casebeer / afsk Goto Github PK

Opening this to track the issue, with more details to come, but:

On my specific setup, whenever I try to pass audio directly to the sound card, the output is choppy (i.e. incremental delays in audio playback).

Outputting to a wav file, and playing back (using aplay) through the same sound card is OK.

I've found that replacing the following line in afsk.py:encode() eliminates the problem:

		#multiply(modulate(framed_data), constant(0.5)),
		modulate(framed_data),

To Reproduce:

$ ALSA_CARD=Device aprs -c W2GMD "Test"

Versions:

Python 2.7.9

afsk==0.0.3
audiogen==0.1.2
bitarray==0.8.1
PyAudio==0.2.10

portaudio19-dev 19+svn20140130-1
libportaudio2:armhf 19+svn20140130-1

Linux latrans 4.4.38-v7+ #938 SMP Thu Dec 15 15:22:21 GMT 2016 armv7l GNU/Linux

Distributor ID: Raspbian
Description: Raspbian GNU/Linux 8.0 (jessie)
Release: 8.0
Codename: jessie

Audio Output:

card 1: Device [C-Media USB Audio Device], device 0: USB Audio [USB Audio]
Subdevices: 1/1
Subdevice #0: subdevice #0

I believe it is presently hard coded to WIDE2-1. For use with mobile stations it is recommended to have WIDE1-1,WIDE2 as described here... http://wa8lmf.net/DigiPaths/NNNN-Digi-Demo.htm.

The reason I mention this is that this code has now found itself being used inside a raspberry pi zero for a low cost mobile APRS tracker as described here.. http://midnightcheese.com/2015/12/super-simple-aprs-position-beacon/

Perhaps default to WIDE2-1 as present but a -m command line to specify mobile use?

The AFSK library doesn't load properly when I run it on my Fedora 30 system with Python 3.7.

Some of the issues that occur:

>>> import afsk
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python3.7/site-packages/afsk/__init__.py", line 2, in <module>
    from afsk import encode
ImportError: cannot import name 'encode' from 'afsk' (/usr/local/lib/python3.7/site-packages/afsk/__init__.py)

I experienced further errors in the 'audiogen' library, but it appears these have already been reported in casebeer/audiogen#2.

Hi There, I can build this fine on my Linux/Mac units. But I cannot do the same for Windows. I'm using Windows 8 (I know, not my fault), installed Python 2.7 and the VCforPython27.exe.

Pip.exe install works fine and the binary compiles and runs, but I want to edit the code and have a dig around. Any suggestions?

The typical method of 'python setup.py install' works fine, and gives a good output like my Linux/Mac machines. But it then reports: 'failed to create process'.

Thanks in advance for the help, C

Hi,
this is a great piece of work! Unfortunately it does not accept APRS-SSIDs with more than one digit for the suffice (like -11 for a balloon).

The fix is simple AFAIK:

Change line 114 in ax25.py to

 assert(len(ssid) <= 2)