I thought everyone was going with cheap PC based power supplies(I did), but some people just have to take it to another level. [andrew] built this bench PSU with -12V, -15V, +5V, +12V, +15V, variable and one +35VDC unregulated output. He based it on this design, but added a few tweaks of his own.
Yes, Hack-A-Day took a bit of an unplanned hiatus on Saturday, but I’ll have some extra stuff for you this week as things return to normal. If you’ve got something interesting, use the tips line.
Misc Hacks4137 Articles
Superglue Fingerprinting
Just a fun one right out of Beverly Hills Cop. [Sam] sent along this handy how-to for obtaining finger prints with CA adhesive(superglue) fumes.
DIY Digital Voice Transceiver
[dk] sent in the DVX project. It’s a complete D-STAR implementation that’s built around a digital transceiver chip, an ATMEL mcu and a digital voice compression chip. Compared to most digital radio’s I’ve seen, this one is pretty simple. The really complex action lives in the main chips with a bunch of caps and resistors to support them. Watch out for Digikey’s pricing – it looks like a major gouge after looking at the tx/rx chips on Analog Device’s site. If you get them at a decent price, they could make great rf links for your projects. The link to the paper seems a bit broken, but here’s the correct one.
Visual Computer Pong Player
I think it’d be more fun if the computer had to actuate a joystick, but [ashish]s visual based computer pong player is still pretty sweet. He’s capturing the game state with his webcam, and the computer processes the image and controls the pong paddle via tcp client connection based only on what it sees.
Voting Rom Swapped In 60 Seconds
It’s been a while since we had a voting machine hack, but this video that [Marcel van der Peijl] sent in not only reminds me of Real Genius, but makes a great point. Maybe one of these voting machine companies will wake up, bring some decent designs to a hacking con and get things right. These guys popped apart a machine and fully swapped the roms in 60 seconds. How’s that for stealing a vote?
Knock Response Automatic Door Opener
I’m at the beach this week – finally on vacation. Thanks to DD-WRT, I’ve got a handy wireless repeater to keep the beach house covered with network access. [sprite_tm]’s doing his best to make my vacation easier. He built this knock activated automatic door opener for a friend who wanted easy access to some locked, but empty flat (think british apartment) rooms. He used an ATTINY with some fets to drive the stepper (you can find those in old dot matrix printers for free) and a small transistor amped mic circuit to pick up the knocks. Knock the right code, and you’ll get let right in.
Wireless Lightbulb
[atrain] sent in this interesting wireless light bulb. It’s more of a wireless powered LED inside a lightbulb, but you get the idea. A RF signal is recieved by a coil inside the bulb – the AC signal is rectified and used by LEDs to create the light. All the technical details you need to build your own are here.
