rtl_fm problem with capture audio

This is merely a historical archive of years 2008-2021, before the migration to mailman3.

A maintained and still updated list archive can be found at https://lists.osmocom.org/hyperkitty/list/osmocom-sdr@lists.osmocom.org/.

Vitaliy Kulchevych coolchevy at gmail.com
Wed Nov 14 23:37:16 UTC 2012


Thanks, realy -l 0 help me. Problem with correct frequency.
Why it is not correct?
When I set -f434500000 -> Tuned to 434753575 Hz
                 -f100000000 -> Tuned to 100253575 Hz

Can you explain this?
How I can calculate right frequency?

On Wed, Nov 14, 2012 at 11:39 PM, Adam Nielsen <a.nielsen at shikadi.net> wrote:
>> I use rtl_fm, check any options, but I can't listen any good sound :(
>>
>> For example: rtl_fm -f 10000000 -s 44100  - | mplayer - -quiet
>> -rawaudio rate=8000:bitrate=44100 -demuxer rawaudio
>
>
> -s means you are setting the RF bandwidth to 44.1kHz.  Maybe you meant -r to
> set the output sampling rate to 44.1k?
>
> Either way your -rawaudio option is setting the input sampling rate to 8kHz,
> so the audio is going to sound like it has been slowed down.
>
> You may want to add the "-l 0" option to rtl_fm to disable squelch while
> you're testing, just to see whether you are getting any audio at all.  If
> the signal isn't that strong the default squelch value will cause you to
> only hear silence.
>
> Cheers,
> Adam.
>



-- 
live free or die;




More information about the osmocom-sdr mailing list