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Last summer my old WS2300 weather station finally gave up, after 15 years of service. So I bought a new one, the Waldbeck Halley Professional Weather Station (also known as WH2650A-WIFI6C6F). This device can log some data (basic outdoor measurements)…
For just a few dollars you can buy a small board that acts as a bluetooth audio device. This board allows you to build your own bluetooth speaker. But why build a new speaker when you still have an old…
I often get questions about what filament I use for 3D printing, so I thought it would be nice to write a short article on this subject.
I always have been fascinated by growing things in an automated way. For instance, I absolutely adore the FarmBot project and would really like to build such a machine once I’ve got time and money for it. Until then, I…
Geocaching is a popular hobby here in The Netherlands. Since my wife and I search for these caches from time to time, the idea came to me to build a cache myself, one that challenges geocachers to listen and decode…
Almost every nerd is a fan of automation. So whenever we find a repetitive job, we think of a solution to automate it. Since I’m both into automation and amateur radio, I was thinking on automating one of my straight…
After three years of frequent operation, I decided to replace my Anet A6 3D-printer with the new Creality CR-10s Pro. I must say I’m very happy with this new machine in my shack: it’s easy to operate, the print quality…
Nowadays breadboards are often sold with a breadboard power module and a bunch of jumper wires included. This power module allows you to easily apply 5 and/or 3.3 volt to the power rails of the breadboard using an external power…
Time… For some reason we tend to stick to an ancient system which has no logic at all. Let’s be honest: if we would invent a new time system nowadays, it would probably not have 7 days in a week,…
During the summer season bats fly around almost every day in the twilight. I spot them in the evening, when they fly along our house and hunt for small flying insects, mostly mosquitoes and flies. Their soundless air show is…
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Adrian PA0RDA heard about the SOTAbeams Go4Lo SWR-Power Indicator. Since it has an audible SWR indicator, it sounded interesting for blind operators. So he ordered a kit and asked me to build it. This article discusses my findings regarding this…
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3D printers are getting more affordable now, and although I originally bought one for my wife, I was absolutely certain that it would be useful for my home brew stuff too.
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Recently I have transferred the CLog software to my GitHub repository. I’m currently centralizing my code at GitHub since I wanted to get rid of sourceforge.net (my previous repository for CLog) and prefer GitHub nowadays.
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The Neophyte receiver is an easy-to-build receiver, already built by lots of people. Many radio clubs used it as a project for starting builders. It was developed by John WA3RNC and first published in QST, February 1988. The circuit can…
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This article is about receiving radio stations operating in the VLF band (3-30 kHz). Due to the very low frequency, receiving such stations requires some special equipment, since most radios don’t support these low frequencies. One of the interesting stations…
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When you started discovering microcontrollers, you probably bought some kind of evaluation or prototype board. The microcontroller chip itself is placed in a nice socket on a PCB, surrounded by power circuit, some I/O, and RS232 or USB connector for…
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I’m the proud owner of a MiniVNA for quite a few years already. One of its features is that you can use it as an RF signal generator. However, the output power cannot be adjusted, so I needed an attenuator.…
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Many years ago I built a prototype of the famous “Pixie 2”, one of the simplest and smallest CW transceivers ever designed. The main issue is that the TX and RX frequency is the same, so the opposite station needs…
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In the previous Winter I built a HB9CV-in-a-box for 23cm for my uplink to the local ATV repeater PI6ATV. Although this antenna works nicely, its gain just isn’t enough when their 23cm preamp is broken (which, unfortunately, is the case…
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Using a paddle to operate in morse code is very convenient. But paddles don’t create dots and dashes on their own, so you need some electronics, called a “keyer”. You may use the build-in keyer of your radio, but most…
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This year I built a very nice 30m QRP transceiver, based on a design by Onno PA2OHH. Meanwhile I have used this rig a couple of times, and did some measurements too. This article tells some of my experiences with…
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I found a really simple project for kids to attract them to homebrewing and hamradio. It is also very nice for people who want to learn soldering electronics. It’s a “signal tracer”, which means it detects all kinds of RF…
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Lots of radio amateurs build their own verticals. Most of them tend to stick to vertical antennas with a 1/4 or 1/2 wave sizing. Just a happy few build a 5/8 wave vertical antenna. This is remarkable, since the 5/8…
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The dutch electronics shop Van Dijken Elektronica sells a nice kit to build your own LC meter. The kit includes a professional PCB, all components, building instructions, prepared case and leads. The kit takes an evening to assemble, the result…
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A while ago Tjeerd PA3GNZ donated me some Barkleys mint tins (identical to the famous Altoids tins), which are rather popular by QRP builders to house small homebrew stuff. Two weeks later I found a czech webshop, offering a kit…