Autonotch Loop about leansdr HOT 8 CLOSED

Your signal looks clean, the spectrum has a reasonably flat top; that's why the ANF wanders around, and this should be harmless. Have you tried "--anf 0" ?

ANF will probably be disabled by default in a future release.

from leansdr.

SS is signal strength; I have no idea why it is wobbling like that.
MER is Modulation Error Ratio, a kind of SNR for constellation-based modulations.
Yellow is an estimation of the percentage of recovered packets.

Your flowgraph seems to be a modulator for DVB-S2. Unfortunately leandvb cannot decode S2 yet. Hopefully I will implement it before Es'hail2 launches.

from leansdr.

Yes, recovery is incorrectly reported above 100% for some combinations of settings.

In your video there are sequences where leandvb fails to lock despite a very good MER (tight constellation clouds). This should not happen. You may want to:

• Check whether the CPU is overloaded (note: leandvb is single-threaded)
• Try the "--fastlock" option (increases CPU usage)
• Record IQ samples to a file, then demodulate afterward
• Or pipe directly from rtl_sdr to leandvb (when writing to a file, rtl_sdr may silently lose samples if the OS pauses while flushing its cache).

There are other sequences with poor MER (wide constellation clouds). To demodulate that you need the "--viterbi" option (CPU-intensive).

Regarding mplayer, I find that it is best to specify as many parameters as possible rather than rely on auto-detection, as in:
mplayer -demuxer mpegts -tsprobe 1 -vid 256 -aid 257 -vc ffmpeg2 -ao null -
To check whether the TS is good, record it to a file and run mplayer afterward.
Maybe the decoder that F5OEO selected for rpidatv (omxplayer ?) is a better choice for live streams.

from leansdr.

Thanks for the fast response! It's super flat as I'm going straight in via a short sma cable (just for test).

I've tried with "--anf 0" and the wandering goes away but no video yet.

I've put up my flow graph too. I'm sure some others would find it useful. The .ts file is the one you recommend too.

In the gui - I couldn't explicitly find out what the lines each meant. Blue is obvious, but SS and MER? And the yellow? Interesting criss-crossing of the red... unsure what that means.

Chris

from leansdr.

Ah! That'd be it then! I'll try DVBS then and see how we go. Will report back in a little bit. Chris

from leansdr.

Almost there, modded gr-dvbs tx grc file to Tx properly. See attached. Almost there - will try some mplayer settings next. Suggestions would be great still though!

MER now 110%! (or perhaps that's bad?)

Chris

from leansdr.

Here's where it's at, comments welcome on the last hurdles. Will close tomorrow. Best, Chris

https://www.youtube.com/watch?v=JPkJTpsf5CM

from leansdr.

Understood - many thanks pabr! 73 C

from leansdr.