Hello,
You may be interest by this project from Tipok: http://tipok.org.ua/node/41
It's a simplified and low cost SDR transmission interface using an FX2 USB controller and an AD9957 modulator/DAC.
Here he's using it to create a DAB digital radio transmission using CRC mmbtools DAB multiplexer/modulator.
Mathias
opendigitalradio.org
Hi Hunz,
I've just pushed some updated code up to GitHub, you can now set the
gain in the preferences and tweak the scan settings. There's some info
at http://eartoearoak.com/software/rtlsdr-scanner#tweaking
A 250kHz offset seems to work well with my E4000, 140k with a FC0012 and
100k with a R820T. The FC0012 is the noisiest and the R820T is quietest.
Hope it helps,
Al
On 17/03/2013 11:00, Benedikt Heinz <zn000h(a)gmail.com> wrote:
>> For me the most interesting plots were the "no antenna" ones, showing the LO
>> leakage ;-) If I understood clearly your plots, you have at some places high
>> power ghosts. Maybe you are close to powerful transmitters, but this is more
>> probably a LO to RF isolation problem: the receiver receives himself...
> I did two new measurements with the gain set to 20 in RTLSDR-Scanner.
> The files with the -gain20 in the filename [1] show the new results.
> There are more spikes from the R820T LOs now, but it's still less than
> with the E4000 I'd say.
> The good thing is that the DVB-T stations as well as some other
> signals can be found as expected now.
>
> 2013/3/16 Al <al(a)eartoearoak.com>:
>> I think you've run into a couple of issues, firstly it appears that the AGC
>> isn't fully disabled on the R820T (if you remove the aerial the noise floor
>> increases).
> It looks like gain=0 just was too little for the R820T. gain=20 seems
> to be a good start.
> Maybe exposing the gain-value in the regular UI would make sense?
>
>> Secondly RTLSDR-Scanner averages 2 chunks of bandwidth either side of the DC
>> point, these seem relatively quiet with an E4000 and FC0012 but I haven't
>> had chance to check the R820T yet. This tuner may have a very different
>> noise floor. I was wondering about adding a feature to allow the user to
>> pick their own segments (by terminating the aerial and looking at the noise
>> distribution).
> Ah, that's interesting. I was indeed wondering how you avoid the DC
> spike and my pathon skills are close to zero ;-)
> According to [2], the R820T doesn't use a Zero-IF, so there should be
> no DC-spike at all.
>
>> Has anyone had a chance to test 2 different dongles with the same tuner?
>> I'd be interested to know if it makes a difference to the noise floor, if
>> there is little change, I could vary the scan based on the tuner.
> I do have two E4000 and two R820T dongles, but I haven't yet compared
> the noise floor.
> I'm thinking about a per-dongle baseline file w/o an antenna for
> compensation. This approach should be more robust. Otherwise you need
> to shift the baseline spectrum according to the frequency error.
>
> Best regards,
>
> Hunz
>
> [1] https://docs.google.com/folder/d/0ByDAKwyEiyx_XzZ5ZnpRV1VZWDQ/edit?usp=shar…
> [2] http://lists.osmocom.org/pipermail/osmocom-sdr/2012-September/000253.html
>
Hello,
I am using two of the "usual" RTL2832-USB dongles, with Ubuntu 12.04.
The one with the R820T tuner in it works with both GQRX and SDRSharp
(although driving the laptop temperature beyond 60°C - P-Mobile 1,8 GHz,
with SDRSharp/Mono only!).
The one with E4000 tuner is only accepted by GQRX. SDRSharp says "Array
index is out of range", although in the dropdown menu, for both dongles
"RTL-SDR / USB" is displayed.
Anyone got an idea ...?
Lorenz
Hey all,
Osmocom is such a great community with awesome projects. Why doesn't
Osmocom apply for GSOC 2013? It's a really nice opportunity.
- More students will come to know about osmocom thus greater visibility
- Some great minds will work on the projects so it may lead to something
more awesome
- Osmocom community will get to mentor students which is a very
important experience, because that is how one understands the problems of
new developers
Cheers,
*Hemant *
Hi,
it seems you've triggered an issue recently introduced via gnuradio master:
http://gnuradio.org/cgit/gnuradio.git/commit/?id=9297c84dfdae3002677f759ef2…
Their config.h basically overrides our build-time generated one which not
only effectively disables every single source functionality but also
causes the build error you experienced.
I've just pushed a small workaround for that, please test it & report.
One second issue i've noticed is that in your configuration every single
option seems to be enabled, although not all dependencies have been
detected. Usually a full configuration should look like in the attached
file.
Best regards,
Dimitri
I failed when I " make ".
the make error is :
/tmp/gr-osmosdr/lib/osmosdr_source_c_impl.cc: In constructor
‘osmosdr_source_c_impl::osmosdr_source_c_impl(const string&)’:
/tmp/gr-osmosdr/lib/osmosdr_source_c_impl.cc:117:16: error:
‘GR_OSMOSDR_VERSION’ was not declared in this scope
/tmp/gr-osmosdr/lib/osmosdr_source_c_impl.cc:117:47: error:
‘GR_OSMOSDR_LIBVER’ was not declared in this scope
make[2]: ***
[lib/CMakeFiles/gnuradio-osmosdr.dir/osmosdr_source_c_impl.cc.o] Error 1
make[1]: *** [lib/CMakeFiles/gnuradio-osmosdr.dir/all] Error 2
make: *** [all] Error 2
the cmake output is :
-- Build type not specified: defaulting to release.
-- Extracting version information from git describe...
-- Configuring Boost C++ Libraries...
-- checking for module 'gnuradio-iqbalance'
-- package 'gnuradio-iqbalance' not found
-- Found gnuradio-uhd: /usr/local/include,
/usr/local/lib/libgnuradio-uhd.so
-- Found gnuradio-fcd: /usr/local/include,
/usr/local/lib/libgnuradio-fcd.so
-- Will build with gnuradio iqbalance support.
--
-- The build system will automatically enable all components.
-- Use -DENABLE_DEFAULT=OFF to disable components by default.
--
-- Configuring sysmocom OsmoSDR support...
-- Dependency LIBOSMOSDR_FOUND = TRUE
-- Enabling sysmocom OsmoSDR support.
-- Override with -DENABLE_OSMOSDR=ON/OFF
--
-- Configuring FunCube Dongle support...
-- Dependency GNURADIO_FCD_FOUND = TRUE
-- Enabling FunCube Dongle support.
-- Override with -DENABLE_FCD=ON/OFF
--
-- Configuring IQ File Source support...
-- Dependency GNURADIO_CORE_FOUND = TRUE
-- Enabling IQ File Source support.
-- Override with -DENABLE_FILE=ON/OFF
--
-- Configuring Osmocom RTLSDR support...
-- Dependency LIBRTLSDR_FOUND = TRUE
-- Enabling Osmocom RTLSDR support.
-- Override with -DENABLE_RTL=ON/OFF
--
-- Configuring RTLSDR TCP Client support...
-- Dependency GNURADIO_CORE_FOUND = TRUE
-- Enabling RTLSDR TCP Client support.
-- Override with -DENABLE_RTL_TCP=ON/OFF
--
-- Configuring Ettus UHD support...
-- Dependency UHD_FOUND = TRUE
-- Dependency GNURADIO_UHD_FOUND = TRUE
-- Enabling Ettus UHD support.
-- Override with -DENABLE_UHD=ON/OFF
--
-- Configuring Osmocom MiriSDR support...
-- Dependency LIBMIRISDR_FOUND = TRUE
-- Enabling Osmocom MiriSDR support.
-- Override with -DENABLE_MIRI=ON/OFF
--
-- ######################################################
-- # gr-osmosdr enabled components
-- ######################################################
-- * sysmocom OsmoSDR
-- * FunCube Dongle
-- * IQ File Source
-- * Osmocom RTLSDR
-- * RTLSDR TCP Client
-- * Ettus UHD
-- * Osmocom MiriSDR
--
-- ######################################################
-- # gr-osmosdr disabled components
-- ######################################################
--
-- Building for version: 1eb3af22 / 0.0.1git
-- Using install prefix: /usr/local
-- Configuring done
-- Generating done
-- Build files have been written to: /tmp/gr-osmosdr/build
*
*
Hello,
I am running an RTL2832 USB stick (R820T tuner in it) and SDRSharp via
Mono under Ubuntu 12.04 with a Pentium-M 1.5GHz and 1,5 GB RAM.
SDRSharp
With sample rates of 0.25M and 1.024M, I'm "suffering" from 100% CPU
load and temperatures around 70°C - this can't be healthy for the
laptop... Switching the waterfall off and speed etc. to minimum doesn't
help very much. RDS is displayed fine, all functions seem to be OK. RAM
space is not filled up (30%).
Any advice for a "smoother" running on such an "old" machine...?
http://superkuh.com/rtlsdr.html#sdrsharpappnote said "it can even run on
my old 1.8Ghz P4 laptop".
GQRX
GQRX did run using the QtPro way as described in the wiki, but after
recent update of GQRX the DC spike at centre frequency appeared (it
wasn't there before), and massive stuttering of audio and the "OOOOOO"s
in terminal window at a lot of different sample rates made the usage of
GQRX worse. (right, this should be posted in a GQRX forum...)
Anyway, did someone notice that GQRX update (ca. first days of march
2013) lead to problems ?
thanks,
Lorenz
HI All !
Many thanks Salvatore for that very impressive piece of software.
I extended dump1090 to make use of a mysql database:
http://dl6kbg.blogspot.de/2013/03/dump1090-with-mysql-support.html
I will work on the code the next days to improve it for a more easy db
setup.
Some results and a description you may see here:
http://dl6kbg.blogspot.de/2013/03/dump1090-with-mysql-support.html
the forked repo is here:
https://github.com/dl6kbg/dump1090
You need a mysql database called "dump1090" with a table "tracks". You may
easily setup the db using the supplied script "tracks.sql"
Username and password ist coded for now as mysql user: root mysql password:
root.
Run: ./dump1090 --mysql
Have fun !
73 Oliver DL6KBG
Gird you Grid for the next level in Software Definition. We are now stuck in
Software Defined Radio (SDR). Next is Software Defined Instrumentation (SDI)
with intriguing choices like the Vector Signal Transceiver (VST) for Device
Testing.