--> ap/xxxxx

__

Logging code for scrying: (scrying_tech_notes#52)

http://1010.co.uk/serialtest.c

1] Logs 10 bit value from adc0 to SRAM

2] Prompt for the following commands on usart0 (ATmega128):

log: dump log to serial port

live: show live reading of ADC

num: show log counter

reset: reset log counter

3] Data dumped to file by way of minicom and graphed with Octave:

Software defined radio/ITC/Baudline notes and references: (2008.06.20:1 tech_notes2#40 scrying_tech_notes#51)

1] Building and testing GNU Radio (Debian testing):

svn co http://gnuradio.org/svn/gnuradio/trunk gnuradio

apt-get install libtool portaudio19-dev alsa-dev alsa-source python-wxgtk2.6 python-numpy

export PYTHONPATH=/usr/local/lib/python2.4/site-packages/

./bootstrap

./configure

make install

ldconfig

cd ~/gnuradio/gnuradio-examples/python/audio

./audio_fft.py -I hw:0,0 -S

References:

GNU Radio tutorials: http://www.nd.edu/~jnl/sdr/docs/tutorials/1.pdf

http://www.spectrum.ieee.org/oct06/4654/toolsb1

http://www.kd7lmo.net/ground_gnuradio.html

SDR: http://f4dan.free.fr/sdr_eng.html

2] Demodulation using Baudline:

Ref: http://www.domenech.org/homebrew-sdr/receiver-3.htm

http://www.baudline.com/manual/glossary.html

http://www.burtonmackenzie.com/2007/05/poor-mans-spectrum-analyzer.html

http://www.febo.com/pages/baudline/

Use of decimate and down-mixer:

Down-mixer allows us to move across frequency range down-sampling.

What is decimation?

"a technique for reducing the number of samples in a discrete-time signal."

Play deck window - advanced features: high pass and low pass filters, use of shift for demodulation.

3] ITC/EVP ref:

EM related: http://members.tripod.com/:/Article1.htm