Re: [Discuss-gnuradio] question regarding usrp_fft.py

2009-09-10 Thread Eric Blossom
On Thu, Sep 10, 2009 at 07:26:56PM -0700, adib_sairi wrote: > > besides my last two post (which unfortunately i still don't have any answer) > , i have another question.. any help will be very appreciated. > > > if we transmit using benchmark_tx.py, we can change the amplitude of the > transmiss

Re: [Discuss-gnuradio] question regarding usrp_fft.py

2009-09-10 Thread adib_sairi
besides my last two post (which unfortunately i still don't have any answer) , i have another question.. any help will be very appreciated. if we transmit using benchmark_tx.py, we can change the amplitude of the transmission by changing the --tx-Amplitude and this parameter max value is 9830.1

[Discuss-gnuradio] Questions regarding interpolator and usrp.sink_c configuration

2009-09-10 Thread Milo Wong
Hi All, Here I have a couple of questions during my project: 1, I am receiving "uU"(usrp underrun) when I am transmitting, it seems that the data rate I feed to DAC is less than 128MS/s? I've already set the maximum interpolation rate at 512. What's the problem might be? I guess the input dat

Re: [Discuss-gnuradio] Installation problem: Ubuntu 9.04-gnuradio binary 3.2 package (recursion depth error)

2009-09-10 Thread Eric Blossom
On Wed, Sep 09, 2009 at 10:30:16PM -0700, DDKK wrote: > > I am wondering if this is some kind of pythonpath setup error that I'm > making. > > I get the same error if I just import the gr definition from gnuradio in the > python interpreter. It gives me the same error message the first time, > a

Re: [Discuss-gnuradio] Latency measurement using GnuRadio

2009-09-10 Thread Ed Criscuolo
The short answer is, because our customers require it! The longer answer is that these are strictly low-earth-orbit spacecraft, communicating through a relay in geosync. So, the round-trip time is dominated by the round-trip time to geosync, which is around 250 mS. The new modems include all so

Re: [Discuss-gnuradio] message queue in grc

2009-09-10 Thread Eric Blossom
On Thu, Sep 10, 2009 at 12:13:21PM +0200, Dimitris Symeonidis wrote: > I have noticed that you can't add a message queue to a GRC flowgraph. Why is > that? Is the reason technical, or that no one bothered to write the .xml > file? > > And is the message queue going to be deprecated in gnuradio 3.3

Re: [Discuss-gnuradio] message queue in grc

2009-09-10 Thread Josh Blum
In the current master, there is a message source and message sink block in grc. And you can create custom blocks with ports of type "msg" and connect them! However, blocks with both a msg input AND a msg output are currently unsupported. Also, It should be noted that this functionality will li

Re: [Discuss-gnuradio] about RDS and FM transmission

2009-09-10 Thread Rafael Diniz
Thanks Dimitris! I'll run your code w/ my USRP, but I don't have enough knowledge to fix it. Please let me known when you finish the transmit path - I think there is no free radio in Brazil doing RDS. Rafael Diniz > Hi Rafael, I'm the current developer of GR-RDS. > > The RDS signal has to be mixe

[Discuss-gnuradio] Why is an FFT filter used in benchmark_receiver?

2009-09-10 Thread udadidd
Hi I found that an fft_filter is being used in the receiver! I did not understand its use though. Can anyone please help me in here? I am trying to transmit and receiver audio instead of usrp. How helpful is this filter in my case? Thanks Udaya -- View this message in context: http://www.nabbl

[Discuss-gnuradio] Latency measurement using GnuRadio

2009-09-10 Thread Ed Criscuolo
Hi all. At work we're building some new modems for spacecraft communication, and I've been tasked with coming up with a test set or tool for measuring latency through each side of the modem (modulator and demodulator). I'd like to use GnuRadio 2 and a USRP2 to do some or all of this. I was

[Discuss-gnuradio] message queue in grc

2009-09-10 Thread Dimitris Symeonidis
I have noticed that you can't add a message queue to a GRC flowgraph. Why is that? Is the reason technical, or that no one bothered to write the .xml file? And is the message queue going to be deprecated in gnuradio 3.3? Thank you Dimitris Symeonidis "If you think you're too small to make a diff

Re: [Discuss-gnuradio] about RDS and FM transmission

2009-09-10 Thread Dimitris Symeonidis
Hi Rafael, I'm the current developer of GR-RDS. The RDS signal has to be mixed with the mono, pilot tone and stereo signals BEFORE fm modulation. Also, be aware that the transmit path is not working yet, I'm debugging it when I have some spare time to fix it. Any help is welcome. You should use

Re: [Discuss-gnuradio] Re: Some questions about audio output and under-runs on a custom block....

2009-09-10 Thread Steve Glass
Eric Just a quick thank you for your help. I had only a fuzzy idea about how forecast works and your explanation that audio_sink is rate-limiting meant it fell into place. I still use throttle to limit the input rate from file because (like you) I am using GUI elements at several stages in the pr