Thanks Pavel! Please keep us posted on the data decoded when you have time.

On Wednesday, December 4, 2013, Pavel Milanes Costa wrote:

Hi to all...

Just now I have heard the CAPE-2 sat in Orbit 221 over Camagüey Cuba (FL11bj) a very good pass (89 degrees) 4 dec 2013 ~1315z

Clean packet 1200 bps signal... I'm runing to get to work and had no time to setup the decoder...

Hard here is RTL-SDR + LNA + Gqrx + Gpredict for doppler

73 _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb

Hi Phil and others.

The last snapshoot of gqrx in the Csete ubuntu ppa is full of new features, among them is the ability to behave as a generic hamlib server...

Visit http://www.gqrx.dk (no affiliation, just a user...)

Configuring gqrx to accept connections is two click away and setting a new radio interface in Gpredict with the localhost and correct port setting makes the connection smooth..

Alex has provided an explanation about the doppler control moving the cursor in the spectrum rather than the center freq that makes the doppler tracking so easy...

The cursor keeps moving down with doppler even if you click/move it between the TLM/transpoder taking AO-73 as an example... good...

And you can push corrections at full speed, today I tested 100ms updates and works ok with funcube TLM...

About the audio... I have a kind of success today with the config decoding local 9600 bps in a local packet channel... not tested on sats yet..

The new gqrx has a "network audio broadcast" at one click away.

The I connect to the audio stream with nc and pipe the audio with sox to the second audio card that has soundmodem with 1k2, 4k8 and 9k6 modems on demand...

Alex mentions that the DireWolf team plan to make a "network sink" as a new feature in new versions... that will ease the things a lot...

listen or axlisten (depends of your source of ax25-libs/tools packages) serve as KISS raw packet visual aid and save them to a file also for later.

I said kind of success because sox sucks my CPU/RAM and appears to be a fight between sox and soundmodem some times... I have to tweak this a little...

Alex Csete is doing a good job with SDR and linux, it's the only (nice GUI, native, easy and ham oriented, not just gnuradio) software for managing the RTL-SDR in linux, if I'm wrong please correct me. (I like having options!!!)

The only feature I miss is the save baseband as IQ in a file... for the moment only the audio...

I hope my english let your make an idea of my setup here...

73 de CO7WT, from Cuba.

El 04/12/13 19:33, Phil escribió:

On 12/04/2013 11:24 PM, Pavel Milanes Costa wrote:

...

Hi to all...

...

Hard here is RTL-SDR + LNA + Gqrx + Gpredict for doppler

Hello Pavel,

Just wondering, how you interface Gpredict with Gqrx to control the tuning? Also, how are you interfacing Gqrx with your packet decoding software?

Yes, the last snapshoot is dated around the end of november...

Last night I realize that I can tap the audio out from the main sound card on the desktop and route it to the mic-in input of the second sound card (limited of course) and select the input from software, that must eliminate the hungry sox and sox/sounmodem troubles.. some times the low tech/hardware solutions is the best...

The second sound card is dedicated to digimodes in HF and VHF 9k6 bps packet that carry my email traffic in/out the net... using TCP/IP...

73

El 05/12/13 02:07, Phil escribió:

On 12/05/2013 03:25 PM, Pavel Milanes Costa wrote:

...

Hi Phil and others.

The last snapshoot of gqrx in the Csete ubuntu ppa is full of new features, among them is the ability to behave as a generic hamlib server...

Thank you Pavel for your detailed description. It sounds like Gqrx has advanced a lot since I compiled my current version 18 months ago.