diff options
Diffstat (limited to 'writeup/article.md')
| -rw-r--r-- | writeup/article.md | 183 |
1 files changed, 0 insertions, 183 deletions
diff --git a/writeup/article.md b/writeup/article.md deleted file mode 100644 index c198ecf..0000000 --- a/writeup/article.md +++ /dev/null @@ -1,183 +0,0 @@ -# RTLSDR usage - -# Index - - -1. Setup rtlsdr - 1.1. Get sources - 1.2. Drivers - 1.3. Check if works -2. Collection of tools - 2.1. FM - 2.2. Spectrum diagram - 2.3. ADSB - 2.4. AFSK1200 -3. Projects where rtlsdr used - 3.1. WebSDR -4. Problems - 4.1. Sync errors -5. Links -6. Changelog - - -## 1.Setup rtlsdr - - -By rtlsdr usually call RTL2832U chip based tv-tunners which -can be used for not just recievin DVB-T frequencies but much more -and yes price is ~$10 it mean that anyone can just buy and try -without "loosing" money. - - -### 1.1.Get sources - - -Main development repository is on http://sdr.osmocom.org/trac/wiki/rtl-sdr -on github you can find more repos with experminental -features (https://github.com/keenerd/rtl-sdr). - -Getting sources from git: -``` - git clone git://git.osmocom.org/rtl-sdr.git -``` -I prefer using plain binaries without any kind of installation. Just -compile and use binary without any troubles. -Build: -```bash - cmake . - make -``` -All binaries is in src dir - - -### 1.2.Drivers - - -Linux kernel have some drivers for rtlsdr stick and DVB-T. When you will plug -rtlsdr then kernel probably will load DVB-T drivers and you will not able -to use you rtlsdr for sdr. Way yo fix is it add some drivers to black list and -next time when you will plug rtlsdr this drivers will not be loaded. - -Check if rtlsdr related drivers is loaded: -```bash - lsmod | grep rtl28 -``` -If there is some drivers then balcklist driver by creating file -in */etc/modprobe.d/* with content: -``` - blacklist dvb_usb_rtl28xxu -``` -Next thing that could appear is permissions on rtlsdr usage when its pluged in. -To allow everyone to use create file in */etc/udev/rules.d/* with content: -``` - SUBSYSTEM=="usb", ATTRS{idVendor}=="0bda", ATTRS{idProduct}=="2838", \ - GROUP="adm", MODE="0666", SYMLINK+="rtl_sdr" -``` - -### 1.3.Check if works - -How to test if rtlsdr works? Run one of commands: - rtl_test - -I like to run rtl_adsb as you can see there that something is recieved and -you see that everything "works": - rtl_adsb - -There should be line by line showing up some "hex" lines. If some data is showen -then adsb data from plains is recieved. - -## 2.Collection of tools - - -### 2.1.FM - -Get some sound trancmited from FM radio stations. - -```bash - rtl_fm -f 96.3e6 -M wbfm -s 200000 -r 48000 - | aplay -r 48k -f S16_LE -``` - - -### 2.2.Spectrum diagram - -Scan spectrum to find some activities on different frequencies. -Good link with all description is http://kmkeen.com/rtl-power/ . -Main usage of rtl_power is : -```bash - rtl_power -f 76M:108M:125k -i 1 fm_stations.csv -``` -and then draw image : -```bash - heatmap.py fm_stations.csv fm_stations.png -``` - -### 2.3.ADSB - -ADS-B ( Automatic dependent surveillance broadcast ) in simple words airplain -geoposition, speed, height and flight number broadcasting. You can recieve -this data and see how many plains is around and sometimes flight number. - -rtlsdr have default one rtl_adsb programm but it shows only recieved data, -without any decoding. Here is dump1090 specifically for rtlsdr and nothing -more: - - https://github.com/antirez/dump1090 - -description howto install could be found also here - - http://www.satsignal.eu/raspberry-pi/dump1090.html - -Using in interactive mode with height in metrs: -```bash - dump1090 --interactive --metric -``` -Output: - -``` - Hex Flight Altitude Speed Lat Lon Track Messages Seen . - ------------------------------------------------------------------------------ - 71be01 10052 1009 36.434 33.544 45 9 1 sec - 424913 SDM6329 10966 711 36.440 33.405 221 65 0 sec -``` - - -### 2.4.AFSK1200 - -Gqrx is graphical SDR software where you can travel across frequencies -and in real time search for some transmission. - - http://gqrx.dk/ - -It have builtin AFSK1200 demodulator or in simple words ham radio packets. -And you could try to see what people sending in tex around the world. - -## 3.Projects where rtlsdr used - -### 3.1.WebSDR - -WebSDR probably best site where you can go and click on some radio reciever -and liste what happends in some particular country. WebSDR site contains -about 80 radio recievers around the world that can be accessed trought web -interface. - http://websdr.org/ - -If you whant setup your own radio reciever read FAQ, prepare mail and send mail -after that you could recieve precompiled websdr software with is easy -to setup with rtlsdr stick. - -## 4.Problems - -### 4.1.Sync errors - -Once there was sync error when was trying to use rtl_test or rtl_adsb. -To fix that changes for better quality usb cable. - -# 5.Links - -1. [http://kmkeen.com/rtl-demod-guide/](http://kmkeen.com/rtl-demod-guide/) -2. http://kmkeen.com/rtl-power/ -3. http://sdr.osmocom.org/trac/wiki/rtl-sdr -4. http://www.rtl-sdr.com/ -5. https://github.com/antirez/dump1090 -6. http://gqrx.dk - |