Raspberry Pi + RTL-SDR Working

First, I used parts of this gist by floehopper to set up rtl-sdr utilities on the Raspberry Pi (already running Raspbian with a 8 GB flash card at its disposal):

pi@raspberrypi ~ $ sudo apt-get update
pi@raspberrypi ~ $ sudo apt-get upgrade
pi@raspberrypi ~ $ vi no-rtl.conf

blacklist dvb_usb_rtl28xxu
blacklist rtl2832
blacklist rtl2830

pi@raspberrypi ~ $ sudo mv no-rtl.conf /etc/modprobe.d/

pi@raspberrypi ~ $ sudo apt-get install git-core
pi@raspberrypi ~ $ sudo apt-get install git
pi@raspberrypi ~ $ sudo apt-get install cmake
pi@raspberrypi ~ $ sudo apt-get install libusb-1.0-0-dev
pi@raspberrypi ~ $ sudo apt-get install build-essential

pi@raspberrypi ~ $ git clone git://git.osmocom.org/rtl-sdr.git
pi@raspberrypi ~ $ cd rtl-sdr/
pi@raspberrypi ~/rtl-sdr $ mkdir build
pi@raspberrypi ~/rtl-sdr $ cd build
pi@raspberrypi ~/rtl-sdr/build $ cmake ../ -DINSTALL_UDEV_RULES=ON
pi@raspberrypi ~/rtl-sdr/build $ make
pi@raspberrypi ~/rtl-sdr/build $ sudo make install
pi@raspberrypi ~/rtl-sdr/build $ sudo ldconfig
pi@raspberrypi ~/rtl-sdr/build $ cd ~
pi@raspberrypi ~ $ sudo cp ./rtl-sdr/rtl-sdr.rules /etc/udev/rules.d/
pi@raspberrypi ~ $ sudo reboot

Then, I added sox (to get the play command):

pi@raspberrypi ~ $ sudo apt-get install sox libsox-fmt-all

I hooked up a speaker to the Raspberry Pi audio port and then tuned and listened to Puget Sound’s favorite packet frequency:

rtl_fm -f 144390000 -M fm -s 12k - | play -r 12k -t s16 -L -c 1 -

Worked nicely. Need to add squelch argument and combine this with the demodulator I’ve been working on.  Satellite tracking with automatic recording of space station packets is the ultimate goal.

No Space Station for You… Today

After an exciting week in Rome, I was even more excited about the Slow Scan Television transmissions from the International Space Station planned for this weekend. But turns out, there are no times where the Space Station is visible from the Seattle area that correspond with the broadcast times. So, Sad Christmas.

This sort of thing – having an easy, tightly integrated way to be able to know in advance of upcoming radio events for satellites which will be visible from your location – is exactly the sort of thing I think we need more of – to encourage our youth to look to the stars and take the next leaps – back to the Moon, to Asteroids, to Mars and beyond.

I’m working on an iOS app to do exactly that – make it easy to know when space based radio events are upcoming, with a user interface designed for teenagers and up. And, it will be open source. Things like this are worth sharing.