X-Git-Url: https://pere.pagekite.me/gitweb/homepage.git/blobdiff_plain/4dbf754e634282c21b8c45b4e93d7b607de390ab..1f2c8c10c70107880aa68eb15bc0e371854c745f:/blog/index.rss diff --git a/blog/index.rss b/blog/index.rss index fd5b2b1f88..32ebaa35cd 100644 --- a/blog/index.rss +++ b/blog/index.rss @@ -6,6 +6,73 @@ https://people.skolelinux.org/pere/blog/ + + rtlsdr-scanner, software defined radio frequency scanner for Linux - nice free software + https://people.skolelinux.org/pere/blog/rtlsdr_scanner__software_defined_radio_frequency_scanner_for_Linux____nice_free_software.html + https://people.skolelinux.org/pere/blog/rtlsdr_scanner__software_defined_radio_frequency_scanner_for_Linux____nice_free_software.html + Tue, 7 Mar 2023 23:10:00 +0100 + <p>Today I finally found time to track down a useful radio frequency +scanner for my software defined radio. Just for fun I tried to locate +the radios used in the areas, and a good start would be to scan all +the frequencies to see what is in use. I've tried to find a useful +program earlier, but ran out of time before I managed to find a useful +tool. This time I was more successful, and after a few false leads I +found a description of +<a href="https://www.kali.org/tools/rtlsdr-scanner/">rtlsdr-scanner +over at the Kali site</a>, and was able to track down +<a href="https://gitlab.com/kalilinux/packages/rtlsdr-scanner.git">the +Kali package git repository</a> to build a deb package for the +scanner. Sadly the package is missing from the Debian project itself, +at least in Debian Bullseye. Two runtime dependencies, +<a href="https://gitlab.com/kalilinux/packages/python-visvis.git">python-visvis</a> +and +<a href="https://gitlab.com/kalilinux/packages/python-rtlsdr.git">python-rtlsdr</a> +had to be built and installed separately. Luckily '<tt>gbp +buildpackage</tt>' handled them just fine and no further packages had +to be manually built. The end result worked out of the box after +installation.</p> + +<p>My initial scans for FM channels worked just fine, so I knew the +scanner was functioning. But when I tried to scan every frequency +from 100 to 1000 MHz, the program stopped unexpectedly near the +completion. After some debugging I discovered USB software radio I +used rejected frequencies above 948 MHz, triggering a unreported +exception breaking the scan. Changing the scan to end at 957 worked +better. I similarly found the lower limit to be around 15, and ended +up with the following full scan:</p> + +<p><a href="https://people.skolelinux.org/pere/blog/images/2023-04-07-radio-freq-scanning.png"><img src="https://people.skolelinux.org/pere/blog/images/2023-04-07-radio-freq-scanning.png" width="100%"></a></p> + +<p>Saving the scan did not work, but exporting it as a CSV file worked +just fine. I ended up with around 477k CVS lines with dB level for +the given frequency.</p> + +<p>The save failure seem to be a missing UTF-8 encoding issue in the +python code. Will see if I can find time to send a patch +<a href="https://github.com/CdeMills/RTLSDR-Scanner/">upstream</a> +later to fix this exception:</p> + +<pre> +Traceback (most recent call last): + File "/usr/lib/python3/dist-packages/rtlsdr_scanner/main_window.py", line 485, in __on_save + save_plot(fullName, self.scanInfo, self.spectrum, self.locations) + File "/usr/lib/python3/dist-packages/rtlsdr_scanner/file.py", line 408, in save_plot + handle.write(json.dumps(data, indent=4)) +TypeError: a bytes-like object is required, not 'str' +Traceback (most recent call last): + File "/usr/lib/python3/dist-packages/rtlsdr_scanner/main_window.py", line 485, in __on_save + save_plot(fullName, self.scanInfo, self.spectrum, self.locations) + File "/usr/lib/python3/dist-packages/rtlsdr_scanner/file.py", line 408, in save_plot + handle.write(json.dumps(data, indent=4)) +TypeError: a bytes-like object is required, not 'str' +</pre> + +<p>As usual, if you use Bitcoin and want to show your support of my +activities, please send Bitcoin donations to my address +<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p> + + + OpenSnitch available in Debian Sid and Bookworm https://people.skolelinux.org/pere/blog/OpenSnitch_available_in_Debian_Sid_and_Bookworm.html @@ -638,34 +705,6 @@ worked out.</p> would like to give more visibility. I'll stop here to avoid delaying this post.</p> -<p>As usual, if you use Bitcoin and want to show your support of my -activities, please send Bitcoin donations to my address -<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p> - - - - - LinuxCNC translators life just got a bit easier - https://people.skolelinux.org/pere/blog/LinuxCNC_translators_life_just_got_a_bit_easier.html - https://people.skolelinux.org/pere/blog/LinuxCNC_translators_life_just_got_a_bit_easier.html - Fri, 3 Jun 2022 21:10:00 +0200 - <p>Back in oktober last year, when I started looking at the -<a href="https://en.wikipedia.org/wiki/LinuxCNC">LinuxCNC</a> system, I -proposed to change the documentation build system make life easier for -translators. The original system consisted of independently written -documentation files for each language, with no automated way to track -changes done in other translations and no help for the translators to -know how much was left to translated. By using -<a href="https://po4a.org/">the po4a system</a> to generate POT and PO -files from the English documentation, this can be improved. A small -team of LinuxCNC contributors got together and today our labour -finally payed off. Since a few hours ago, it is now possible to -translate <a href="https://hosted.weblate.org/projects/linuxcnc/">the -LinuxCNC documentation on Weblate</a>, alongside the program itself.</p> - -<p>The effort to migrate the documentation to use po4a has been both -slow and frustrating. I am very happy we finally made it.</p> - <p>As usual, if you use Bitcoin and want to show your support of my activities, please send Bitcoin donations to my address <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>