It seems that we have been down this road before......
The short data burst is not paging. The 'squawk' that seems to be at the end of the 'offenders' individual transmissions in the first part of the clip is recognizable to me. It is 1200 baud, and from the sound/duration it is Motorola MDC1200 coding. The MDC1200 is used for ID and status on public safety and other systems. Several hams in my area have taken to using the Motorola radios with the MDC1200 system to ID and contact each other (selective calling, status, emergency, etc.). It is not likely that it would give us much info to go on, if we could decode it. The MDC 1200 system uses hex number data, it is not ASCII. The data, when decoded on another radio will be a 4 digit number. There is a short write up (and sound samples) on: http://en.wikipedia.org/wiki/MDC-1200
Another possibility is that someone has established a simplex Echolink system on the uplink. That may be why some have reported a CW id, and the carrier hanging on for longer than a normal simplex transmission.
Perhaps someone with AMSAT could contact the ARRL Official Observer coordinator. They have been known to send out requests for the OO corps to listen for specific interference problems. This might be important enough to get all ears listening. I don't hear it here.
73 Ernie W8EH
Bruce Robertson wrote:
Once I started hearing this QRM while listening to AO-27, I recorded the tail-end of the 20:00Z pass. Interested persons may download a mp3 file at http://heml.mta.ca/Amsat/ (There is no promise that this link will be in place for a long time.)
Besides the beeps and long periods of carrier-induced silence, there are some conversational snippets which seem to me from native English speakers. One of the amateurs on the bird suggested the QRM comes from a pager, and I labeled the file as such, but I don't mean to suggest that this identification is secure.