Removing Mold Stains

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The mildew stain is very ugly and does not come out of the clothes when washed. But things can be saved if you know how to do it!No need to throw away clothes with mould stains! Small mould stains can be removed at home, but if you have larger, stubborn stains, it’s worth going to a dry-cleaning specialist (if you can find one who still knows how). Be careful with the practices that are circulating on various gossip sites! The use of strong detergents in particular can easily lead to completely ruining an otherwise salvageable garment. And if the mould fungus has really got into the fibres of the cloth, there is no other way to help but with vinegar scissors…

Vintage Reed Frequency Meter

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The phenomenon of resonance has many examples in physics, engineering, and everyday life, and the reed frequency meter is one of them. Surprisingly, such instruments are still in use here and there, although they are certainly considered rarities today. I picked up this specimen, manufactured in 1961, for a few coins at a swap meet. … Read more

Reparing AURIOL LD3091 weather station

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My better half has a weakness for weather stations, and she especially likes this old piece. It’s not particularly smart, not particularly pretty, but it has a “frog”, which makes up for everything. It’s a cheap LIDL model — even the first one we bought didn’t pick up the signal from the external sensor. They replaced … Read more

Echoes in the Night: Spotting Bats with a Detector

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It’s well known that bats use their sonar to navigate their surroundings with remarkable precision. As part of this ability, they emit powerful ultrasonic sounds that are characteristic of each species. These sounds are inaudible to the human ear, but with a simple device, we can detect them — which can be great fun and … Read more

GANZ GLE-2 Stairwell Lighting Timer Switch

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This stairwell lighting timer switch was rescued for me from a building by a friendly electrician acquaintance of mine, Sándor Auffenberg. It had been removed because it was “misbehaving,” but it later turned out to be perfectly fine. According to its label, it was manufactured in 1991—so it’s 30 years old… I’ve written before about … Read more

Послание В. И. Ленина (Message from Lenin)

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In 2014, the Csepel spark telegraph station turned one hundred years old. The equipment transmitted messages from both Béla Kun and Lenin. I decided that for the 105th anniversary, I would build a spark transmitter myself. Csepel spark telegraph radio station The construction of the Csepel spark telegraph radio station, which marked the beginning of … Read more

Tuomas Aivelo: The Endless Parasites

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Format: EPUB. You can purchase it on Like.fi The Hungarian edition was published by Typotex Publishing Ltd. in 2021 and can be purchased at Typotex. You Are Never Alone! There are always guests inhabiting the human body—perhaps the most unsettling realization that most of us would rather ignore. A person can carry over 100 different … Read more

In memoriam calculatoris

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I found a handful of pocket calculators in a drawer. I haven’t used them in ages—Excel, MathCad, the software called Derive, and smartphones have taken their place—but I thoroughly enjoyed rediscovering their science! Once upon a time, they were important and expensive tools, and even today, machines with similar capabilities aren’t cheap. Yet they seem … Read more

The Power of Regex: A Beginner’s Guide

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This is a very old piece I wrote, even before the release of OpenOffice 2.4. I’m bringing it back because people often ask me for quick text editing tricks. I’ll show you how to do it using RegEx. The OpenOffice RegEx engine is quite usable. Microsoft Word can do similar things too, but it handles … Read more