[Discuss-gnuradio] /dev/parport0: No such device or address
Hey, can anyone shed some light on this? I can do air captures to file and then listen to them, but I cannot listen to the signal live. The first time I tried it I followed the instructions in the error about making a /dev/parport0 to no effect. ./wfm_rcv.py 31.3e6 audio: using audio_alsa usrp: found usrp rev2 /dev/parport0: No such device or address terminate called after throwing an instance of 'std::runtime_error' what(): open Aborted thanks. also... '31.3e6' is Radio2 here in the UK on 89.8MHz. Is there an easy way to convert ddc into the actual freq? = mj - m0mik hotstudent.com [are you hot enough?!] __ Do you Yahoo!? Read only the mail you want - Yahoo! Mail SpamGuard. http://promotions.yahoo.com/new_mail ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] /dev/parport0: No such device or address
thanks chuck. all sorted now. mj --- Chuck Swiger <[EMAIL PROTECTED]> wrote: > At 01:57 AM 2/16/2005 -0800, you wrote: > >Hey, can anyone shed some light on this? I can do > air > >captures to file and then listen to them, but I > cannot > >listen to the signal live. The first time I tried > it I > >followed the instructions in the error about making > a > >/dev/parport0 to no effect. > > > >./wfm_rcv.py 31.3e6 > >audio: using audio_alsa > >usrp: found usrp rev2 > >/dev/parport0: No such device or address > >terminate called after throwing an instance of > >'std::runtime_error' > > what(): open > >Aborted > > > >thanks. > > > >also... '31.3e6' is Radio2 here in the UK on > 89.8MHz. > >Is there an easy way to convert ddc into the actual > >freq? > > > > Comment out the part near 'connect to rf front end' > that's trying > to talk to a gr.microtune_4937_eval_board () thru > the parallel board. > Change to: IF_Freq = freq1 instead of 5.75e6 > > The freq is tuned to 5.75Mhz, so you might be > getting > > 89.8 - 64 + 5.75 = 31.55 ? > > 64 Mhz is the usrp sample freq. 5.75 is the IF freq > the script tunes to. > > --Chuck > > > = mj - m0mik hotstudent.com [are you hot enough?!] __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Re: usrp wfm problem
> Am i missing something obvious? > Fixed it. the "freq1 = blah * 1e6" evaded me. Still not sure on how to receive 433Mhz if anyone knows. thanks. > Also, the max ddc for usrp_fft.py is 32e6 so i'm > assuming the maximum usrp rf frequency is 32Mhz??? > and > the Radio2 wfm reception i'm receiving is some > harmonic. With the standard daughterboard how can i > receive 433MHz for example? > = mj - m0mik hotstudent.com [are you hot enough?!] __ Do you Yahoo!? The all-new My Yahoo! - What will yours do? http://my.yahoo.com ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] usrp wfm problem
> >also... '31.3e6' is Radio2 here in the UK on > 89.8MHz. > >Is there an easy way to convert ddc into the actual > >freq? > > > The freq is tuned to 5.75Mhz, so you might be > getting > > 89.8 - 64 + 5.75 = 31.55 ? > > 64 Mhz is the usrp sample freq. 5.75 is the IF freq > the script tunes to. The file I used to grab the Radio2 signal (89.8Mhz) with was ursp_rx_cfile.py (no 5.75Mhz IF mentioned) with decim=200, dcc-freq=31.3e6. The wfm_rcv_file.py was used to recover the audio from the generated dat file easily. Now, with wfm_rcv.py working and set to the same settings as usrp_rx_cfile.py I cannot recover the audio. I can still see the waveform in usrp_fft.py so it is still there. Am i missing something obvious? Also, the max ddc for usrp_fft.py is 32e6 so i'm assuming the maximum usrp rf frequency is 32Mhz??? and the Radio2 wfm reception i'm receiving is some harmonic. With the standard daughterboard how can i receive 433MHz for example? thanks = mj - m0mik hotstudent.com [are you hot enough?!] __ Do you Yahoo!? Meet the all-new My Yahoo! - Try it today! http://my.yahoo.com ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Re: usrp wfm problem
Quoting mj <[EMAIL PROTECTED]>: > > Am i missing something obvious? > > > > Fixed it. the "freq1 = blah * 1e6" evaded me. > > Still not sure on how to receive 433Mhz if anyone > knows. As RF frequency rises from 0 to 32 MHz, the "digital" frequency goes from 0 to 32 MHz. As RF frequency goes from 32 to 64, digital frequency goes back down to 0. It the repeats from there. So you can receive 433.0 MHz at: 433 - (6*64) = 49 MHz. 433 appears where 49 would 49-32 = 17. 32 - 17 = 15 MHz So tune to 15 MHz to hear 433. This will all be much easier once there are proper RF sections available. Matt ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] problem with audio extraction in NTSC
I deactivated the three fftscopes that I had and now
it works fine. The voice distortion was because the CPU
could not handle the load. It is amazing how much CPU
power the fftscopes consume...
Thanks for the help
Achilleas
Eric Blossom wrote:
On Tue, Feb 15, 2005 at 07:59:45PM -0500, Achilleas Anastasopoulos wrote:
Dear all,
I am working on extracting the audio FM signal from the NTSC
signal, and experimenting with the data file
ntsc-short-complex-baseband-8MS.dat
The idea seems simple: recenter the audio carrier to 0 frequency,
LPF and decimate and then do standard fm demod.
This is done in the attached file.
Unfortunately, although I hear something like
"winter storm will still going to stick around..."
the signal seems highly distorted as if the audio
carrier is very unstable.
I tried to fix this by tracking the video carrier,
but the problem gets worse.
One possible reason for this is that the local oscilator used to
generate the IQ signal is not stable, which unfortunately cannot be fixed...
Can someone verify this problem and/or suggest any solution.
Thanks
Achilleas
This code is known to work with that file...
#!/usr/bin/env python
from gnuradio import gr, eng_notation
from gnuradio import audio
from gnuradio.eng_option import eng_option
from optparse import OptionParser
import sys
import math
#
# return a gr.flow_graph
#
def build_graph (filename, repeat):
fm_demod_gain = 1100.0/32768.0
volume = 1.0
input_rate = 8e6
cfir_decimation = 25
audio_decimation = 10
quad_rate = input_rate / cfir_decimation # 320 kHz
audio_rate = quad_rate / audio_decimation # 32 kHz
fg = gr.flow_graph ()
# file contains complex shorts
# output: short
src = gr.file_source (gr.sizeof_short, filename, repeat)
# deinterleave the shorts and convert them to complex
# input: short; output: complex
deinterleaver = gr.interleaved_short_to_complex ()
# Select only the FM audio channel.
# It's located at +2.75MHz
offset_freq = -2.75e6
channel_coeffs = \
gr.firdes.low_pass (1.0, # gain
input_rate, # sampling rate
200e3,# low pass cutoff freq
200e3,# width of trans. band
gr.firdes.WIN_HAMMING)
# input: complex; output: complex
channel_filter = \
gr.freq_xlating_fir_filter_ccf (cfir_decimation,
channel_coeffs,
offset_freq,
input_rate)
print len (channel_coeffs)
# input: complex; output: float
fm_demod = gr.quadrature_demod_cf (volume * fm_demod_gain)
# compute FIR filter taps for audio filter
width_of_transition_band = audio_rate / 32
audio_coeffs = gr.firdes.low_pass (1.0,# gain
quad_rate, # sampling rate
audio_rate/2 - width_of_transition_band,
width_of_transition_band,
gr.firdes.WIN_HAMMING)
# input: float; output: float
audio_filter = gr.fir_filter_fff (audio_decimation, audio_coeffs)
# sound card as final sink
audio_sink = audio.sink (int (audio_rate))
# now wire it all together
fg.connect (src, deinterleaver)
fg.connect (deinterleaver, channel_filter)
fg.connect (channel_filter, fm_demod)
fg.connect (fm_demod, audio_filter)
fg.connect (audio_filter, audio_sink)
return fg
def main ():
parser = OptionParser (option_class=eng_option)
parser.add_option ("-i", "--input", type="string",
default="ch4.dat", help="read data from FILENAME")
parser.add_option ("-R", "--repeat", action="store_true", default=False)
(options, args) = parser.parse_args ()
fg = build_graph (options.input, options.repeat)
fg.start ()# fork thread(s) and return
raw_input ('Press Enter to quit: ')
fg.stop ()
if __name__ == '__main__':
main ()
___
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Re: [Discuss-gnuradio] Re: usrp wfm problem
It would be useful to have a function that returned the as-aliased frequency for any given input frequency (up to the maximum input frequency of the A/D). Trivial, I suppose, but less opportunity for brain farts that way. Matt Ettus wrote: Quoting mj <[EMAIL PROTECTED]>: Am i missing something obvious? Fixed it. the "freq1 = blah * 1e6" evaded me. Still not sure on how to receive 433Mhz if anyone knows. As RF frequency rises from 0 to 32 MHz, the "digital" frequency goes from 0 to 32 MHz. As RF frequency goes from 32 to 64, digital frequency goes back down to 0. It the repeats from there. So you can receive 433.0 MHz at: 433 - (6*64) = 49 MHz. 433 appears where 49 would 49-32 = 17. 32 - 17 = 15 MHz So tune to 15 MHz to hear 433. This will all be much easier once there are proper RF sections available. Matt ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] problem with audio extraction in NTSC
Quoting Achilleas Anastasopoulos <[EMAIL PROTECTED]>: > > I deactivated the three fftscopes that I had and now > it works fine. The voice distortion was because the CPU > could not handle the load. It is amazing how much CPU > power the fftscopes consume... > Yes, very true. It's not even the FFT part. That is really quick. Its the drawing of the graph. If anybody is interested, I think integrating PGPlot would help this issue a lot. It is supposed to be much faster than wxPyPlot. Matt ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Re: usrp wfm problem
Quoting Marcus Leech <[EMAIL PROTECTED]>: > It would be useful to have a function that returned the as-aliased > frequency for > any given input frequency (up to the maximum input frequency of the A/D). > Trivial, I suppose, but less opportunity for brain farts that way. A good idea. Anyway, to elaborate on what I said before, it is helpful to think in "normalized frequency" terms. The sampling rate is normalized to 1. The nyquist freq is 0.5. Thus, for real samples, the signal is from frequencies of 0 to 0.5. For complex samples, it is from -0.5 to +0.5. In the case we talked about before, 64 MHz => 1. 433 MHz = 6.765625. Drop the whole number part and you are left with 0.765625. Since that is over .5, you reflect it in 0.5. 1 - 0.765625 = .234375 .234375 * 64 MHz = 15 MHz Since we had to do that "reflection", the spectrum is reversed. This isn't a problem for FM, but needs to be taken into account for most modulations. Matt ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Scope and Spectrum Analyzer using WCK
Matt, > Yes, very true. It's not even the FFT part. That is really quick. Its the > drawing of the graph. If anybody is interested, I think integrating PGPlot > would help this issue a lot. It is supposed to be much faster than wxPyPlot. Because I like Tkinter more than wxPython I am playing with the Widget Construction Kit (http://effbot.org/zone/wck.htm). I attach the code for an oscilloscope and spectrum analyzer. I am also working on a network analzyer but it is not usable yet. Using: UP and DOWN keys change y scale SHIFT-UP and -DOWN move y position LEFT and RIGHT keys change time scale TAB switches to next channel SHIFT-TAB to last q for quit. I won't bet it's faster than wxPython. Need to test it. Maybe a block gr.dB would could improve the speed? Thomas wck_oscilloscope.py Description: application/python wck_spectrum.py Description: application/python ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] LED blinking
On Tue, Feb 15, 2005 at 06:18:57PM -0800, Eric Blossom wrote: > > Pull out your trusty ohm meter and with the board unplugged from the > power supply, check continuity across the fuse F501. If you start at > the power connector and follow the trace on the top, it's the first > thing you run into. The ohm meter says that nothing is going through the fuse. Is there a special dance I can do to resurrect this thing? -Rahul -- Rahul Dhar [EMAIL PROTECTED] Actually, my goal is to have a sandwich named after me. pgpPjPOAr6cnq.pgp Description: PGP signature ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Re: usrp wfm problem
> It would be useful to have a function that returned > the as-aliased > frequency for > any given input frequency (up to the maximum input > frequency of the A/D). > Trivial, I suppose, but less opportunity for brain > farts that way. > i tried with python but i'm better with php :) here's a simple rf freq to ddc freq converter, it only works in whole MHz at the mo: http://www.hotstudent.com/gnuradio/ enjoy = mj - m0mik hotstudent.com [are you hot enough?!] __ Do you Yahoo!? Yahoo! Mail - 250MB free storage. Do more. Manage less. http://info.mail.yahoo.com/mail_250 ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] LED blinking
On Wed, Feb 16, 2005 at 03:42:00PM -0500, Rahul Dhar wrote: > On Tue, Feb 15, 2005 at 06:18:57PM -0800, Eric Blossom wrote: > > > > Pull out your trusty ohm meter and with the board unplugged from the > > power supply, check continuity across the fuse F501. If you start at > > the power connector and follow the trace on the top, it's the first > > thing you run into. > > The ohm meter says that nothing is going through the fuse. Is there a > special dance I can do to resurrect this thing? > > -Rahul Fire up your soldering iron, remove the fuse, replace with short piece of wire. [I've had this happen to me too. I suspect that the time constant on the fuse is too small. We may have momentarily high in-rush current that's blowing them.] ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] LED blinking
Quoting Rahul Dhar <[EMAIL PROTECTED]>: > On Tue, Feb 15, 2005 at 06:18:57PM -0800, Eric Blossom wrote: > > > > Pull out your trusty ohm meter and with the board unplugged from the > > power supply, check continuity across the fuse F501. If you start at > > the power connector and follow the trace on the top, it's the first > > thing you run into. > > The ohm meter says that nothing is going through the fuse. Is there a > special dance I can do to resurrect this thing? You must have shorted something. If you are certain you have removed whatever caused the short, desolder the fuse and put a wire in there. Note that inserting or removing daughterboards with power applied is guaranteed to blow the fuse. Also, make sure you use the supplied standoffs so the board don't shift around. Matt ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] fsk mod-demod
I've been working with fsk_tx and fsk_rx between a pair of usrp boards. I've noticed that the fsk_tx has widely different behavior for different settings. On the nominal rx board, I run the fft display, expecting to see the same fft as in the tx window. What I see instead is pretty much noise. When I run the siggen, I've got a nice strong tone at the right frequency. On an external scope, I see the waveform mostly looking ok for the nominal settings (looks a lot like a sine wave, and if you open it up, looks like two sine waves. I've been running with a 4e6 cordic frequency. I'm coming to the conclusion that perhaps something is broken in the usrp interp filter. Any suggestions for settings, or places to look? I'm also trying to cut down the data rate through the USB, and that seems to have some similar problems. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] LED blinking
On Wed, Feb 16, 2005 at 12:57:17PM -0800, Matt Ettus wrote: > Quoting Rahul Dhar <[EMAIL PROTECTED]>: >> >> The ohm meter says that nothing is going through the fuse. Is there a >> special dance I can do to resurrect this thing? > > > You must have shorted something. If you are certain you have removed whatever > caused the short, desolder the fuse and put a wire in there. > > Note that inserting or removing daughterboards with power applied is > guaranteed > to blow the fuse. Also, make sure you use the supplied standoffs so the board > don't shift around. Can I use any wire, or is there a specific gauge, etc., that I need to look for? -- Rahul Dhar [EMAIL PROTECTED] Actually, my goal is to have a sandwich named after me. pgplQvXQaZjaB.pgp Description: PGP signature ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] LED blinking
> Can I use any wire, or is there a specific gauge, etc., that I need to > look for? Any wire that can handle 3 amps. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] LED blinking
Is it just me, or does anybody else think it would be a fine idea to drop an in-line fuse into the power line along with bypassing the soldered down fuse? Just in case there's actually a short somewhere in the board that we really don't want to expose catastrophically. On Wed, 2005-02-16 at 16:06 -0800, Matt Ettus wrote: > > > > Can I use any wire, or is there a specific gauge, etc., that I need to > > look for? > > > Any wire that can handle 3 amps. > > > ___ > Discuss-gnuradio mailing list > Discuss-gnuradio@gnu.org > http://lists.gnu.org/mailman/listinfo/discuss-gnuradio > > -- Pat Crean (269) 925-5329 --- Quidquid latine dictum sit, altum viditur ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] problem with audio extraction in NTSC
Matt, Yes, very true. It's not even the FFT part. That is really quick. Its the drawing of the graph. If anybody is interested, I think integrating PGPlot would help this issue a lot. It is supposed to be much faster than wxPyPlot. I just downloaded and installed PGPlot. The native interface appears to be C and Fortran but I found a project called ppgplot that has a python interface. Is this what you had in mind? I'll try to get something working with these two. -David Carr ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] problem with audio extraction in NTSC
On Wed, Feb 16, 2005 at 09:11:36PM -0600, David Carr wrote: > Matt, > > >Yes, very true. It's not even the FFT part. That is really quick. Its > >the > >drawing of the graph. If anybody is interested, I think integrating > >PGPlot > >would help this issue a lot. It is supposed to be much faster than > >wxPyPlot. > > > > > I just downloaded and installed PGPlot. The native interface appears to > be C and Fortran but I found a project called ppgplot > that has a python interface. Is this what you had in mind? I'll try to > get something working with these two. > > -David Carr Great. I don't know anything about this package. It would however be great it it worked with wxPython. I'd hate to give up the cross platform portability. Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
