[Jesse] sent in this beautiful 300 watt amp project. It uses six LM3886 amps to create a pair of 150 watt amps that are bridged to create a single 300 watt amplifier. Usually I don’t mind my lack of multi-language ability, but many of the parts were sourced from this site. It looks like the cases were bought in Hong Kong, anybody know were I could get some in the US?
Misc Hacks4177 Articles
DIY Condensor Microphone
[wiesi] sent in his latest condenser mic. Rather than use pre-built components, he built from scratch (except the discrete components). He’s on his second iteration, and things look pretty good. This tends to be the sort of project that amateur radio guys go for… oh wait, I am one.
DIY Plasma Gun
[Richard] took another shot at his battery powered tesla coils. He sent in his latest hand held plasma gun. He modified his battery powered tesla coil to work as a handheld. He added a large copper pad to the drill handle to couple the RF ground to the human torch holding it.. Sure, we’ve seen plenty of tesla lately, but who here wouldn’t want one? (Maybe the guy in the server room…)
All the parts needed are listed – just be sure you fully understand everything before you get into this one.
Back From Vegas Extra
I made it home after a long day of travel. Airport security let me through with my new home server – a 1U dual P3 800Mhz Compaq rackmount that I scored from the guys at UNIX surplus. Yes, it was my carry-on personal item.
Somehow I missed the MIDI tesla coil last month. Thanks to [skuhl] for sending it in. It’s a solid state coil that’s modulated to create one bad-ass midi box. The videos are worth checking out.
[martin] tells me that the Pentax k10d firmware has been hacked for polish menus. I’ll let you guys sort through it, I’m honestly too tired to deal with translating it right now.
[Alex] re-cased a macbook power supply to repair a slightly ripped out power cable. Those power supplies aren’t cheap, so it’s worth noting.
By the way, I’ve got one of the midnight research wicrawl CDs, so ask nice if you want me to put up a torrent.
Defcon 15: Exploiting Authentication Systems
[Zac Franken] gave a good talk on authentication systems. (Card readers, biometric systems, etc). After a good introduction to various access control systems, he demoed an excellent exploit tool. Rather than focus on the access mechanism, he exploited the lack of reader installation security. Most card readers are secured by a plastic cover and a pair of screws. Inside, the reader wires are vulnerable. [Zac] put together the equivalent of a keyboard sniffer for the reader wiring. With this little device in place, he was able to collect access codes and use them to exploit the reader authentication system.
The operation goes like this: Install the sniffer. Let it collect some codes. On return, [Zac] is able to use his own card to become a pseudo authenticated card owner, restrict and allow access to other cards. That’s it. No sneaking up behind people to read their cards, just a few minutes with a screwdriver.
He’s not releasing the design, simply because measures to prevent this type of intercept/control mechanism would be extremely costly.
Black Hat 2007 Premature AJAX-ulation
Billy Hoffman and Bryan Sullivan from SPI Dynamics gave one of the more entertaining talks today. The title is an allusion to peoples willingness to apply new technology before they fully understand it. Instead of laughing at silly web 2.0 developers they decided to build their own AJAXified website by consulting the resources that any programmer would: AJAX books, blogs, and forums. What they ended up with was hackervactations.com… a security hole riddled gem built on good intentions.
Black Hat 2007 No-Tech Hacking With Johnny Long
[J0hnny]’s at Blackhat and Defcon this year with his talk on “No-Tech Hacking”. It’s a fun talk that boils down to this: loads of information can be gathered using low tech methods. A small digital (or film) camera is ideal for shoulder surfing, identifying weaknesses, and assessing strengths.
The talk is pretty amusing – the commentary on the example shots is priceless. The concept has gone over so well at the cons that [J0hnny] has contributed a chapter to a book on risk management. You can grab a sample chapter here. It looks like he’ll be running his talk at 8pm on Friday at Defcon. From the sample chapter, I’d say that the book should be pretty good. It looks like a good introduction to social engineering and using your wits to defeat obstacles (like corporate security).
