With the time component factored with the packet, I would suspect APRS. Quite possibly the radio that was the APRS' Transmitter has your pair as channel 1 in the memory and some how got the DTSS portion switched on as well. This would account for the DTMF burst as the APRS controller is not waiting for the DTMF to be sent before the burst. If you can filter the tones to the point where the packet will decode you should get Lat, Long and a callsign.
On 12/12/06, Roger Grady <[EMAIL PROTECTED]> wrote: > At 04:41 PM 12/12/2006, Roger Grady wrote: > > >Sounds like very weak packet bursts to me. > > I looked at the sample with a waveform editor (Audacity) - there's > definitely data riding on the 100Hz tone, at around 5-10% of the 100Hz > deviation. It looks like it continues during the DTMF bursts also but it's > hard to tell for sure visually. > > The data looks like two-tone, low tone is probably 1300, high tone between > 2000-2100. The higher frequency is harder to measure because there aren't > as many cycles of it in a row as the lower. The data appears to start with > a pilot of 7 cycles of low tone, followed by 2 cycles of high tone, the > pilot lasts for just under 180ms. > > After the 3rd DTMF burst, there's another 50ms burst of something more > complex. It may be a continuation of or another DTMF burst, coupled with > the two-tone data but the overall level of the signal is higher, and the > two-tone is much much higher than before. > > All in all, an interesting signal. I hope somebody recognizes it as it's > got my curiousity aroused. > > Roger Grady K9OPO > > > > > > > Yahoo! Groups Links > > > >
