Measuring SMD parts with a home brew version of Smart Tweezers

SMD parts are great; they allow you to pack more parts on a board, do away with drilling dozens of PCBs, and when done correctly can produce a factory-quality board made in a home lab. There’s one problem with SMD parts; troubleshooting and measuring them. The ideal solution would be something akin to the Smart Tweezers we’ve seen before, … Read the rest

PIC LC meter improvements add Li-Ion battery and charging circuitry

[Trax] needed an LC meter and decided to use a tried-and-true design to build his own. The only problem was that he didn’t want to be tied to a bench supply or power outlet, which meant a bit of auxiliary design was in order. What he came up with is the battery-powered LC meter you see above.

The core … Read the rest

Using an Arduino to measure inductance

Measuring an inductor is not something that most multi-meters can do. You usually need a high precision resistor (1% or better) in series with the inductor, a function generator to put a signal through the circuit, and an oscilloscope to measure the result. But what can you do if you don’t have these tools on hand? [Andrew Moser] has a … Read the rest

555 inductance meter

[Apexys] is performing some experiments with switched-mode power supplies and needed to compare the inductance of the coils he was using. His multimeter doesn’t have an inductance testing function, but he does have a 555 timer on hand. He put the 555 and some other parts together to create his own L meter. The writeup includes the theory behind … Read the rest

Theory behind evanescent wave coupling, aka wireless power

[Alan Yates] is building a persistence of vision display and needs a way to transfer power from the stationary base to the spinning circuitry. He’s decided to go with wireless energy transfer and he’s sharing all of his research and experiment data from the development process. It comes in two forms, the written version we just linked to, and … Read the rest

Floating globe, hacked to rotate

they need to hire this guy

[Alexy Sha] has done this fantastic hack, where he modified a magnetic floating globe to be motorized and spin on a tilted axis. The original globe was simply levitating via a magnet mounted inside. Though you could spin it by hand, it wasn’t motorized, and actually floated completely vertically instead of being tilted.

[Alexy] wanted to take this idea … Read the rest

Inductive cellphone charging without voiding warranty

[Derek Hughes] wanted to use inductive charging on his cellphone without voiding the warranty. He picked up a Pixi charging backplate meant for a Palm Pre and scavenged the coil and regulator circuitry from it. To make the electrical connection with his HTC HD2 he removed the mini-USB plug from a charging cable and connected it with 30 gauge wire. … Read the rest