Hi, KD9GN
I'm tried your example
$ rtl_fm -f 100.0e6 -N -s 170e3 -o 4 -A -r 32e3 -l 0 - | play -t raw -r 32k -e signed-integer -b 16 -c 1 -V1 -
-: (raw)
Encoding: Signed PCM Channels: 1 @ 16-bit Samplerate: 32000Hz Replaygain: off Duration: unknown
In:0.00% 00:00:00.00 [00:00:00.00] Out:0 [ | ] Clip:0 Found 1 device(s): 0: Realtek, RTL2838UHIDIR, SN: 00000013
Using device 0: ezcap USB 2.0 DVB-T/DAB/FM dongle Found Rafael Micro R820T tuner Oversampling input by: 2x. Oversampling output by: 4x. Buffer size: 6.02ms Tuned to 100340000 Hz. Sampling at 1360000 Hz. Output at 32000 Hz. Exact sample rate is: 1360000.050439 Hz Tuner gain set to automatic. In:0.00% 00:00:01.02 [00:00:00.00] Out:49.1k [!=====|=====!] Hd:0.0 Clip:39
But I listen only QRM, there are not music)
What I'm do wrong?
Kyle, thank you for explanation -E option
73! UT4UAZ
On Thu, Nov 15, 2012 at 8:01 AM, KD9GN kd9gn@lolling.org wrote:
On 11/15/2012 05:13 AM, Adam Nielsen wrote:
Correct on the offset. -E is something else entirely though.
Very interesting! Thanks for the explanation.
I had been wondering whether it was related to the new librtlsdr code which appears to use a non-zero IF with the E4000 to avoid the centre spike, so it's good to know what it's really for.
Cheers, Adam.
I am not sure if this helps anyone at all but I was playing around with the command line options available with rtl_fm while trying to listen to my favorite local FM Broadcast radio station and had pretty good audio results with this ....
rtl_fm -f 88.9e6 -N -s 170e3 -o 4 -A -r 32e3 -l 0 - | play -t raw -r 32k -e signed-integer -b 16 -c 1 -V1 -
as you probably already know, when you run rtl_fm without any options you get a list of all of the command line switches as well as some example commands.
I couldn't tell much difference between using the -A option or not using it.
By the way, I am using an eZcap 668 (E4000/rtl2832u)
Hope this helps. 73 - Dave KD9GN