M0AGX / LB9MG

Amateur radio and embedded systems

  • Youkits TJ5A

    The Youkits TJ5A is now my primary transceiver. I bought it with portable operation in mind (I do not have much space for decent antennas at home). Read more for high-resolution photos.

    tj5a_4

    Pros:

    • Very good filters (in terms of selectivity)
    • Built-in battery pack
    • 20W output power (peak SSB)
    • Robust construction …
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  • MG-log for Android

    I released MG-log version 0.6 to Google Play store this week. It is now a quite practical app. I made my own log for Android, because I could not find a QSO logging app that would be easy to use during portable operation and not cluttered. A log for …

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  • Serial port redirection from Windows to Linux with socat

    My work computer is a Windows machine running several virtual machines with Linux and FreeBSD via VirtualBox. A part of my work requires developing software that interacts with hardware. Most of the time I have successfully used VirtualBox USB filtering to redirect USB devices to the virtual machines but recently …

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  • Gentoo on Banana Pi

    I like to use Gentoo for most of my tasks (except the smallest systems that run OpenWrt). I also wanted to have it on the Banana Pi. I did not find any specific manual for Gentoo and the Banana so I followed the standard, two-step installation manual for any architecture …

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  • RRDtool - quick tutorial

    RRDtool is both a database and a graphing tool that is well-suited to visualize time-varying data like temperature, pressure and all kinds of telemetry.

    There are many tutorials available, but they dig too much into the details (like the official one). Since I use RRDtool only for storing and graphing …

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  • Banana Pi on battery power

    The Banana Pi is a great alternative to the well-known Raspberry Pi. It is not a clone, nor a knock-off, rather a completely different, open single-board computer of a very similar size and good price. Most important features (compared to Raspi) to me are the 3 UARTs (one for the …

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  • Small, cheap power supply modules from Aliexpress

    I have recently bought a BananaPi with the intent of making a automotive datalogger. I needed a simple power supply that would work reliably in my car. I found some nice looking modules in "The Thick Electronic" store on Aliexpress.

    psu

    This shop has many different DC/DC modules that can …

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  • Universal antenna rotator controller

    This is one of my older projects. I designed it for a friend of mine when he became fed up with his Rot1prog controller going bonkers all the time. I wanted it to be something as simple as possible, but still doing its job, easy to use and easy to …

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  • NodeMCU as a standalone thermometer

    I finally completed work on my networked thermometer. I got some old 7Ah 5-cell NiCd battery packs from emergency lighting fixtures that will power the device. I wonder how long can they last. NiCd batteries suffer from high self-discharge rates, on the other hand the NodeMCU will sleep most of …

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  • B6AC battery charger teardown

    I recently got some discarded NiCd batteries from emergency lighting fixtures (5 cells, 7 Ah) and I started looking for a way to check if they might still work. While searching for chargers I found model B6AC that charges automatically almost any battery chemistry (various lithium, NiCd, NiMH, lead-acid), can …

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