Thanks for plugging my son's program, Greg! I've been amazed at how accurate it is.... mode changes typically occur within seconds of predicted times, and, as the AO-27 site notes, the onboard clock can be up to 10 seconds off.
73,
George, KA3HSW
----- Original Message ----- From: "Greg D." ko6th_greg@hotmail.com To: kq6ea@pacbell.net; amsat-bb@amsat.org Sent: Sunday, June 28, 2009 1:02 PM Subject: [amsat-bb] Re: AO-27 Question
Hi Jim,
Interesting... That was probably the pass I was trying to work AO-27 too, but I didn't have any success at all. All I got back was hash, with others audible below it. I think my uplink was interfering my downlink locally, though it went away after the pass. Gotta work on that.
But, in answer to your question, the satellite has a scheduled sequence that it goes through. There's a program to predict when the different phases are going to kick in, downloadable from http://sites.google.com/site/ao27satellitescheduler/ and it shows exactly what you and I experienced during the pass. I suspect it appeared like the satellite turned on with conversations already in progress because they jumped the gun a bit on the uplink, or weren't aware of the timer and were transmitting without being able to hear anything. The digital parts of the pass are telemetry, and you can decode and contribute what you hear to the archive. The main page is http://www.ao27.org.
Enjoy,
Greg KO6TH