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Bad audio from analog_bridge


JF
 

Hi all,
I trying to broadcast our club bm tg to broadcastify.  I installed mmdvm_bridge, analog_bridge and md380-emu as I don’t have ambe dongle.  I’m monitoring the audio output with nc -l -u -p 32001 | play -t s16 -r 8k -c 1 - 
 
I heard the voice correctly but there is a background noise kinda a pulse, I tried playing with gain but no luck, is someone can help with this?
 
JF


Mike Zingman - N4IRR
 

You are listening to USRP audio packets.  USRP is a simple wrapper around the audio, but it is causing your sound issues.  Look at USRPAudio.py for a python solution to audio monitoring.


Mike KB8JNM
 

Just a guess...

but I would look at the analog side in the area of other radios didital noise getting back through. Perhaps from a synthesized tx/rx where you are using a analog sound dongle.

On 12/3/2019 1:03 PM, JF via Groups.Io wrote:
Hi all,
I trying to broadcast our club bm tg to broadcastify.  I installed mmdvm_bridge, analog_bridge and md380-emu as I don’t have ambe dongle.  I’m monitoring the audio output with nc -l -u -p 32001 | play -t s16 -r 8k -c 1 - 
 
I heard the voice correctly but there is a background noise kinda a pulse, I tried playing with gain but no luck, is someone can help with this?
 
JF


JF
 

Works perfect with usrpaudio.py thanks!


Steve N4IRS
 

Glad to hear it. That's what usrpaudio.py is for.
You might want to post your command line so others can learn from it.

73, Steve N4IRS

On 12/4/2019 2:31 PM, JF via Groups.Io wrote:
Works perfect with usrpaudio.py thanks!


JF
 

Hi Steve, I’m not sure what command line you are talking about.
 
My setup is:
BM<>mmdvm_bridge<>analog_bridge<>usrpaudio.py
 
Here is the command, I run those manually to monitor them.

./MMDVM_Bridge
./Analog_Bridge
./md380-emu
./USRPaudio.py
 
Usrpaudio.py throws a couple of error at launch but it works
 
Actually I run this on a debian virtual machine on my laptop, at the end I plan to run this on aws where there is no sound card so I think I’ll have a another funny troubleshooting weed-end :)


Steve N4IRS
 

OK,
I thought you were planning to send the audio to Broadcastify.

Steve

On 12/4/19 10:08 PM, JF via Groups.Io wrote:
Hi Steve, I’m not sure what command line you are talking about.
 
My setup is:
BM<>mmdvm_bridge<>analog_bridge<>usrpaudio.py
 
Here is the command, I run those manually to monitor them.

./MMDVM_Bridge
./Analog_Bridge
./md380-emu
./USRPaudio.py
 
Usrpaudio.py throws a couple of error at launch but it works
 
Actually I run this on a debian virtual machine on my laptop, at the end I plan to run this on aws where there is no sound card so I think I’ll have a another funny troubleshooting weed-end :)


JF
 

Ok I see. I did’t work on that part yet but I plan to use darkice as broadcast feed.
 
I think I’ll need to install a virtual sound card and then pipe the audio into darkice.


Patrick Perdue
 

If you can get raw PCM to stdout, you can pipe that audio to lame, then pipe lame to ezstream. No sound card, virtual or otherwise, required. You could perhaps do this with ffmpeg as well. Going the Darkice and loopback device will work if needed, too. This is how I have streamed output from op25 on a Raspberry Pi.


Philippe, f5rvx
 

and how to run usrpaudio.py from systemd ?

I created the service "usrpaudio.service" in which I noted:
ExecStart = /opt/Analog_Bridge/./USRPAudio.py -s> / dev / null 2> & 1
User = root

And I get the following errors:
Dec 2 23:47:43 localhost USRPAudio.py [598]: File "/opt/Analog_Bridge/./USRPAudio.py", line 164, in <module>
Dec 2 23:47:43 localhost USRPAudio.py [598]: ch = getch ()
Dec 2 23:47:43 localhost USRPAudio.py [598]: File "/opt/Analog_Bridge/./USRPAudio.py", line 145, in _getch
Dec 2 23:47:43 localhost USRPAudio.py [598]: old_settings = termios.tcgetattr (fd)
Dec 2 23:47:43 localhost USRPAudio.py [598]: termios.error: (25, 'Inappropriate ioctl for device')


Thank you so much.
Philippe

Le 04/12/2019 à 20:33, Steve N4IRS a écrit :

Glad to hear it. That's what usrpaudio.py is for.
You might want to post your command line so others can learn from it.

73, Steve N4IRS

On 12/4/2019 2:31 PM, JF via Groups.Io wrote:
Works perfect with usrpaudio.py thanks!