The Youritronics electronics lab has a new look: 2 new benches and shelves all of them hand-built. When space is an issue you really have to make the most out of it. One thing is sure, I need more Ikea plastic boxes. On the first bench I do most of the electronics stuff while on the second one I do all the other stuff like assembling – disassembling or breaking stuff. Also on the second bench you can see my DIY reflow oven.
You’ve probably seen the article about the Asus Eee PC and what can be integrated inside it’s case. But after you’ve done some modding and added different devices your battery probably doesn’t last as it was intended to last, so if you need to charge it in the car you either buy a commercial adapter or you make it.
This projects shows details on how to build an Eee Pc car charger. There are actually a small number of parts so the whole cost should be small.
ASUS Eee Pc Car Charger: [Link]
The muscle powered Dice is based on Faraday’s law, consisting of a tube with cylindrical magnets. The tube is wound with a coil of magnet wire. As the tube is shaken, the magnets traverse the length of the tube back and forth, thus changing the magnetic flux through the coil and the coil therefore produces an AC voltage which is used to drive the electronic dice. Pretty simple now that you know how it’s done 🙂
Electronic Batteryless Dice: [Link]
In my opinion a very original idea, because I’ve never seen a eletronic stethoscope. And besides the originality you’ve got functionality which is great. The stethoscope gets the sound trough a microphone place inside the classic stethoscope sensor. The temperature and pulse are showed on a 3 digit 7 segment display.
This schematic is ment to digitally display the output of an electronic Swissflow SF800 flow sensor. This sensor puts out an open collector square wave signal (like a fan RPM monitoring signal) between 50Hz (=0.5 liter/minute) and 2000Hz (=20 liter/minute).
By dividing the measured frequency by 10 and putting the decimal point at the right place you get directly a display in liter/minute. I don’t use the first digit output (output D) from the 74C925 to obtain a display of 10 to 9990Hz or xx.x liter/minute.
3-Digit Frequency Meter: [Link]