[App_rpt] New USB Fob attempt...

[David Powell-Williams]

Steve:

Gee, I'm beginning to think if your name isn't Steve or Jim, you're just a
nobody in the app_rpt/AllStar world :))

This is to let you know that you are not alone with the audio issue.

Jim WB6NIL and I have been working to add the Kenwood TM-271 to the list of
equipment that is supported for remote base use.

To this end, I put Debian Etch on a Dell Inspiron (2.6 GHz P4, 700 MB
memory, kernel 2.6.24).  After much work by Jim, we got the RB interface
working correctly.  However, the audio from Asterisk to iaxrpt was very
garbled. Many attempts to correct it failed.

Next step was to put the same distro but with a 2.6.22 kernel on a second
computer (dual core AMD, 1 G memory).  This time the audio to iaxrpt was
just like your description...totally unintelligible blurps and pops. Jim
traced this down to issues with ztdummy and was able to correct it.

The final step (to date) was re-installing Debian on the Inspiron with a
2.6.18 kernel. I used zaptel-1.4.current.tar.gz from the Digium repository
to generate ztdummy.  This cured the audio distortion from Asterisk to
iaxrpt but introduced garbled audio when going from iaxrpt to Asterisk.

This is where we are today. I should be clear that this is not an iaxrpt
issue.  Radio tune txvoice produces a very distorted sine wave as seen off
the air by a service monitor.  A 'scope placed directly on the USB FOB audio
output also shows a poor waveform with 'radio tune'.

Jim has been nothing short of fabulous in working on this problem.  If we,
meaning 99.9% Jim, get a solution that produces good audio in both
directions, I'll be sure to post a note here.

I hope this helps.

73,

David
VE7MQ.