[Hackrf-dev] Static/warbling non reception issue

[David Goldstein]

Maybe someone has an extio that will fix this...?
On Apr 30, 2016 11:39, "Dominic Spill" <dominicgs at gmail.com> wrote:

> I can't remember how it works in SDR#, but in GQRX you can just click
> on the display and it will start demodulating that frequency instead
> of the centre frequency.  It's probably the same in SDR#
>
> Dominic
>
> On 30 April 2016 at 16:36, davidmarkusgoldstein at gmail.com
> <davidmarkusgoldstein at gmail.com> wrote:
> > Hi Dominic,
> >
> > Yeah 101.5 and 103.3 are right in town or nearby.  I will have to test
> the
> > offset features better...I will let you know how this goes.
> >
> > David
> >
> >
> > Sent via the Samsung Galaxy Note® II, an AT&T 4G LTE smartphone
> >
> >
> > -------- Original message --------
> > From: Dominic Spill
> > Date:04/30/2016 11:23 AM (GMT-05:00)
> > To: david.goldstein.93 at alumni.vanderbilt.edu
> > Cc: hackrf-dev
> > Subject: Re: [Hackrf-dev] Static/warbling non reception issue
> >
> > On 30 April 2016 at 00:32, David Goldstein
> > <davidmarkusgoldstein at gmail.com> wrote:
> >> Hi, here's a screenshot of the settings that I can change, plus the
> >> spectrum analysis shot.  The audio I get is heavily distorted on the
> strong
> >> local FM stations.
> >
> > The station at 101.5MHz looks like an excellent signal.
> >
> >> So, I have no idea what's wrong, except that it could be the sound
> driver
> >> or on-board sound.
> >
> > Are you demodulating the signal at the centre frequency?  Or at an
> > offset?  The spike in the middle is the DC offset, so if you're
> > demodulating there you're going to see bad data.  It's explained in
> > more detail here:
> >
> https://github.com/mossmann/hackrf/wiki/FAQ#what-is-this-big-spike-in-the-center-of-my-received-spectrum
> >
> > Thanks,
> >   Dominic
> >
> >> -----Original Message-----
> >> From: Dominic Spill [mailto:dominicgs at gmail.com]
> >> Sent: Friday, April 29, 2016 5:40 PM
> >> To: davidmarkusgoldstein at gmail.com
> >> Cc: hackrf-dev
> >> Subject: Re: [Hackrf-dev] Static/warbling non reception issue
> >>
> >> On 29 April 2016 at 17:31, davidmarkusgoldstein at gmail.com
> >> <davidmarkusgoldstein at gmail.com> wrote:
> >>> Hi, how can I test the hackrf to see if it's damaged?  I have sound
> >>> card issues, it seems, on my i7-2600 win7 64 bit system, so I tried it
> >>> on a Vista laptop and experienced the same: static and choppiness and
> >>> some distorted voice on local fm.  So perhaps the radio is damaged.
> >>
> >> This doesn't necessarily mean that the radio is damaged, although we can
> >> help to test whether it is, but it may be something not quite right in
> your
> >> settings.  Telling us which settings you are using for sample rate,
> gain,
> >> filter, etc would really help us to diagnose the problem.
> >>
> >> Thanks,
> >>   Dominic
> >>
> >>> -------- Original message --------
> >>> From: Dominic Spill
> >>> Date:04/28/2016 7:31 PM (GMT-05:00)
> >>> To: davidmarkusgoldstein at gmail.com
> >>> Cc: hackrf-dev
> >>> Subject: Re: [Hackrf-dev] Static/warbling non reception issue
> >>>
> >>> On 28 April 2016 at 20:28, davidmarkusgoldstein at gmail.com
> >>> <davidmarkusgoldstein at gmail.com> wrote:
> >>>>
> >>>> Hi, this might not be a tech support list but I don't know what to do
> >>>
> >>> Hi David,
> >>>
> >>> We're happy to provide tech support through this mailing list; I'm
> >>> sure we'll be able to help you.
> >>>
> >>>> ...everything seems set up properly but I get static and broken up
> >>>> voice broadcast on local fm.  I think it's the alc889 Realtek sound
> >>>> card doing this...I had this issue with a winradio g 315 because I'm
> >>>> running win 7 64bit.
> >>>
> >>> Are you using SDR# on your Win7 install?  Could you give us some
> >>> examples of the settings you are using?  If it's easier, you can
> >>> attach a screenshot of the setting panel in SDR# (or whichever tool
> >>> you're using).  You could also attach a screenshot of the tool so that
> >>> we can see how strong the signal is compared to the background noise.
> >>>
> >>>>  They tweaked a driver for me and I got the winradio running but I
> >>>> don't know what to do now with the hackrf I have, if it is the sound
> >>>> card at all.  Any tips?
> >>>
> >>> One option would be to try not using realtime processing.  Capture ~20
> >>> seconds FM station to a file, then demodulate it from the file
> >>> afterwards.  Finally, you should be able to play back the file as
> >>> audio.  If it's a problem with the quality of the signal being
> >>> received, the output will still be choppy, but if the output is smooth
> >>> we can look at where else things may be going wrong.
> >>>
> >>> It certainly looks like you have enough CPU power and RAM to support
> >>> the task that you're trying to do, so we'll have to narrow down where
> >>> the problem could be.
> >>>
> >>> Thanks,
> >>>   Dominic
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://pairlist9.pair.net/pipermail/hackrf-dev/attachments/20160501/d48f2a32/attachment.html>