Building a 100 W electronic load – part 1

Since I work a lot with batteries and power supplies, I often need to test them, usually by loading them with different currents. While you could build a high power resistive decade (out of 1 and 10 ohm resistors – I did this when I started with electronics), an electronic load will give you much … “Building a 100 W electronic load – part 1”

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Measuring thrust of cheap 1S coreless motors (for a possible ESP32 μdrone)

I recently took part in a hackathon, where each team was given a DJI Tello drone for hacking. We had a lot of fun and I really liked this small, nimble drone, which could be flown inside and had a camera, which allowed you to stream video to your computer via WiFi (and then for … “Measuring thrust of cheap 1S coreless motors (for a possible ESP32 μdrone)”

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How to panelize PCBs in Eagle

These days, you can get custom PCBs made really cheap – a few dollars for a couple of 100×100 mm boards, complete with silkscreen, vias, everything. But even with these low prices you might want to have a couple of smaller boards produced on one, larger board. Let’s clarify something first – I won’t be … “How to panelize PCBs in Eagle”

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Nokia 5110 screen replacement

For the past couple of years, I’ve been using the Nokia 5110 84 x 48 px monochrome display for most of my projects. They are really cheap, small and easy to use while providing enought screen estate to display a couple of variables or sentences. But they have their downsides, the biggest being their terrible … “Nokia 5110 screen replacement”

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3D printing a stencil for applying solder paste

If you ever tried making more than a couple of the same PCBs at once, you probably came to the conclusion that soldering it by hand sucks and also takes a lot of time. The alternative – which is also how they do it commercially – is the so called reflow soldering. Simply said, it … “3D printing a stencil for applying solder paste”

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Testing the range of RA-01 (LoRa) modules and comparison against NRF24 and ESP-LR

Wireless communication is fascinating for me, but since I do not know much about RF electronics, I am stuck with what pre-made modules I can buy. And, of course, one of the most important parameters of a radio module is it’s range. But strangely, this information is very scarce on the internet and I don’t … “Testing the range of RA-01 (LoRa) modules and comparison against NRF24 and ESP-LR”

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Update to my Brymen 867/869 interface cable

If you ever read any other articles on my blog, you know that most of them are about devices I’ve constructed and used for a while. So I do not publish immediately after I finish a construction, because I prefer to use the device for a while and then summarize my experience with using it … “Update to my Brymen 867/869 interface cable”

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My Open Source Multimeter – final revision

So I finally arrived at the point where I consider my Open Source Multimeter finished. It is not perfect, but it is more than good enough for my purposes and I also do not have time to develop it any further (at least for now). So in this article, I’ll descibe what I came up … “My Open Source Multimeter – final revision”

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AVR-based Li-Ion battery charger

If you ever worked with lithium batteries, you probably know the TP4056 – a chip for charging lithium batteries with CC-CV profile, two LEDs for state-of-charge indication, temperature input and so on. You can find it relatively cheaply on Ebay or similar sites, either as standalone IC or on a small and very practical breakout … “AVR-based Li-Ion battery charger”

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