I’m going to be attending Make magazine’s Maker Faire April 22-23rd, San Mateo, CA. It should be a lot of fun.
This is my event schedule for the rest of the year. Feel free to suggest events I should be attending.
Maker Faire, April 22-23rd, San Mateo, CA
Hope number six, July 21-23rd, NYC
Siggraph 2006, August 1-3rd, Boston
Defcon 14, August 4-6th, Las Vegas
Toorcon 8, September, San Diego
The RepRap project hopes to build a universal constructor; a machine that can replicate itself and make a number of useful products. The machine is open source and uses fused deposition modeling (FDM) to layer melted material into parts. One of the key technologies in self-replication is the ability to lay conductive circuit paths. The RepRap machine is able to lay down conductive material and an insulator. For a conductor they are using Wood’s metal, a fusible alloy that has a melting point of 158degF. To demonstrate this conductor laying ability they built the FDM head pictured in a commercial FDM machine. The project makes some reasonable compromises; it doesn’t attempt to make common items like brass bushings, microcontrollers, stepper motors, self-tapping screws, and power supplies.
The Sony PEG-UX50 was an impressive package when it was released in 2003. It had a 480×320 screen, keyboard, convertible screen, built-in camera, WiFi and Bluetooth. As with most portable devices, the short time the battery stayed charged left much to be desired. Sony sold an EB40 battery pack that piggy-backed the device, but reader [JAmerican] wanted to extend its charge even further. It took a little dancing around with the charging circuit, but he was eventually able to combine 4 batteries to construct a 3880mAh battery that keeps the UX50 running, even after 9 hours of use. Here’s a site with a decent photo gallery of the UX50 (at the bottom).
I had seen the link for Jonathan Westhues’s original proximity card spoofer floating around recently and decided to check out the site to see if anything had changed since we originally covered the story. Well, he’s got a brand new version. This one has far more features than the original, mostly because of the extra processing power provided by an Atmel AT91. The new spoofer can handle multiple modulation schemes; which means it is capable of copying almost any 125kHz or 13.56GHz ID-only card. Although it can’t clone cryptographic cards, it does have a full feature set for communicating with them. By connecting the USB port to a computer you can see an “oscilloscope view” of the signal from the card to assist in writing demodulation code. If you are serious about doing RFID research this hardware is a must-have. You could buy a standard reader, but that would tell you nothing about the protocol. This is definitely a clever tool and certainly impressive for something smaller than a business card.
UPDATE: Jonathan Westhue’s work was mentioned in a CNN story Feb 14th. You can watch the video here. [thanks David]
I just saw this MSN TV Linux Cluster over on Engadget. The boxes have a 733mhz Celeron, 128MB RAM, 2 x USB, Ethernet, and a 64MB CF card for storage. That’s twice the RAM of an Xbox and with a node cost of $0.99 it makes a much more sensible and compact cluster. The only limit right now seems to be a 64MB capacity cap for the CF card.
You do need to build a level shifting serial cable to talk to it though. Microsoft included serial pins on the board, which is convenient. I think that a TTL to RS-232 level shifting box is becoming the second most useful device behind the bench power supply. You need to do serial level shifting whether you are talking to an NSLU, iPod, GP2X, or WRT54G. You might as well make the thing USB while you are at it. So, who wants to do the how-to?
Amongst PDAs, cellphones, portable game consoles, and digital audio players USB host mode isn’t that common. The lack of host mode is why you can’t plug your iPod into your PSP. The iPod camera connector is a partial work-around for this problem. The Linux based GP2X gets more interesting with this new development. Using the GP2X’s USB host requires building a special cable for its expansion port. The port features JTAG, serial, audio, and video pins as well. USB host mode opens the doors for any number of USB peripherals to be used with the GP2X: larger storage from a hard drive/iPod, full sized keyboard for use with a command line, WiFi provided by USB adapter. There is the potential to do anything that you could do with a standard PC. If I had known this I would have bought a GP2X without a second thought… so, after two thoughts I bought one and it showed up last Friday evening. I’ll let you know how it works out.
Pete (AC7ZL) wrote in to tell us about his latest project: building a flat response microphone and channel amplifier. You may remember his previous project: building a crystal radio from modern junk. Sounds are “colored” by their surroundings; things like furniture, wall coverings, drapes and building materials all affect the way something sounds. To measure the effect that a space has on sound you need a microphone with a flat frequency response. The core element of Pete’s mic is a modified Panasonic WM61A condenser capsule. He rewired it so that it had a broader dynamic range and could handle a higher SPL at the cost of reduced gain. To boost the signal to a usable level he built a preamp with three stages of amplification. He’s got schematics and a more detailed description on the site.
