models and also includes a browser-based utility for flashing it to the radio without having to install any other utilities. Once installed, users of these handheld radios will get extras like an improved S-meter and detection and display of CTCSS tones for repeater usage. There’s also a programmer available that allows the radio’s memory channels to be programmed easily from a computer and a remote terminal of sorts that allows the radio to be operated from the computer.

One of the latest firmware upgrades also includes a feature called Ultra Graph which is a live display of the activity on a selected frequency viewable on a computer screen. With a radio like this and its upgraded firmware, a lot of the capabilities of radios that sell for hundreds of dollars more can be used on a much more inexpensive handheld. All of this is possible thanks to an on-board USB-C interface which is another feature surprisingly resisted by other manufacturers even just for charging the batteries.

If you were in Tunisia in October, you might have caught some of the Morse Code championships this year. If you didn’t make it, you could catch the BBC’s documentary about the event, and you might be surprised at some of the details. For example, you probably think sending and receiving Morse code is only for the elderly. Yet the defending champion is 13 years old.

Teams from around the world participated. There was stiff competition from Russia, Japan, Kuwait, and Romania. However, for some reason, Belarus wins “almost every time.” Many Eastern European countries have children’s clubs that teach code. Russia and Belarus have government-sponsored teams.

Morse code is very useful to amateur radio operators because it allows them to travel vast distances using little power and simple equipment.  Morse code can also assist people who otherwise might have problems communicating, and some assistive devices use code, including a Morse code-to-speech ring the podcast covers.

The speed records are amazing and a young man named [Ianis] set a new record of 1,126 marks per minute. Code speed is a little tricky since things like the gap size and what you consider a word or character matter, but that’s still a staggering speed, which we estimate to be about 255 words per minute. While we can copy code just fine, at these speeds, it sounds more like modem noises.

Learning Morse code isn’t as hard as it sounds. Your computer can help you learn, but in the old days, you had to rely on paper tape.