# GNU Radio **URL:** https://www.ruby-forum.com/c/gnu-radio/15.md?page=12 [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:** 13 --- ## [Usrp b210 gpio](https://www.ruby-forum.com/t/usrp-b210-gpio/242893)
**Author:** [@Sadaf\_N](https://www.ruby-forum.com/u/Sadaf_N)\ **Replies:** 6\ **Last updated:** [August 6, 2015, 8:59pm UTC](https://www.ruby-forum.com/t/usrp-b210-gpio/242893 "2015-08-06T20:59:50Z")
Hi, I want to control an antenna multiplxer via J504 gpio port. Actually I want to have logic 1 and logic 0 in order to switch the multiplxer. But it is difficult to find gpio example for B210. I have new version of … --- ## [Problem with streamed tags](https://www.ruby-forum.com/t/problem-with-streamed-tags/242885)
**Author:** [@Sadaf\_N](https://www.ruby-forum.com/u/Sadaf_N)\ **Replies:** 4\ **Last updated:** [August 6, 2015, 8:46pm UTC](https://www.ruby-forum.com/t/problem-with-streamed-tags/242885 "2015-08-06T20:46:24Z")
hi all, I have three blocks: MESSAGE\_LOADER reads a binary file and outputs it byte by byte to the next block (PACKET\_CREATOR). On every 28th byte (and on the 0th byte) it adds tags denoting the start of a PDU P… --- ## [Re: FEC GnuRadio 3.7.8rc1 Error](https://www.ruby-forum.com/t/re-fec-gnuradio-3-7-8rc1-error/242897)
**Author:** [@Rafa\_F](https://www.ruby-forum.com/u/Rafa_F)\ **Replies:** 1\ **Last updated:** [August 6, 2015, 7:15pm UTC](https://www.ruby-forum.com/t/re-fec-gnuradio-3-7-8rc1-error/242897 "2015-08-06T19:15:15Z")
On Thu, Aug 6, 2015 at 12:44 AM, Tom R. removed\_email\_address@domain.invalid wrote: … The problem isn’t with the GUI sinks; you can replace them with null sinks Tom, Thanks for the update. Which block exactly is c… --- ## [Re: gr-perf-monitorx Error](https://www.ruby-forum.com/t/re-gr-perf-monitorx-error/242896)
**Author:** [@Rafa\_F](https://www.ruby-forum.com/u/Rafa_F)\ **Replies:** 1\ **Last updated:** [August 6, 2015, 3:37pm UTC](https://www.ruby-forum.com/t/re-gr-perf-monitorx-error/242896 "2015-08-06T15:37:55Z")
On Wed, Aug 5, 2015 at 6:44 PM, Tom R. removed\_email\_address@domain.invalid wrote: \[PerfCounters\] ControlPort Monitor running. “/usr/local/lib/python2.7/dist-packages/gnuradio/ctrlport/GNURadioControlPortClient.py… --- ## [Channel Model](https://www.ruby-forum.com/t/channel-model/242889)
**Author:** [@Sadaf\_N](https://www.ruby-forum.com/u/Sadaf_N)\ **Replies:** 10\ **Last updated:** [August 6, 2015, 11:58am UTC](https://www.ruby-forum.com/t/channel-model/242889 "2015-08-06T11:58:49Z")
Hii I am using channels.channel\_model as channels\_channel\_model\_0 = channels.channel\_model( noise\_voltage = self.EbN0\_to\_noise\_voltage(EbN0), frequency\_offset=0.0, epsilon=1.0, taps=(1.0 + 0j, ), noise\_seed=RAND\_S… --- ## [Pybombs difficulty](https://www.ruby-forum.com/t/pybombs-difficulty/242866)
**Author:** [@Rafa\_F](https://www.ruby-forum.com/u/Rafa_F)\ **Replies:** 8\ **Last updated:** [August 6, 2015, 3:03am UTC](https://www.ruby-forum.com/t/pybombs-difficulty/242866 "2015-08-06T03:03:42Z")
I use gentoo at home and have no difficulty keeping gnuradio up to date. At work we’re on a standalone network (no internet) so occasionally bring computers home to update them. Lately, I’ve been having trouble with … --- ## [How to choose tune\_delay?](https://www.ruby-forum.com/t/how-to-choose-tune-delay/242854)
**Author:** [@Rafa\_F](https://www.ruby-forum.com/u/Rafa_F)\ **Replies:** 4\ **Last updated:** [August 6, 2015, 2:47am UTC](https://www.ruby-forum.com/t/how-to-choose-tune-delay/242854 "2015-08-06T02:47:56Z")
Hi all, I want to retune the frequency of my USRP in Python during runtime. I understand from usrp\_spectrum\_sense.py that I can just retune the USRP during runtime, and that I need to allow for some tune\_delay to make … --- ## [GLError 1285](https://www.ruby-forum.com/t/glerror-1285/242864)
**Author:** [@Rafa\_F](https://www.ruby-forum.com/u/Rafa_F)\ **Replies:** 3\ **Last updated:** [August 6, 2015, 12:18am UTC](https://www.ruby-forum.com/t/glerror-1285/242864 "2015-08-06T00:18:58Z")
I have users of my simple\_ra application complaining of this: Traceback (most recent call last): File “/usr/local/lib64/python2.7/site-packages/gnuradio/wxgui/plotter/plotter\_base.py”, line 209, in \_on\_paint for fcn… --- ## [FEC GnuRadio 3.7.8rc1 Error](https://www.ruby-forum.com/t/fec-gnuradio-3-7-8rc1-error/242884)
**Author:** [@Sadaf\_N](https://www.ruby-forum.com/u/Sadaf_N)\ **Replies:** 1\ **Last updated:** [August 5, 2015, 9:45pm UTC](https://www.ruby-forum.com/t/fec-gnuradio-3-7-8rc1-error/242884 "2015-08-05T21:45:19Z")
Ubuntu 14.04 64-bit Gnuradio 3.7.8rc1 I am running this flowgraph “fecapi\_async\_to\_stream.grc” that comes with gr-fec. After running for a while following error always show up … … DEBUG: 16384, 560, 272 DEBUG: 163… --- ## [GRCon15\> Registration Updates](https://www.ruby-forum.com/t/grcon15-registration-updates/242891)
**Author:** [@Rafa\_F](https://www.ruby-forum.com/u/Rafa_F)\ **Replies:** 0\ **Last updated:** [August 5, 2015, 5:04pm UTC](https://www.ruby-forum.com/t/grcon15-registration-updates/242891 "2015-08-05T17:04:20Z")
We’re heading into the final weeks before GRCon15, and registration has thus far been strong. The new developers day and the main conference are about 2/3 sold, which still leaves plenty of tickets. The RFNoC tutorial … --- ## [Python keep running](https://www.ruby-forum.com/t/python-keep-running/242877)
**Author:** [@Sadaf\_N](https://www.ruby-forum.com/u/Sadaf_N)\ **Replies:** 1\ **Last updated:** [August 5, 2015, 4:42pm UTC](https://www.ruby-forum.com/t/python-keep-running/242877 "2015-08-05T16:42:08Z")
I have a GRC file that brings up a QT spectrum. I run grcc to create top\_block.py and then run python on the top\_block.py. When I click the close icon in the upper right corner of the spectrum window, the window goes … --- ## [Re: ControlPort 3.7.8rc1](https://www.ruby-forum.com/t/re-controlport-3-7-8rc1/242882)
**Author:** [@Sadaf\_N](https://www.ruby-forum.com/u/Sadaf_N)\ **Replies:** 1\ **Last updated:** [August 5, 2015, 3:47pm UTC](https://www.ruby-forum.com/t/re-controlport-3-7-8rc1/242882 "2015-08-05T15:47:48Z")
Inspecting GNU Radio Applications with ControlPort and Performance Gnuradio enabled component shows page linked above is from our weekly development builds. ControlPort is written in python ? When I ran qa\_ctrl… --- ## [Gr-perf-monitorx Error](https://www.ruby-forum.com/t/gr-perf-monitorx-error/242887)
**Author:** [@Sadaf\_N](https://www.ruby-forum.com/u/Sadaf_N)\ **Replies:** 1\ **Last updated:** [August 5, 2015, 3:46pm UTC](https://www.ruby-forum.com/t/gr-perf-monitorx-error/242887 "2015-08-05T15:46:38Z")
I am here again. I ran “fecapi\_async\_decoders.grc” with controlport performance moniter on. I made a new config.conf file in ~/.gnuradio and added following lines to it \[ControlPort\] on = True edges\_list = True \[P… --- ## [Cannot import name GNURadio when launching perf-monitorx and ctrlport-monitor](https://www.ruby-forum.com/t/cannot-import-name-gnuradio-when-launching-perf-monitorx-and-ctrlport-monitor/242840)
**Author:** [@Sadaf\_N](https://www.ruby-forum.com/u/Sadaf_N)\ **Replies:** 4\ **Last updated:** [August 5, 2015, 8:17am UTC](https://www.ruby-forum.com/t/cannot-import-name-gnuradio-when-launching-perf-monitorx-and-ctrlport-monitor/242840 "2015-08-05T08:17:24Z")
I am trying to measure performance of my OOT module with performance counter and control port. When I execute a command line gr-perf-monitorx or gr-ctrlport-monitor, an error below occurred: File “/usr/local/li… --- ## [Re: GRC FFT Plot](https://www.ruby-forum.com/t/re-grc-fft-plot/242879)
**Author:** [@Sadaf\_N](https://www.ruby-forum.com/u/Sadaf_N)\ **Replies:** 1\ **Last updated:** [August 4, 2015, 7:26pm UTC](https://www.ruby-forum.com/t/re-grc-fft-plot/242879 "2015-08-04T19:26:52Z")
Actually, you were right at first madengr. My transmitter is USRP1 with WBX 50-2200 while my receiver is USRP N200 with TVRX2 and spectrum analyzer. Can you give me suggestions on how I can match the amplitude on both… --- ## [Understanding decimator block](https://www.ruby-forum.com/t/understanding-decimator-block/242858)
**Author:** [@Rafa\_F](https://www.ruby-forum.com/u/Rafa_F)\ **Replies:** 1\ **Last updated:** [August 4, 2015, 4:40pm UTC](https://www.ruby-forum.com/t/understanding-decimator-block/242858 "2015-08-04T16:40:21Z")
Discuss-gnuradio mailing list removed\_email\_address@domain.invalid https://lists.gnu.org/mailman/listinfo/discuss-gnuradio --- ## [ControlPort 3.7.8rc1](https://www.ruby-forum.com/t/controlport-3-7-8rc1/242872)
**Author:** [@Rafa\_F](https://www.ruby-forum.com/u/Rafa_F)\ **Replies:** 3\ **Last updated:** [August 4, 2015, 4:29pm UTC](https://www.ruby-forum.com/t/controlport-3-7-8rc1/242872 "2015-08-04T16:29:50Z")
Ubuntu 14.04 64-bit I just installed frest gnuradio 3.7.8rc1 with control port enabled. I fetched gnuradio using git clone --recursive GitHub - gnuradio/gnuradio: GNU Radio – the Free and Open Software Radio Ecosystem … --- ## [Strange behaviour](https://www.ruby-forum.com/t/strange-behaviour/242875)
**Author:** [@Sadaf\_N](https://www.ruby-forum.com/u/Sadaf_N)\ **Replies:** 1\ **Last updated:** [August 4, 2015, 3:22pm UTC](https://www.ruby-forum.com/t/strange-behaviour/242875 "2015-08-04T15:22:39Z")
Hi, I’m seeing some strange behaviour in Gnuradio that i cannot explain. Subtracting the same value from each other should return zero, If I’m not mistaken. And why is there a dip in the center of my X310 stream? No … --- ## [TX and RX synchronization to control latency](https://www.ruby-forum.com/t/tx-and-rx-synchronization-to-control-latency/242876)
**Author:** [@Sadaf\_N](https://www.ruby-forum.com/u/Sadaf_N)\ **Replies:** 0\ **Last updated:** [August 4, 2015, 2:44pm UTC](https://www.ruby-forum.com/t/tx-and-rx-synchronization-to-control-latency/242876 "2015-08-04T14:44:40Z")
Hello, the recommended way to control latency due to buffers both in software and hardware is to synchronize the TX and RX streams, namely to have a mechanism that emits samples only when samples are received, minus a … --- ## [Pybombs with latest gnuradio 3.7.8. version](https://www.ruby-forum.com/t/pybombs-with-latest-gnuradio-3-7-8-version/242874)
**Author:** [@Rafa\_F](https://www.ruby-forum.com/u/Rafa_F)\ **Replies:** 1\ **Last updated:** [August 4, 2015, 2:20pm UTC](https://www.ruby-forum.com/t/pybombs-with-latest-gnuradio-3-7-8-version/242874 "2015-08-04T14:20:07Z")
Would be nice to see the latest gnuradio version 3.7.8 also available on pybombs. Currently there is 3.7.7.1-204 which I have just fetched from there. I would appreciate a response from anyone knowing more about it. B… --- ## [Trouble creating simple custom Sink (Python): Unable to coerce endpoint](https://www.ruby-forum.com/t/trouble-creating-simple-custom-sink-python-unable-to-coerce-endpoint/242863)
**Author:** [@Rafa\_F](https://www.ruby-forum.com/u/Rafa_F)\ **Replies:** 2\ **Last updated:** [August 4, 2015, 3:41am UTC](https://www.ruby-forum.com/t/trouble-creating-simple-custom-sink-python-unable-to-coerce-endpoint/242863 "2015-08-04T03:41:37Z")
I’d like to implement a simple custom sink block in Python. AFAIK, a sink is a 1:0 basic block, with one input port, and no output port. I define it as a class: class MySink(gr.basic\_block): def init(self, src\_block… --- ## [State Machine that drops samples (Problems with return and consume\_each in general\_work)](https://www.ruby-forum.com/t/state-machine-that-drops-samples-problems-with-return-and-consume-each-in-general-work/242865)
**Author:** [@Rafa\_F](https://www.ruby-forum.com/u/Rafa_F)\ **Replies:** 1\ **Last updated:** [August 3, 2015, 10:25pm UTC](https://www.ruby-forum.com/t/state-machine-that-drops-samples-problems-with-return-and-consume-each-in-general-work/242865 "2015-08-03T22:25:00Z")
Dear all, I’m trying to implement a simple state machine to receive bursty data and write it in a file. To accomplish this I have created a general block that accepts complex samples and has two states: 0 - Just dr… --- ## [Request regarding Channel Estimator Block](https://www.ruby-forum.com/t/request-regarding-channel-estimator-block/242848)
**Author:** [@Sadaf\_N](https://www.ruby-forum.com/u/Sadaf_N)\ **Replies:** 1\ **Last updated:** [August 3, 2015, 6:59pm UTC](https://www.ruby-forum.com/t/request-regarding-channel-estimator-block/242848 "2015-08-03T18:59:22Z")
Hello, I am unable to understand the max-carr-offset parameter in \*Channel Estimator block. \*How this parameter help in order to receive packets correctly in OFDM. What is the relation between this parameter and Freq… --- ## [Free IEEE tutorial](https://www.ruby-forum.com/t/free-ieee-tutorial/242862)
**Author:** [@Rafa\_F](https://www.ruby-forum.com/u/Rafa_F)\ **Replies:** 0\ **Last updated:** [August 3, 2015, 6:43pm UTC](https://www.ruby-forum.com/t/free-ieee-tutorial/242862 "2015-08-03T18:43:36Z")
Below is a free (to IEEE members) tutorial on wide bandwidth signal analysis. Let me know If you guys consider this kind of thing spam and but me being curious always appreciate a few diversions from time to time. We… --- ## [GRC FFT Plot](https://www.ruby-forum.com/t/grc-fft-plot/242860)
**Author:** [@Rafa\_F](https://www.ruby-forum.com/u/Rafa_F)\ **Replies:** 3\ **Last updated:** [August 3, 2015, 6:43pm UTC](https://www.ruby-forum.com/t/grc-fft-plot/242860 "2015-08-03T18:43:01Z")
Hi guys, I transmitted this -30 dB signal (Image 1) using a usrp: The spectrum analyzer displays -50 dBm (Image 2) as its reading. My receiver end picked up the signal with the same peak power at -30 dB (Image 3). I’… --- ## [Blocks handling vectors](https://www.ruby-forum.com/t/blocks-handling-vectors/242856)
**Author:** [@Sadaf\_N](https://www.ruby-forum.com/u/Sadaf_N)\ **Replies:** 1\ **Last updated:** [August 3, 2015, 6:38pm UTC](https://www.ruby-forum.com/t/blocks-handling-vectors/242856 "2015-08-03T18:38:55Z")
Hi, I have been struggling a bit trying to code a block that accept for example vectors of sync\_len\*sizeof(float) as input signature and outputs vectors of (sync\_len+pkt\_len)\*sizeof(float) as output signature. To unde… --- ## [FFT plot unit](https://www.ruby-forum.com/t/fft-plot-unit/242859)
**Author:** [@Rafa\_F](https://www.ruby-forum.com/u/Rafa_F)\ **Replies:** 7\ **Last updated:** [August 3, 2015, 6:36pm UTC](https://www.ruby-forum.com/t/fft-plot-unit/242859 "2015-08-03T18:36:35Z")
I was able to gather results, and I am really confused with it. I generated a -30 dB signal based on the fft plot shown and transmitted it using a usrp. My spectrum analyzer received a signal at -50 dBm (-80 dB) and m… --- ## [Solved! Repeat Block/New Repeat Block](https://www.ruby-forum.com/t/solved-repeat-block-new-repeat-block/242849)
**Author:** [@Sadaf\_N](https://www.ruby-forum.com/u/Sadaf_N)\ **Replies:** 4\ **Last updated:** [August 3, 2015, 9:47am UTC](https://www.ruby-forum.com/t/solved-repeat-block-new-repeat-block/242849 "2015-08-03T09:47:17Z")
Hi All: My previous report of lock-up issues with both the standard Repeat block, and a new OOT block that I wrote to allow variable interpolation can be ignored. The issue that generated my report was my use of a du… --- ## [USRP B210 TX gain](https://www.ruby-forum.com/t/usrp-b210-tx-gain/242850)
**Author:** [@Sadaf\_N](https://www.ruby-forum.com/u/Sadaf_N)\ **Replies:** 2\ **Last updated:** [August 3, 2015, 9:23am UTC](https://www.ruby-forum.com/t/usrp-b210-tx-gain/242850 "2015-08-03T09:23:54Z")
Hi, I am confused with 89dB tx gain of USRP B210 and what is the meaning of 89dB gain? How this value relates to maximum output of 50mW in B210? Because this value is too much high, as a example: If the RF output pow… --- ## [Block for Doppler shift correction](https://www.ruby-forum.com/t/block-for-doppler-shift-correction/242841)
**Author:** [@Sadaf\_N](https://www.ruby-forum.com/u/Sadaf_N)\ **Replies:** 2\ **Last updated:** [August 2, 2015, 4:28am UTC](https://www.ruby-forum.com/t/block-for-doppler-shift-correction/242841 "2015-08-02T04:28:13Z")
Hi, I’ve recently needed to correct some satellite signals for Doppler shift. I found that there was no easy way to do this yet - so I’ve created a small block that takes the Doppler shift information from Gpredict a… [Previous page](https://www.ruby-forum.com/c/gnu-radio/15.md?page=11) [Next page](https://www.ruby-forum.com/c/gnu-radio/15.md?page=13)