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Submission + - So You Want to Flap Your Arms and Fly?

Maddog Batty writes: "Take the accelerometers and gyroscopes from an HTC phone and a Wii remote (http://www.humanbirdwings.net/about/haptic-wing-mechanism/) and connect to your battery powered flapping mechanism. Make the wings from your old kite and add ribs to give the correct profile. Attach to back, run down field, flap arms, take off and fly! (http://www.humanbirdwings.net/) Warning there is a bit of swearing at the end of the video (http://youtu.be/GYW5G2kbrKk). Note: this is battery powered flight not human powered but very cool nevertheless."

Comment Re:No (Score 5, Informative) 502

No it isn't fiddling with numbers. You are missing the heat pump bit.

The device is taking X amount of energy from the electricity supply and X * 1.3 of energy as thermal and converting this to X * 2.3 as light. i.e. it is 230% efficient when comparing light output to electrical input. Equally, it is 100% efficient when comparing light output to electrical and heat energy input combined.

This does take a little bit of thinking to get your head around but I have a more common example in the shed outside. It contains a heat pump which is 350% efficient. It takes 2kW from the electricity supply and outputs 7kW of heat energy to heat my house. The missing 5kW comes from the pipes in the garden as heat energy. The result being that the garden is slowly being cooled. http://en.wikipedia.org/wiki/Heat_pump

Comment Re:Magnetics (Score 1, Troll) 132

I have no idea what this means. How is this possible?

I guess because you didn't study properly at school... ;-)

"Without them you would effectively tie the RX and TX signals together and probably turn the entire network into an aerial for Radio 2 reception."

I disagree with the first part of this. Ethernet works off differential signals and the transformer does a good job of removing the common mode signals (non differential) coming down the wire. Without the magnetics the common mode signals (such as DC, mains interference, Radio 2 transmissions) picked up by a potentially long ethernet lead will turn up at the input to the ethernet phy (receiver) chip. This may or may not be enough to stop it from working depending on the interference received. The lack of correct voltage biasing (also done via the magnetics) will very likely stop it from working though. Even so the RX and TX won't be shorted.

Submission + - The Fallout from a Flickr DMCA Takedown

Maddog Batty writes: "Dave Gorman ( http://en.wikipedia.org/wiki/Dave_Gorman ) a UK comic and Flickr user recently received a DMCA takedown notice for one of his own pictures (copy http://www.flickr.com/photos/dgbalancesrocks/6800943616 ) which had become rather popular — 160,000 views + lots of comments. The takedown was in error (from a porn company) and Flickr allowed him to repost the image. However, the fallout ( http://gormano.blogspot.com/2012/03/if-this-picture-looks-bit-familiar-it.html ) is that all the original comments are now lost and the many links to the original picture are now broken. Sure Flickr needed to remove the image, but surely there should be a way to reinstate it keeping all the original comments and links?"

Comment Re:Perhaps study these treatments scientifically? (Score 1) 566

Studies have repeatedly shown that prayer helps in hospital situations. Why? Maybe people just feel comforted or a sense that somebody cares about them and wants them to make it. What's the scientific explanation? I haven't seen a good one. But more people recover and have less complications.

Show me a double blind experiment which shows prayers work? Properly conducted double blind experiments has shown that prayer does not work. The experiments which do show a result, the patient knows that they are being prayed for and/or are doing the praying themselves. Sure it may help these people but this is due to the ritual causing the person to self heal. No super power is involved at all.

If you disagree and think prayer does work in the double blind, go and speak to http://www.randi.org/site/index.php/1m-challenge.html and he will give you $1million when you succeed.

Comment Re:Assumptions (Score 1) 240

44pin Quad Flat Pack are trivial to remove and replace with the right tools - which basically means a hot air gun with the small nozzle. A couple of weeks ago I removed and replaced two 144 pin quad flat pack devices with 0.6mm pitch legs in about 10 mins. It isn't something I want to do for production boards but it is fine for the development boards I was using.

Screen printing solder using solder masks + ovens are easily within the hobbiest market now. You can get a custom PCB + solder stencil made for £40 (100mm^2) and I use a £50 oven to melt the solder. Gives good results too (though I still do the sub 1mm pitch pins by hand as I get too many shorts otherwise).

I've not attempted BGAs as I could see that the success rate might not be too high.

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