Usrp_wxapt_rcv.py


#1

Hi All,

My name is Patrik T. from Vasa, Finland.

I this week received the Ettus USRP with daughterboards BasicRX and
800-2400 MHz RX from CA, US.
I fired it up today to test the BasicRX side using the usrp_wfm_*.py and
nbfm and everything works as expected. I am able to hear what ever FM
channels with great quality.

Since I am a wxapt guy, http://www.poes-weather.com/, the
usrp_wxapt_rcv.py was my next test in the examples directory.

NOAA 17 @ 137.62 MHz was here just (usrp_wxapt_rcv.py -f 137.62e6 -V 0)
and all I could hear was German radio comming through. Extremly faintly,
I could hear the TICK-TOCK sound in the background (I also could have
been imagining, it was so unclear) and (just) some change in the graph
while the satellite was over me (45 degrees).

When I changed to the R2FX-receiver (dedicated APT-receiver) the signal
is there http://www.df2fq.de/english_version/r2fx_eng.html

I could not find an author to the usrp_wxapt_rcv.py nor could I find a
GRC block diagram for it.
I can see that the author is aiming for 32 kHz bandwith but I suspect
there is something missing?
APT spec is at http://www2.ncdc.noaa.gov/docs/klm/html/c4/sec4-2.htm

I’m using Fedora 9 and GnuRadio 3.1.3 (latest stable release, not from
svn)

Any help appreciated,
Thanks,
Patrik