Re: [Discuss-gnuradio] Re: DReaM and gnuradio

[Eric A. Cottrell]

Matteo Campanella wrote:
> Search the list on the subject - I did a posting some time ago about
> using DRM decoder with USRP bymeans of tmpfs ram based named pipe for
> interface...

Hello,

I looked it up and tried it with the analog demodulator.  The local AM
station came out with half speed audio!  I suspect the problem is I am
outputing two shorts to represent a complex waveform.  It appears
DReaM's -C parameter does not work with files and it expects just audio
samples.  Maybe I will "fix" it.  So I am still using my USB audio
approach but your approach seems better in the long run.  Not being a
real Unix geek and serving time in Windows Prison means I do not think
of neat things like fifos.

I did some rough measurements and using the USRP with the AOR 5000 IF
Out gains me 8 to 10 db SNR over the "No-Mod" method.  It appears I have
to get a 10 db or so amplifier for the IF Output.  I have to run with
AGC Off to get a somewhat decent output.  I really like GNUradio and the
USRP so far.  I needed a 10.7 MHz to 12 KHz converter and I built one in
software with some help.

73 Eric

73 Eric