Nerd Sport: Harddisk Speaker!

Everytime I think it could not be worse I am impressed and surprised that it can be. After the fabulous Harddisk VU-Meter built by reply2all there is another Harddisk-mod project: Harddisk Speaker.

The idea is: take a defect Harddisk. Modify the read/write head interface and it’s bearing, add a standard stereo jack: Voilà you have a Harddisk Speaker.

The (quiet) sound is made by the read/write head when it’s moved fast on the plate.

The stereo jack in my notebook…

Soldering No. 1

Soldering No. 2
(connects the head interface to the jumper pins)

Soldering No. 3
(the bearing modified to move better)

the opened drive…

Really impressive to see that that little bit of energy from the stereo jack is enough to make the read/write head move and even create a sound. You can really hear the music … louder than you would expect. Okay: Sound quality is improvable especially the lower frequencies.

Source: Harddisk VU-meter

RSA200 factored

Numbercruncing cereals!

"We have factored RSA200 by GNFS. The factors are




We did lattice sieving for most special q between 3e8 and 11e8
using mainly factor base bounds of 3e8 on the algebraic side and 18e7 
the rational side. The bounds for large primes were 2^35. This produced
26e8 relations. Together with 5e7 relations from line sieving the total
yield was 27e8 relations. After removing duplicates 226e7 relations
remained. A filter job produced a matrix with 64e6 rows and columns,
having 11e9 non-zero entries. This was solved by Block-Wiedemann.

Sieving has been done on a variety of machines. We estimate that
lattice sieving would have taken 55 years on a single 2.2 GHz Opteron 
Note that this number could have been improved if instead of the PIII-
binary which we used for sieving, we had used a version of the
lattice-siever optimized for Opteron CPU's which we developed in the 
The matrix step was performed on a cluster of 80 2.2 GHz Opterons 
connected via a Gigabit network and took about 3 months.

We started sieving shortly before Christmas 2003 and continued until
October 2004. The matrix step began in December 2004.
Line sieving was done by P. Montgomery and H. te Riele at the CWI, by
F. Bahr and his family."


ecki ecki ecki pateng! A desktop wiki

In the IRC channel I was asked by Marcus (the author of Moinx) to test if Moinx would run on Mac OSX Tiger. So I checked it. Marcus could not know that I was searching for something like this: A easy to install and manage Wiki.

Just download and drag the Moinx Icon to the application folder and you got a locally available Wiki. You can even configure it to be accessible via the network… great thing.


playing with the SONY HDR-FX1E

FeM e.V. bought one Sony HDR-FX1E. Beside the amazing specification that camera has it’s really fun to play with these … I don’t want to call them gadget … with these cameras. B-)

And some juicy facts:

“3 x 1/3in CCD with 1.12 Mpixels (1.07 Mpixels effective); HDV 1,080i recording (1,440 x 1,080 at 50 interlaced fields per second); DV recording; 16:9 DV recording; 16-bit and 12-bit PCM audio recording; f/1.6-2.8 lens with 12x optical zoom (4.5 – 54 mm, 35 mm equivalent 32.5 – 390 mm); optical image stabiliser and full-range autofocus; DV in/out; HDV in/out; S-video in/out; composite AV in/out; component A/V in/out; lens filter diameter, 72mm; 0.3in/252,000-pixel colour LCD viewfinder with dioptre adjuster; 3.5in/251,000-pixel colour LCD fully adjustable view panel.”

Source: Review of Sony HDR-FX1E