Repurposing server PSU for your charging needs

That grey box at the top of the photo is a modular power supply unit for a rack-mounted server system. [Sebastian] decided to repurpose it as a charging source for his RC batteries. He chose this HP DPS-600PB because of its power rating, efficiency, and you can get them at a reasonable price.

This is an active power factor … Read the rest

High speed photography controller built to catch water droplets

One high-speed photography controller to rule them all. If you’re looking to photograph droplets of water splashing on a still reservoir this is the ticket. But if you’re not, it still offers an incredible amount of flexibility for other high-speed needs. Inside you’ll find an Arduino Mega, which has plenty of room to bend to your will.

[Michael Ross] … Read the rest

Make your own magnetic ink

Here [Catarina Mota] is showing off a ring of magnetic ink printed on a piece of paper. It’s strong enough to hold a disc magnet in place when the paper is raised vertically. This strength comes from mixing your own batch of ink.

Magnetic ink has been around a long time and is most often used in banking. … Read the rest

Optical fiber twin-flash adapter

[Marcell] has always been turned off by the price tag of commercially available double flash adapters. He decided to see what kind of performance he could get out of a flash adapter which he built himself.

The raw materials used should seem quite familiar. The optical fibers act as a conduit to redirect the light from the flash, but … Read the rest

Store your RFID transit card inside your cellphone

Check it out, this is a Boston transit pass — or at least the parts of it that matters. [Becky Stern] got rid of the rest in a bid to embed the RFID tag inside her cellphone.

The transit pass, called a CharlieCard, started out as a normal credit card shaped tag which you might use for access in … Read the rest

Retrotechtacular: The birth of satellite communications

Last week was the fifty year anniversary of the launching of Telstar 1, the first communications satellite. Take a look back at the marvel of the early technology as shown in this newsreel footage about the first broadcast. The first formal use was a speech by President Kennedy allowing most of Europe to “witness democracy at work”. You’ve got … Read the rest

Lightweight web server using the MSP430

Need a tiny web server? [Rob] over on the 43oh forums made an Ethernet booster pack for the very popular TI MSP430 microcontroller. If that’s not enough, [Rob] also put together an all-in-one solution with a MSP430 and Ethernet controller that can be powered by a battery. Along with the web server that fits in just 5k of flash, we’re … Read the rest