Every Ham Shack Needs A Ham Clock

March 16, 2026 by Donald Papp 11 Comments

Every ham radio shack needs a clock; ideally one with operator-friendly features like multiple time zones and more. [cburns42] found that most solutions relied too much on an internet connection for his liking, so in true hacker fashion he decided to make his own: the operator-oriented Ham Clock CYD.

A tabbed interface goes well with the touchscreen LCD.

The Ham Clock CYD is so named for being based on the Cheap Yellow Display (CYD), an economical ESP32-based color touchscreen LCD which provides most of the core functionality. The only extra hardware is a BME280 temperature and humidity sensor, and a battery-backed DS3231 RTC module, ensuring that accurate time is kept even when the device is otherwise powered off.

It displays a load of useful operator-oriented data on the touchscreen LCD, and even has a web-based configuration page for ease of use. While the Ham Clock is a standalone device that does not depend on internet access in order to function, it does have the ability to make the most of it if available. When it has internet access over the built-in WiFi, the display incorporates specialized amateur radio data including N0NBH solar forecasts and calculated VHF/HF band conditions alongside standard meteorological data.

The CYD, sensor, and RTC are very affordable pieces of hardware which makes this clock an extremely economical build. Check out the GitHub repository for everything you’ll need to make your own, and maybe even put your own spin on it with a custom enclosure. On the other hand, if you prefer your radio-themed clocks more on the minimalist side, this Morse code clock might be right up your alley.

Pi Pico Learns Morse Code

February 10, 2026 by Al Williams 2 Comments

When [101 Things] didn’t want to copy Morse code, he decided to build a Pi Pico system to read it for him. On the face of it, this doesn’t seem particularly hard, until you look at the practical considerations. With perfectly timed dots and dashes, it would be trivial. But in real life, you get an audio signal. It has been mangled and mixed with noise and interference as it travels through the air. Then there’s the human on the other end who will rarely send at a constant speed with no errors.

Once you consider that, this becomes quite the project, indeed. The decoder captures audio via the Pi’s analog-to-digital converter. Then it resamples the input, applies an FFT, and converts the output via a complex classification pipeline that includes, among other things, Bayesian decoding. Part of the pipeline makes simple typo corrections. You can see the device do its thing in the video below.

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Building A Ham Radio Data Transceiver On The Cheap

October 3, 2025 by Lewin Day 19 Comments

Once upon a time, ham radio was all about CW and voice transmissions and little else. These days, the hobby is altogether richer, with a wide range of fancy digital data modes to play with. [KM6LYW Radio] has been tinkering in this space, and whipped up a compact ham radio data rig that you can build for well under $100.

Radio-wise, the build starts with the Baofeng UV-5R handheld radio. It’s a compact VHF/UHF transceiver with 5W output and can be had for under $25 USD if you know where to look. It’s paired with a Raspberry Pi Zero 2W, which is the brains of the operation. The Pi is hooked up to the All-In-One-Cable which is basically a soundcard-like interface that plugs into USB and hooks up to the mic and speaker outputs of the Baofeng handheld. The final pieces of the puzzle are a USB PD battery pack and a small OLED screen to display status information.

What does that kit get you? The capability to transmit on all sorts of digital modes with the aid of the DigiPi software package. You can send emails, jump on APRS, or even chat on the web. You can configure all of this through a web interface running on the Raspberry Pi.

We’ve looked at some interesting digital ham projects before, too. Video after the break.

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Roll Your Own SSB Receiver

August 19, 2025 by Al Williams 3 Comments

[Paul Maine] was experimenting with GNU Radio and an RTL-SDR dongle. He created an SSB receiver and, lucky for us, he documented it all in a video you can see below. He walks through how to generate SSB, too. If videos aren’t your thing, you can go back to the blog post from [Gary Schafer] that inspired him to make the video, which is also a wealth of information.

There is a little math — you almost can’t avoid it when talking about this topic. But [Paul] does a good job of explaining it all as painlessly as possible. The intuitive part is simple: An AM signal has most of its power in the carrier and half of what’s left in a redundant sideband. So if you can strip all those parts out and amplify just one sideband, you get better performance.

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The VLF Transformation

August 19, 2025 by Al Williams 6 Comments

People have long been interested in very low frequency (VLF) radio signals. But it used to be you pretty much had to build your own receiver which, luckily, wasn’t as hard as building your own VHF or UHF gear. But there is a problem. These low frequencies have a very long wavelength and, thus, need very large antennas to get any reception. [Electronics Unmessed] says he has an answer.

These days, if you want to explore any part of the radio spectrum, you can probably do it easily with a software-defined radio (SDR). But the antenna is the key part that you are probably lacking. A small antenna will not work well at all. While the video covers a fairly common idea: using a loop antenna, his approach to loops is a bit different using a matching transformer, and he backs his thoughts up with modeling and practical results.

Of course, transformers also introduce loss, but — as always — everything is a trade-off. Running hundreds of feet of wire in your yard or even in a loop is not always a possibility. This antenna looks like it provides good performance and it would be simple to duplicate.

Early radio was VLF. Turns out, VLF may provide an unexpected public service in space.

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Hackaday Links: August 3, 2025

August 3, 2025 by Dan Maloney 17 Comments

When all else fails, there’s amateur radio — and handwritten notes. Both ham radio and clear thinking helped rescue a mother and her son from a recent California camping trip gone wrong. While driving to the campsite in the Stanislaus National forest, the 49-year-old mother had the not-uncommon experience of GPS leading her and her 9-year-old son on a merry chase, sending her down a series of forest roads. Eventually the foliage got too dense for the GPS signals to penetrate, leaving the pair stranded in the forest with no guidance on how to get out.

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2025 One Hertz Challenge: Ham Radio Foxhunt Transmitter

July 13, 2025 by John Elliot V 9 Comments

[Jim Matthews] submitted his Ham Radio foxhunt transmitter project for the 2025 One Hertz Challenge.

This is a clever Spartan build. In order to create a radio beacon for use in a “fox hunt” [Jim] combined a SR-T300 walkie talkie module with a phototransistor and oscillating LED circuit. The phototransistor and oscillating LED are secured face-to-face inside heat shrink tubing which isolates them from ambient light. When the LED flashes on the phototransistor powers the radio which transmits a tone in the UHF band.

A fox hunt is a game played by radio enthusiasts in which players use radio signals to triangulate and find a hidden beacon. [Jim]’s circuit is the beacon, and when it’s powered by a three volt CR2032 battery, it transmits a strong signal over several hundred yards at 433.5 MHz, within the amateur radio UHF band.

If you’re interested in radio beacons you might like to read about the WSPR beacon.