johannes raggam for radio helsinki

data radio, pt.4 is an experiment to transmit encoded digital data over a civil FM radio network. the sounds received can be decoded using special, freely available software or – if available – hardware devices. with the process of encoding digital data, transmitting it over terrestrial radio networks and decoding at endpoints an simple alternative to the network called internet is created.

in fact, such guerrilla networks were successfully created by different parties in crisis/war situations. for example, the serbian radio b92 used CB radio transmission for exchanging information with isolated parts of former yugoslavia.

listeners of radia.fm are encouraged to decode or record (for later decoding) the  data or just listen to the stream of fax noise.

for decoding, follow these instructions:

* install the software to decode the encoded data and configure it according to the settings explained below.

* connect the line-out of your stereo with the line-in of your computer.
alternatively, but trickier, redirect an internet audio stream to the decoding software.

“data radio” – in german “datenradio” – started as a project for the “netart community convention 2009″ in graz by johannes raggam in collaboration with christian pointner. for more information (in german) see [1][2].

Settings for HamFax on linux
—————————-
carrier     800Hz
deviation   400Hz
modulation  FM
filter      middle
lpm         200
color mode

Software for decoding
———————
linux
””’
HamFax: http://hamfax.sourceforge.net/

windows (untested)
”””””””””
MultiPSK: http://f6cte.free.fr/index_anglais.htm
MultiFAX: http://www.qsl.net/n2zde/index.html

OSX (untested)
”””””””
MultiMode: http://www.blackcatsystems.com/software/multimode.html

References
[1] https://wiki.mur.at/ncc09/DatenRadio
[2] http://ncc09.mur.at/doku/media.html

by Reni Hofmüller, Jogi Hofmüller, Katarina Petjovic and Borut Savski.

In November 1998, Reni and Jogi Hofmüller went to visit their friends, then living in Ljubljana, Katarina Pejovic and Borut Savski.
As they had all been involved in different ways in radio making, sound production, and experimenting, it was clear that – though there had not been the plan beforehand – they would go to Radio Student, to the Ministery of Experiment, and do precisely this: experiment.
In the case of the Grazer Walzer, the production idea was simple: we went to the radio music archive, and took out several lps and cds, and decided to play only the beginnings of songs. In radio history, very often the intros of songs have not been aired, as the BPM (beats-per-minute) did not fit the “overall sound of the station”. So in an somehwat “ausgleichende Gerechtigkeit” (“poetic justice”) we exclusively played intros, and combined them with lp-scretching, text created with the apple-error-messaging system and some additional sounds, produced with piezos and other microphones.
For radia, I compiled a 27 minutes version, taken from the original 1 hour piece.

Reni Hofmüller, 2010