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What "extremely hot" means in Sweden

Last summer in Sweden 2014 we had like five days straight with temperatures around 28 celsius (82 fahrenheit) during the day. Such temperature is considered more or less extreme and during such circumstances things go bad for some of us frozen swedes. Yeah, you read correctly, that is extreme for many of us. You're laughing right? Come here when it's -5 celsius instead and see who has the last laugh ;) Alright, I'm exaggerating a little. bit Most people like temperatures as such. But I believe I found an exception here.


Most housings in Sweden don't feature a cooling system, which is reasonable. I mean, it would be sort of the same thing as opening a sand shop in the desert of Sahara. However, sometimes maybe there is a need for sand even in Sahara. Some fellow engineering student (I guess), suffering in his rented student housing in Gothenburg, found a remedy to his hardships. Down at the yard there was a storage room for solid waste were disposed fridges ocassionally could be found. To shield himself from this burning inferno he mounted the fridge in the window of the apartment. That's right, when there was 28 celsius in Sweden some guy mount a fridge in his, or perhaps her, window. If the top part of the opening of the window was covered for the system to actually work is unknown.

This however reminds me of a deeper aspect. There is so much useful material that just goes to waste in Sweden, while it could sometimes be directly recycled, like here. Okey, this is not a great example, I don't expect people to mount old fridges in their windows. But a lot other stuff that is thrown away is fully usable.

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[VAWT] Plausible improvements of the Savonius windmill

Cut a barrel in half, mount it on a shaft and you have a windturbine. If the barrel is used, then what else probably would end up on a scrap heap is instead used for converting renewable energy.

Simplicity and low cost makes this an attractive option especially for societies with limited economy and a malfunctioning or non existing electric grid. Small off-grid electrical networks can be built and people who perhaps most needs electricity get that. Isn't that neat?


Savonius (from http://solarvan.co.uk/savonius)

An overlooked potential?
The Savonius though has a widespread reputation of having low effiency and is often dismissed as a credible option around forums and in formal litterature. However, when looking at the graph below from a publication Wortman did 1983, the effiency can be realtively high provided that the TSR(Tip-to-Wind-Speed-Ratio) is held at a correct value and the windmill should work quite nicely. In practice this could probably be done by controlling the generato…

[VAWT] Affordable wind measurements

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The WH-1080 spare anemometer

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Guide: Get more distortion from an HCM65R amp

I got my hands on an HCM65R guitar amplifier. It's an okay amp I guess, if anything it's loud enough to rise a mob against you even if you live off in a rural area. But, something that's been bothering me and many fellow reviewers it is that it lacks distortion. For me it's usually enough for blues but some palm muted metal, like Into the void with Black Sabbath, comes out a bit soft.


As both of the volumeknobs were broken I took the amplifier apart and started thinking about a way how to get this loudly purring kitty to growl like a beast. When taking it apart I saw that the PCB is really old school with large components placed with a lot of space between them. So, hack friendly! I found out what to change and how, tried and it worked. Check the video below to hear how different it got.

Demonstration I play some random stuff with and without the modification and I think that the difference in tone is very clear.


How to do it This is for you who knows how to solder and…