Heard the newly launched Fox-1D satellite as it passed over Seattle just 20 minutes ago. About every 3 minutes, it transmitted “Fox 1 Delta, Safe Mode.” Can’t wait to catch the Virginia Tech camera images when that hardware is enabled again.
I have no Morse skillz (yet), but I managed to use my iPhone to capture the audio of the CW beacon of the XW-2A cubesat as it passed through the skies to the West of our home, loaded it into Audacity and looked at the waveform to find the signature “CAMSAT” word that the spacecraft includes in its CW transmission:
Too cool 🙂
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.
I’m making progress on the 440 MHz preamp kit. Should be up and running soon. Will make hearing the 70cm satellites a lot easier I hope. (The kit is by Ramsey, fancy aluminum case by Hammond.)
the demodulator you’ve been working on starts outputting meaningful data instead of gibberish (T7RPUR WIDE1 WIDE2 are valid packet radio strings).
I’m writing the demodulator in C++ and it uses the Goertzel algorithm. Need to continue to flesh out the framer, and hook up STDIN to accept sound from rtl_fm and my new SDR dongle.
The goal: automated reception of Space Station packet radio, powered by Raspberry Pi.
Just arrived in the mail today and, of course, it is for a space station contact.