Sometimes household appliances cause (significant) electromagnetic interferences in our receivers. Unfortunately, replacing them isn’t always an option. Fortunately, adding common-mode chokes to the input and/or output cables can drastically reduce the emitted interferences. Choosing the right ferrite material is probably the most important success factor. In this post, I compare three different materials and show how you can measure and evaluate (random) ferrite cores by yourself!

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The year 2020 started with outstanding tropospheric VHF propagation here in southern Germany. For the first time, I was able to copy the VHF beacon GB3NGI from Northern Irland at a stunning distance of 1300km. Read more about this great opening and listen to the audio recording I made.

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The ST-Link/v2 is an in-circuit debugger and programmer for the STM32 and STM8 microcontroller families. Due to its capabilities, it is an extremely popular device and clones are available from your preferred Chinese trading platform for less than 5 euros. I recently ordered a few of these cheap ST-Link/v2 clones for a new project. However, making them work was pretty frustrating. Read on to learn about the problem, the symptoms, and the (super) easy fix.

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Both ICOM radios, the IC7300 and the IC9700 allow a variable transmission (TX) delay. This comes in handy if external peripherals like amplifiers and/or pre-amplifiers are used. These devices often have slow mechanical relays. It is good practice to wait until the complete transmission chain is ready before RF is applied. Out of curiosity, I measured and verified the adjustable tx delay on both radios.

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One of Golang’s strengths is that it supports cross-compiling to any common Operating System and CPU architecture out of the box. However, that’s only true for projects written in pure Go. Normally that’s not a problem, but sometimes we depend on 3rd-party C libraries… and that’s when things tend to get complicated.

In this post, I will explain how you can cross-compile your cgo project for multiple operating systems and architectures in a clear and structured manner.

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Author's picture

Tobias Wellnitz, DH1TW


Software Engineer

Germany