# GNU Radio **URL:** https://www.ruby-forum.com/c/gnu-radio/15.md?page=60 [Latest](https://www.ruby-forum.com/latest.md) · [Categories](https://www.ruby-forum.com/categories.md) · [Tags](https://www.ruby-forum.com/tags.md) **Page:** 61 --- ## [Can't find qtgui](https://www.ruby-forum.com/t/cant-find-qtgui/231181)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 0\ **Last updated:** [July 25, 2014, 2:46pm UTC](https://www.ruby-forum.com/t/cant-find-qtgui/231181 "2014-07-25T14:46:28Z")
HI all, I am very, very new to gnuradio and am trying to get this to run on Windows 7 (yes, I haven’t given up yet). When I try to load gnuradio.qtgui I get the following reply… runfile(‘C:/Users/Chriss\_2/GnuRadio\_S… --- ## [Gnuradio dataflow, buffering and scheduling](https://www.ruby-forum.com/t/gnuradio-dataflow-buffering-and-scheduling/231128)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 10\ **Last updated:** [July 25, 2014, 12:31pm UTC](https://www.ruby-forum.com/t/gnuradio-dataflow-buffering-and-scheduling/231128 "2014-07-25T12:31:40Z")
Dear all, I wish to study how gnuradio handles the dataflow,e.g., buffering, scheduling, synchronization, optimization as well as resultant latency in detail. However, I can not find any material that explain such th… --- ## [Re: Error in OP25 Decoder block](https://www.ruby-forum.com/t/re-error-in-op25-decoder-block/231174)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 0\ **Last updated:** [July 25, 2014, 3:32am UTC](https://www.ruby-forum.com/t/re-error-in-op25-decoder-block/231174 "2014-07-25T03:32:27Z")
Hi Doug It appears that more extensive changes (than just the tiny patch I sent yesterday) would be needed to gz-baz to make it compatible with the latest (3.7) versions of GR and of op25. Also (AFAIK) there is no su… --- ## [Hierarchical blocks (arbitrary or variable numbers of inputs or outputs not supported)](https://www.ruby-forum.com/t/hierarchical-blocks-arbitrary-or-variable-numbers-of-inputs-or-outputs-not-supported/231168)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 1\ **Last updated:** [July 24, 2014, 10:13pm UTC](https://www.ruby-forum.com/t/hierarchical-blocks-arbitrary-or-variable-numbers-of-inputs-or-outputs-not-supported/231168 "2014-07-24T22:13:46Z")
Hello, I am trying to create a hierarchical block with a variable number of outputs, but I get this error: “RuntimeError: Hierarchical blocks do not yet support arbitrary or variable numbers of inputs or outputs” Th… --- ## [Undefined reference error](https://www.ruby-forum.com/t/undefined-reference-error/231164)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 3\ **Last updated:** [July 24, 2014, 4:40pm UTC](https://www.ruby-forum.com/t/undefined-reference-error/231164 "2014-07-24T16:40:09Z")
Hi there, I’m run into a linker error when I build my OOT module; Hereafter what I get when typing sudo make: \* libgnuradio-ssg.so: undefined reference to « gr::filter::firdes::window(gr::filter::firdes::win\_type, … --- ## [802.11a preamble format](https://www.ruby-forum.com/t/802-11a-preamble-format/231155)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 0\ **Last updated:** [July 24, 2014, 10:08am UTC](https://www.ruby-forum.com/t/802-11a-preamble-format/231155 "2014-07-24T10:08:21Z")
Hi all, I want to use the 802.11a preamble format but don’t know if it’s available in GNUradio? Greetings, Van-Ly Nguyen Van-Ly, Vietnam National University, Hanoi - VNU University of Engineering and Technology -… --- ## [QAM Mod / Demod blocks](https://www.ruby-forum.com/t/qam-mod-demod-blocks/231142)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 2\ **Last updated:** [July 24, 2014, 5:45am UTC](https://www.ruby-forum.com/t/qam-mod-demod-blocks/231142 "2014-07-24T05:45:04Z")
Discuss-gnuradio mailing list removed\_email\_address@domain.invalid https://lists.gnu.org/mailman/listinfo/discuss-gnuradio --- ## [UDP Network?](https://www.ruby-forum.com/t/udp-network/231150)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 3\ **Last updated:** [July 23, 2014, 8:23pm UTC](https://www.ruby-forum.com/t/udp-network/231150 "2014-07-23T20:23:26Z")
Hey everyone, I’m currently trying to send the same generated signal from two usrp’s to a third usrp/host. On the transmitting side, I can clearly see both signals going out, but on the receiving side, I am getting a … --- ## [USRP N210 Clock generation](https://www.ruby-forum.com/t/usrp-n210-clock-generation/231144)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 1\ **Last updated:** [July 23, 2014, 8:08pm UTC](https://www.ruby-forum.com/t/usrp-n210-clock-generation/231144 "2014-07-23T20:08:11Z")
Discuss-gnuradio mailing list removed\_email\_address@domain.invalid https://lists.gnu.org/mailman/listinfo/discuss-gnuradio --- ## [ImportError: No module named](https://www.ruby-forum.com/t/importerror-no-module-named/231136)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 7\ **Last updated:** [July 23, 2014, 5:05pm UTC](https://www.ruby-forum.com/t/importerror-no-module-named/231136 "2014-07-23T17:05:08Z")
Hi all, I have created a new module called Tool\_NetworkCoding. During the installation, I did not get any error message, everything went well. But when I run a grc file to test some blocks inside this new module, it … --- ## [Message passing - issue with messages left in queues after running top block](https://www.ruby-forum.com/t/message-passing-issue-with-messages-left-in-queues-after-running-top-block/231120)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 1\ **Last updated:** [July 23, 2014, 3:50pm UTC](https://www.ruby-forum.com/t/message-passing-issue-with-messages-left-in-queues-after-running-top-block/231120 "2014-07-23T15:50:24Z")
Hi all, I’ve noticed that “Run to completion” works now in situation when message passing is used, which is great! I have a related question. I’m creating a block which uses message passing, and run it once: tb … --- ## [Filter design](https://www.ruby-forum.com/t/filter-design/231139)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 2\ **Last updated:** [July 23, 2014, 3:48pm UTC](https://www.ruby-forum.com/t/filter-design/231139 "2014-07-23T15:48:12Z")
Hello, GNURadio offers three different interfaces to design filters from Python code: gnuradio.filter.firdes.xxx, gnuradio.filter.firdes.xxx\_2, and gnuradio.filter.optfir.xxx. The three interfaces use different param… --- ## [Beamforming with GNU Radio and USRPs](https://www.ruby-forum.com/t/beamforming-with-gnu-radio-and-usrps/231140)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 3\ **Last updated:** [July 23, 2014, 2:50pm UTC](https://www.ruby-forum.com/t/beamforming-with-gnu-radio-and-usrps/231140 "2014-07-23T14:50:10Z")
Hi everyone, I am currently trying to get 2 N210 to transmit coherently to a third N210. All devices have GPSDO kits and the “gps\_locked” status is on “locked”, there is no MIMO cable in the setup. I am currently do… --- ## [PyBombs install maint branch from fresh](https://www.ruby-forum.com/t/pybombs-install-maint-branch-from-fresh/231131)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 11\ **Last updated:** [July 23, 2014, 2:47pm UTC](https://www.ruby-forum.com/t/pybombs-install-maint-branch-from-fresh/231131 "2014-07-23T14:47:12Z")
Dear Sirs, I am performing fresh gnuradio installation using pybombs. Pybombs install master branch by default. How to make pybombs install ‘maint’ instead? Act@rsLAPTOP: ~/download/pybombs $ git checkout maint erro… --- ## [How to uninstall an OUT-OF-TREE module?](https://www.ruby-forum.com/t/how-to-uninstall-an-out-of-tree-module/231132)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 1\ **Last updated:** [July 23, 2014, 11:14am UTC](https://www.ruby-forum.com/t/how-to-uninstall-an-out-of-tree-module/231132 "2014-07-23T11:14:21Z")
Hi all, I have made an OUT-OF-TREE module, but now I want to remove it from gnuradio. I am using GNUradio 3.7.3. Can anyone tell me how to that? Thanks a lot Van-Ly Nguyen Van-Ly, Vietnam National University, Hanoi… --- ## [Synchronizing N210 TX and RX channels](https://www.ruby-forum.com/t/synchronizing-n210-tx-and-rx-channels/231127)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 11\ **Last updated:** [July 23, 2014, 10:45am UTC](https://www.ruby-forum.com/t/synchronizing-n210-tx-and-rx-channels/231127 "2014-07-23T10:45:34Z")
Hello, I would like to synchronize the RX and TX channels on an N210 so that the acquisition and transmission of data are triggered simultaneously. I haven’t found documentation on how to do that. Can someone, please, … --- ## [Libboost error](https://www.ruby-forum.com/t/libboost-error/231093)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 5\ **Last updated:** [July 23, 2014, 6:25am UTC](https://www.ruby-forum.com/t/libboost-error/231093 "2014-07-23T06:25:18Z")
Dear all, I’m installing GNU Radio 3.7.3 on Ubuntu 14.04. When I run “make”, I got this error: \[ 86%\] Built target gnuradio-uhd /usr/local/lib/libuhd.so, not found (try using -rpath or -rpath-link) boost::re\_detail… --- ## [Cross-correlating Two FFT signals](https://www.ruby-forum.com/t/cross-correlating-two-fft-signals/231123)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 3\ **Last updated:** [July 22, 2014, 7:38pm UTC](https://www.ruby-forum.com/t/cross-correlating-two-fft-signals/231123 "2014-07-22T19:38:22Z")
Hello, I’m trying to find a way that I could cross-correlate two FFT signals that I have coming in from two UDP networks, anyone know of a block I can do that with? Thanks in advance, Marcus --- ## [Tx-power usrp n210 and wbx doughterboard](https://www.ruby-forum.com/t/tx-power-usrp-n210-and-wbx-doughterboard/231116)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 3\ **Last updated:** [July 22, 2014, 4:26pm UTC](https://www.ruby-forum.com/t/tx-power-usrp-n210-and-wbx-doughterboard/231116 "2014-07-22T16:26:04Z")
Hi at all, I have problem to understand how an USRP used as a trasmitter works in term of transmitted power when we fix a tx\_gain. Let me explain better: The WBX Daughterboard is a wide bandwidth transceiver that p… --- ## [How does Packet Header Generator module handle tags](https://www.ruby-forum.com/t/how-does-packet-header-generator-module-handle-tags/231081)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 7\ **Last updated:** [July 22, 2014, 10:52am UTC](https://www.ruby-forum.com/t/how-does-packet-header-generator-module-handle-tags/231081 "2014-07-22T10:52:55Z")
Hi Experts, I was reading tx\_ofdm.py. I found this module use ‘set\_tag\_propagation\_policy(TPP\_DONT)’ to handle tags by itself, but I cann’t find the code that used to handle tag in this module. I knew this module wil… --- ## [Gain Calibration for WX FFT](https://www.ruby-forum.com/t/gain-calibration-for-wx-fft/231105)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 0\ **Last updated:** [July 21, 2014, 9:46pm UTC](https://www.ruby-forum.com/t/gain-calibration-for-wx-fft/231105 "2014-07-21T21:46:24Z")
Hello All, I am using the USRP B210 to analyze the signal spectrum. I have configured it to have a 30 MHz bandwidth and the signal looks pretty clean. I am trying to get the GUI to present the same signal levels as t… --- ## [Implementing callbacks in custom blocks](https://www.ruby-forum.com/t/implementing-callbacks-in-custom-blocks/231079)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 4\ **Last updated:** [July 21, 2014, 6:06pm UTC](https://www.ruby-forum.com/t/implementing-callbacks-in-custom-blocks/231079 "2014-07-21T18:06:58Z")
Using gr\_modtool, I am trying to make a simple Gain block (called var\_gain) which multiplies the input with a constant. I have a private variable called d\_gain in the var\_gain\_impl class and a public function set\_gai… --- ## [Re: Error in OP25 Decoder block](https://www.ruby-forum.com/t/re-error-in-op25-decoder-block/231059)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 1\ **Last updated:** [July 18, 2014, 7:53pm UTC](https://www.ruby-forum.com/t/re-error-in-op25-decoder-block/231059 "2014-07-18T19:53:22Z")
import op25 I got the prompt right back, no error message. Right - pretty much as expected. This strongly suggests that the python code you’re attempting to use (in this case, from gr-baz) has not yet been f… --- ## [Re: Error in OP25 Decoder block](https://www.ruby-forum.com/t/re-error-in-op25-decoder-block/231060)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 0\ **Last updated:** [July 18, 2014, 6:37pm UTC](https://www.ruby-forum.com/t/re-error-in-op25-decoder-block/231060 "2014-07-18T18:37:37Z")
Max - import op25 I got the prompt right back, no error message. I haven’t tried your other suggestion yet. Doug from gnuradio import gr, gru, op25 as \_op25 ImportError: cannot import name op25 . . . . Y… --- ## [Demodulating digital signal (FSK?) from audio](https://www.ruby-forum.com/t/demodulating-digital-signal-fsk-from-audio/230992)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 8\ **Last updated:** [July 18, 2014, 6:18pm UTC](https://www.ruby-forum.com/t/demodulating-digital-signal-fsk-from-audio/230992 "2014-07-18T18:18:42Z")
Hello, I would like to write an application that checks the battery status of wireless microphones. The battery status is transmitted as a very low frequency (below 10 Hz) signal that is mixed in the normal audio. I w… --- ## [Re: Error in OP25 Decode block](https://www.ruby-forum.com/t/re-error-in-op25-decode-block/231056)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 2\ **Last updated:** [July 18, 2014, 5:54pm UTC](https://www.ruby-forum.com/t/re-error-in-op25-decode-block/231056 "2014-07-18T17:54:50Z")
I built it with Pybombs. I just installed gr-baz. I didn’t know there was a way to install op25 decoder separately. I would like to know how to install the GNURadio 3.7.4 just announced. Doug On Fri, Jul 18, 2014… --- ## [Removing gnuradio 3.6 and reinstalling 3.7 with build-gnu radio](https://www.ruby-forum.com/t/removing-gnuradio-3-6-and-reinstalling-3-7-with-build-gnu-radio/230948)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 1\ **Last updated:** [July 18, 2014, 5:54pm UTC](https://www.ruby-forum.com/t/removing-gnuradio-3-6-and-reinstalling-3-7-with-build-gnu-radio/230948 "2014-07-18T17:54:08Z")
I have a system that is remotely deployed. I have ssh access to the machine and some limited Vnc. I do not have physical access to do a fresh OS install. In looking at my install, it looks like I got 3.6 for most stuf… --- ## [Pybomb gnuradio installation doesn't install gr-uhd](https://www.ruby-forum.com/t/pybomb-gnuradio-installation-doesnt-install-gr-uhd/234804)
**Author:** [@alcina](https://www.ruby-forum.com/u/alcina)\ **Replies:** 8\ **Last updated:** [July 18, 2014, 5:50pm UTC](https://www.ruby-forum.com/t/pybomb-gnuradio-installation-doesnt-install-gr-uhd/234804 "2014-07-18T17:50:38Z")
I just installed gnuradio and uhd via pybomb, sourced the env file in the prefix dir, and attempted to do “from gnuradio import uhd”. gnuradio imports and inspection shows it’s the prefixed version, but uhd fails with… --- ## [Re: Error in OP25 Decoder block](https://www.ruby-forum.com/t/re-error-in-op25-decoder-block/231058)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 0\ **Last updated:** [July 18, 2014, 5:37pm UTC](https://www.ruby-forum.com/t/re-error-in-op25-decoder-block/231058 "2014-07-18T17:37:18Z")
Doug One thing you could try is to make the following change in gr-baz python/op25.py - YMMV. Max diff --git a/python/op25.py b/python/op25.py index 19669da…d45d794 100644 — a/python/op25.py +++ b/python/op25.py … --- ## [Re: Error in OP25 Decoder block](https://www.ruby-forum.com/t/re-error-in-op25-decoder-block/231057)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 0\ **Last updated:** [July 18, 2014, 5:23pm UTC](https://www.ruby-forum.com/t/re-error-in-op25-decoder-block/231057 "2014-07-18T17:23:55Z")
from gnuradio import gr, gru, op25 as \_op25 ImportError: cannot import name op25 It’s slightly challenging to attempt remote diagnosis of this type of issue; at first glance I thought this might just be an easy one … [Previous page](https://www.ruby-forum.com/c/gnu-radio/15.md?page=59) [Next page](https://www.ruby-forum.com/c/gnu-radio/15.md?page=61)