# GNU Radio **URL:** https://www.ruby-forum.com/c/gnu-radio/15.md?page=47 [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:** 48 --- ## [Comparator block?](https://www.ruby-forum.com/t/comparator-block/232728)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 2\ **Last updated:** [October 28, 2014, 5:56pm UTC](https://www.ruby-forum.com/t/comparator-block/232728 "2014-10-28T17:56:26Z")
Hi, I would like to have a comparator in my GRC block design to compair something like SNR or RMS or both on RX channels in my design. Logic would be something like… if channel A\>B then switch to channel B else use c… --- ## [Rational\_resampler vs pfb\_arb\_resampler filter design -- why such strange cut frequencies in both ca](https://www.ruby-forum.com/t/rational-resampler-vs-pfb-arb-resampler-filter-design-why-such-strange-cut-frequencies-in-both-ca/232697)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 2\ **Last updated:** [October 28, 2014, 1:02pm UTC](https://www.ruby-forum.com/t/rational-resampler-vs-pfb-arb-resampler-filter-design-why-such-strange-cut-frequencies-in-both-ca/232697 "2014-10-28T13:02:36Z")
\-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 I’m looking at filter design procedures for rational\_resampler and pfb\_arb\_ resampler and see contradiction between them. Lets assume downsample with rate 3/4 or 0.75. … --- ## [Compiling SWIG python bindings with -builtin option](https://www.ruby-forum.com/t/compiling-swig-python-bindings-with-builtin-option/232548)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 11\ **Last updated:** [October 28, 2014, 12:16pm UTC](https://www.ruby-forum.com/t/compiling-swig-python-bindings-with-builtin-option/232548 "2014-10-28T12:16:38Z")
Hello, I use the vector\_source\_x and vector\_sinc\_x blocks quite a lot for testing, debugging and simulations, even with quite large input and output data streams. Therefore I was looking in speeding up the feeding an… --- ## [Python ./top\_block.py error](https://www.ruby-forum.com/t/python-top-block-py-error/232767)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 0\ **Last updated:** [October 27, 2014, 9:51am UTC](https://www.ruby-forum.com/t/python-top-block-py-error/232767 "2014-10-27T09:51:46Z")
Hi, I get this error when trying to run python ./top\_block.py python ./top\_block.py Traceback (most recent call last): File “./top\_block.py”, line 8, in from gnuradio import analog ImportError: No module named gnur… --- ## [Out of tree modules?](https://www.ruby-forum.com/t/out-of-tree-modules/232754)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 0\ **Last updated:** [October 26, 2014, 4:07pm UTC](https://www.ruby-forum.com/t/out-of-tree-modules/232754 "2014-10-26T16:07:58Z")
reading about out-of-tree-modules here http://gnuradio.org/redmine/projects/gnuradio/wiki/OutOfTreeModules Theres a ref to Cgran website for out-of-tree-modules etc but the site is dead! https://www.cgran.org/ anyone… --- ## [Some block not avaiable](https://www.ruby-forum.com/t/some-block-not-avaiable/232753)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 0\ **Last updated:** [October 26, 2014, 11:15am UTC](https://www.ruby-forum.com/t/some-block-not-avaiable/232753 "2014-10-26T11:15:41Z")
Hi there,i installed gnuradio and i do some tutorial ,but in my gnuradio(install in software center)misssing block variable slider.I checked in the install folder and saw the file VariableSlider.xml but it not appear … --- ## [\[Help\] install gnuradio from source (follow youtube guide video)](https://www.ruby-forum.com/t/help-install-gnuradio-from-source-follow-youtube-guide-video/232750)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 0\ **Last updated:** [October 26, 2014, 7:35am UTC](https://www.ruby-forum.com/t/help-install-gnuradio-from-source-follow-youtube-guide-video/232750 "2014-10-26T07:35:14Z")
Hi all,i try to install gnuradio follow this video GNURADIO installation from source part-7 (setting python path, installing gnuradio-companion) - YouTube but in step 7 : /\* tomcang@ubuntu:~$ sudo apt-get install gnur… --- ## [Multi thread fft execution](https://www.ruby-forum.com/t/multi-thread-fft-execution/232743)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 5\ **Last updated:** [October 26, 2014, 6:17am UTC](https://www.ruby-forum.com/t/multi-thread-fft-execution/232743 "2014-10-26T06:17:32Z")
Hi all, I have the following c++ code which gets fft by sliding on sample by sample fo the input. /\* \* The private constructor \*/ sliding\_fft\_impl::sliding\_fft\_impl(uint fft\_size) : gr::sync\_block("sliding\_ff… --- ## [What does "Feedback" mean in the issue tracker?](https://www.ruby-forum.com/t/what-does-feedback-mean-in-the-issue-tracker/232740)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 2\ **Last updated:** [October 25, 2014, 4:57pm UTC](https://www.ruby-forum.com/t/what-does-feedback-mean-in-the-issue-tracker/232740 "2014-10-25T16:57:16Z")
What does it mean in the GNU Radio issue tracker for an issue to have the status “Feedback”? Two of my bugs have been in this state and I don’t know what this means about them. I thought it might mean “asking for repo… --- ## [Dwell Delay and Tune Delay](https://www.ruby-forum.com/t/dwell-delay-and-tune-delay/227496)
**Author:** [@Nada\_ABDELKADER](https://www.ruby-forum.com/u/Nada_ABDELKADER)\ **Replies:** 1\ **Last updated:** [October 25, 2014, 12:28pm UTC](https://www.ruby-forum.com/t/dwell-delay-and-tune-delay/227496 "2014-10-25T12:28:30Z")
Hi How to adjust the dwell and tune delays and the FFT\_size for spectrum sensing? Are they related to h/w properties or just a choice for experimentation? Nada --- ## [PSK demodulation of a sub-carrier sent over FM](https://www.ruby-forum.com/t/psk-demodulation-of-a-sub-carrier-sent-over-fm/232690)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 4\ **Last updated:** [October 24, 2014, 12:14pm UTC](https://www.ruby-forum.com/t/psk-demodulation-of-a-sub-carrier-sent-over-fm/232690 "2014-10-24T12:14:50Z")
Hello, I had experimented with simple PSK reception with GNU-Radio when the carrier is directly phase modulated. However I would like to know how can I demodulate a PSK transmission which is carried over a typical F… --- ## [Fwd: out-of-tree module config.h documentation/use](https://www.ruby-forum.com/t/fwd-out-of-tree-module-config-h-documentation-use/232729)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 1\ **Last updated:** [October 24, 2014, 12:10pm UTC](https://www.ruby-forum.com/t/fwd-out-of-tree-module-config-h-documentation-use/232729 "2014-10-24T12:10:05Z")
Hi I am writing an out-of-tree module and have used the gr\_modtool to generate the module and block skeletons. All the block source files include a config.h file, but I have not been able to find documentation of its… --- ## [Phase change for Transmitted Signal Bursts - The relation to clock?](https://www.ruby-forum.com/t/phase-change-for-transmitted-signal-bursts-the-relation-to-clock/246012)
**Author:** [@Rafa\_F](https://www.ruby-forum.com/u/Rafa_F)\ **Replies:** 2\ **Last updated:** [October 23, 2014, 8:02pm UTC](https://www.ruby-forum.com/t/phase-change-for-transmitted-signal-bursts-the-relation-to-clock/246012 "2014-10-23T20:02:00Z")
Hi, I am transmitting a series of BPSK burst signal and try to observe the phase distortion for the BPSK signal on air. But it is found that the Phases of different BPSK bursts are different. I think this change is c… --- ## [Pybombs?](https://www.ruby-forum.com/t/pybombs/232715)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 2\ **Last updated:** [October 23, 2014, 7:56pm UTC](https://www.ruby-forum.com/t/pybombs/232715 "2014-10-23T19:56:03Z")
Hi, I wanted to do a quick and dirty gnuradio install with pybombs, and all looked fine, built uhd and gnuradio and what else is included in the default, but it seems it did not add any paths and such. Is this possib… --- ## [Tx-gain in gr-digital/ofdm/example/benchmark\_tx.py](https://www.ruby-forum.com/t/tx-gain-in-gr-digital-ofdm-example-benchmark-tx-py/232722)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 0\ **Last updated:** [October 23, 2014, 6:20pm UTC](https://www.ruby-forum.com/t/tx-gain-in-gr-digital-ofdm-example-benchmark-tx-py/232722 "2014-10-23T18:20:30Z")
Hi Does anyone here know what is the transmission power for USRP N210? I searched the datasheet, it seems the maximum is about 20 dbm. But when I run the code in gr-digital/ofdm/example/benchmark\_tx.py, the tx-gain r… --- ## [Building a Zedboard BOOT.bin](https://www.ruby-forum.com/t/building-a-zedboard-boot-bin/232717)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 2\ **Last updated:** [October 23, 2014, 5:36pm UTC](https://www.ruby-forum.com/t/building-a-zedboard-boot-bin/232717 "2014-10-23T17:36:12Z")
Hi, I am trying to generate a bootable SD card for the zedboard and I am running over some small issues. For starters, do you provide the u-boot.elf you use somewhere? In the http://gnuradio.org/data/sdk/zedboard\_ar… --- ## [Free shipping for GNU Radio gear!](https://www.ruby-forum.com/t/free-shipping-for-gnu-radio-gear/232720)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 1\ **Last updated:** [October 23, 2014, 5:20pm UTC](https://www.ruby-forum.com/t/free-shipping-for-gnu-radio-gear/232720 "2014-10-23T17:20:44Z")
I’ve just been informed that the store we use for GNU Radio merchandise (in the US) is having free shipping next week on orders of $30 or more. Check out our store: http://gnuradio.spreadshirt.com/ And if you see an… --- ## [Get a pointer to UHD "Source" from other block in flow graph](https://www.ruby-forum.com/t/get-a-pointer-to-uhd-source-from-other-block-in-flow-graph/232721)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 0\ **Last updated:** [October 23, 2014, 4:45pm UTC](https://www.ruby-forum.com/t/get-a-pointer-to-uhd-source-from-other-block-in-flow-graph/232721 "2014-10-23T16:45:02Z")
How to get a UHD USRP SOURCE OBJECT within my own block ? I already instantiate an UHD USRP SOURCE in the flowgraph and I want a pointer within my own block to read parameters. Also, which is the effect of creating t… --- ## [Feedback loop for bpsk carrier recovery?](https://www.ruby-forum.com/t/feedback-loop-for-bpsk-carrier-recovery/232711)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 1\ **Last updated:** [October 23, 2014, 3:53pm UTC](https://www.ruby-forum.com/t/feedback-loop-for-bpsk-carrier-recovery/232711 "2014-10-23T15:53:14Z")
For educational purposes, I am investigating a carrier recovery scheme for BPSK demodulation. I have synthesized a BPSK modulated signal, assembled a hardware carrier recovery scheme which works well (squaring the mo… --- ## [Installing GNU Radio](https://www.ruby-forum.com/t/installing-gnu-radio/232696)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 5\ **Last updated:** [October 23, 2014, 3:12pm UTC](https://www.ruby-forum.com/t/installing-gnu-radio/232696 "2014-10-23T15:12:10Z")
Hello Everyone, I hate asking questions like this, but I need help installing GNU Radio. The objective is to have GNU Radio 3.7.5.1 and UHD installed on Ubuntu 14.04 so I can use it with my USRP N210. The problem I ha… --- ## [Transmitting bursts with GRC by inserting SOB and EOB](https://www.ruby-forum.com/t/transmitting-bursts-with-grc-by-inserting-sob-and-eob/232649)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 19\ **Last updated:** [October 23, 2014, 2:32pm UTC](https://www.ruby-forum.com/t/transmitting-bursts-with-grc-by-inserting-sob-and-eob/232649 "2014-10-23T14:32:18Z")
Hello, I am trying to implement a burst transmitter using GNU Radio Companion and an USRP N210 with WBX board. My problem is when inserting zeros as “gap” between the bursts the USRP is transmitting a non-neglectable … --- ## [\[coproc\] WG call next week](https://www.ruby-forum.com/t/coproc-wg-call-next-week/232701)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 0\ **Last updated:** [October 23, 2014, 3:36am UTC](https://www.ruby-forum.com/t/coproc-wg-call-next-week/232701 "2014-10-23T03:36:32Z")
I am scheduling the next Co-Processors WG call to take place next Wednesday, October 29, 2014 @ 2:00pm US/Eastern time (6:00pm UTC). I’ll send out a reminder next week. Currently there is no agenda, so if you plan on… --- ## [PyBOMBS GUI Bug?](https://www.ruby-forum.com/t/pybombs-gui-bug/232698)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 2\ **Last updated:** [October 22, 2014, 11:48pm UTC](https://www.ruby-forum.com/t/pybombs-gui-bug/232698 "2014-10-22T23:48:09Z")
Hello, I just installed PyBOMBS on Ubuntu 14.04. I’m noticing that sometimes the icon labels are readable, but a lot of them are off the screen and can’t be selected, like UHD. The last icon available to install for… --- ## [GNU Radio in Python Tutorial - installing python block without C++](https://www.ruby-forum.com/t/gnu-radio-in-python-tutorial-installing-python-block-without-c/232668)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 3\ **Last updated:** [October 22, 2014, 6:53pm UTC](https://www.ruby-forum.com/t/gnu-radio-in-python-tutorial-installing-python-block-without-c/232668 "2014-10-22T18:53:32Z")
Hi all, I’ve been going through the tutorials with a fresh install of GNURadio (Version 3.7.2.1) through Ubuntu’s package manager (Ubuntu 14.04) and I’ve run into a few issues when attempting to install a python bloc… --- ## [How to save bit stream?](https://www.ruby-forum.com/t/how-to-save-bit-stream/232686)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 2\ **Last updated:** [October 22, 2014, 5:23pm UTC](https://www.ruby-forum.com/t/how-to-save-bit-stream/232686 "2014-10-22T17:23:41Z")
Discuss-gnuradio mailing list removed\_email\_address@domain.invalid https://lists.gnu.org/mailman/listinfo/discuss-gnuradio --- ## [Iir\_filter does not work with specified feedback taps?](https://www.ruby-forum.com/t/iir-filter-does-not-work-with-specified-feedback-taps/232678)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 1\ **Last updated:** [October 22, 2014, 3:14pm UTC](https://www.ruby-forum.com/t/iir-filter-does-not-work-with-specified-feedback-taps/232678 "2014-10-22T15:14:33Z")
Hi All, Any guys who ever used IIR filters? I got problems as below: I want the IIR filter works as: y\[n\] = 1.8x\[n\] + 0.8y\[n-1\] Then I set the feed forward taps as \[1.8\], feeback taps as \[0.8\], just like self.iir\_f… --- ## [Guided Tutorials - Experience](https://www.ruby-forum.com/t/guided-tutorials-experience/232647)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 4\ **Last updated:** [October 22, 2014, 12:16pm UTC](https://www.ruby-forum.com/t/guided-tutorials-experience/232647 "2014-10-22T12:16:36Z")
Hello, I did 2 of the Guided Tutorials - Programming GNU Radio in Python and C++ and want to tell you about my experiences. First thanks for making this tutorials! They really help me to get a good start with GNU Rad… --- ## [Scaling down IFFT values](https://www.ruby-forum.com/t/scaling-down-ifft-values/232574)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 5\ **Last updated:** [October 22, 2014, 11:13am UTC](https://www.ruby-forum.com/t/scaling-down-ifft-values/232574 "2014-10-22T11:13:31Z")
Hi All, I need to scale down the OFDM transmission signal in time domain, after IFFT is done, so that, all the values are within the range -1 to 1. But, I cant simply add one more “scaling” block after cp\_adder in s… --- ## [WiMAX scanner](https://www.ruby-forum.com/t/wimax-scanner/232682)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 1\ **Last updated:** [October 22, 2014, 11:09am UTC](https://www.ruby-forum.com/t/wimax-scanner/232682 "2014-10-22T11:09:21Z")
Hello, I am interested in WiMAX technology (802.16e). In my research I am dealing with algorithms for admission control in Matlab. Typically these algorithms are located “within base station” – although they are not … --- ## [AtributeError with OOT Module](https://www.ruby-forum.com/t/atributeerror-with-oot-module/232684)
**Author:** [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Replies:** 0\ **Last updated:** [October 22, 2014, 10:58am UTC](https://www.ruby-forum.com/t/atributeerror-with-oot-module/232684 "2014-10-22T10:58:38Z")
Hello I am trying to install an OOT module into my GNURadio distribution. I can integrate the module into GRC and use it in the flowgraph. However, when I try to execute, I get the following Error: Traceback (most re… [Previous page](https://www.ruby-forum.com/c/gnu-radio/15.md?page=46) [Next page](https://www.ruby-forum.com/c/gnu-radio/15.md?page=48)