Unlimited cellphone calling for cheap

nextel

Every couple months I get a tip about how to get unlimited calling for minimal money. They usually involve some less than elegant forwarding, but I figured I’d post one and hopefully be done with this topic. Here is [van12]‘s version posted on Howard forums. First you need a cellphone plan that has free inbound/outbound calling to your home … Read the rest

Computer controlled light cube

led light cube

[Alex Hornstein] was bored one Saturday and decided to do something with the large pieces of scrap acrylic he had found. He built a cube and attached 15 RGB LED clusters along with 4 GB LED sticks. It takes 50W of power. The controller is built from ATmega48 and is controlled via serial commands over a wireless link from Spark … Read the rest

Sound based Airsoft chronograph

airsoft chronograph

Seattle Airsoft has a great post on measuring BB velocity using a microphone. They use two pieces of paper separated by 10 feet with a microphone by each one. Audacity is their program of choice for recording. If you look at the waveform after firing you’ll see three distinct spikes: one from the firing mechanism and one from each … Read the rest

VGA CAT5 extension cable

rj45 cable

[Ladada2001] sent along a project link for building a VGA extension cable using CAT5. This particular project was for a projector with BNC connectors. This has been a particularly popular (and easy) topic in the past. We’ve seen an example from ElephantStaircase. The 5-in-1 cable featured in Make also had provisions for VGA. If you build one of … Read the rest

Peltier beverage cooler

peltier beer cooler

Hacked Gadgets pointed out this great peltier based beverage cooler. It has a pulse width modulation based controller driving a 12V 80W peltier. Alan also pointed out Hack-A-Day reader Chris Garrison’s peltier beer cooler from last summer. The Defcon cooling contest from last year also featured a peltier based cooler.

[UPDATE: Afrotech’s Snapple Cooler or How to enhance … Read the rest

Ridiculous laser wall clock

servo controller

[nickjohnson] has produced an incredibly silly laser wall clock. It was built to test out his PWM servo controller board. He created a wall poster featuring numbers 0-9, hour, minute, AM, PM. The controller points at each symbol in sequence to spell out the time. It changes position every second which creates a nice ticking sound. The clock … Read the rest

DIY optical disc duplicator

[matt] wrote me a couple weeks ago wondering how to build a robotic arm that can load and load/unload a CD or DVD from a drive. I told him about one built out of wood that I couldn’t find the link for. Matt wrote back to say he had found the Home built CD changer contraption. The design is … Read the rest