From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jonathan Lassoff Subject: Re: Soundmodem Not Decoding Real Packets Date: Fri, 1 Jul 2005 10:34:12 -0700 Message-ID: <40764501050701103468d58aec@mail.gmail.com> References: <46479.194.154.200.89.1120206709.squirrel@mail.lx2gt.lu> Reply-To: Jonathan Lassoff Mime-Version: 1.0 Content-Transfer-Encoding: 7BIT Return-path: In-Reply-To: <46479.194.154.200.89.1120206709.squirrel@mail.lx2gt.lu> Content-Disposition: inline Sender: linux-hams-owner@vger.kernel.org List-Id: Content-Type: text/plain; charset="us-ascii" To: Luc Langehegermann , linux-hams@vger.kernel.org On 7/1/05, Luc Langehegermann wrote: > Hello Jonathan, > > > I've been trying to get Tom Sailer's soundmodem to decode AX.25 packets. > > I've > > been able to see the audio coming in from the radio and from other > > machines > > transmitting packets through a cable. The only problem is that the DCD can > > be > > too sensitive and turn on when there is nothing but just inducted noise in > > the > > cable from somewhere. The noise in normal, and the level is very, very > > low. But, > > the problem is that soundmodem tries its best to try and decode the noise. > > But > > when a real packet comes down the line, it tries but fails to decode it > > properly. I think that I have an issue with audio levels, but I'm open to > > being > > wrong. Does anyone on list have any good ideas of things to try? > > > > I had a similar issue in the past, which can occur if you use the ALSA > soundcard drivers. If you use ALSA for your hardware, are you sure to also > use the new soundmodem, which supports it directly? The problem could be, > that your sound driver does sample rate conversion, which can be the > reason for not decoding packets. > > Luc > I tried the decoding with both ALSA and direct OSS, but it still doesn't seem to work properly either way. I'm using soundmodem-0.9 Jonathan (KG6THI)