[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

Re: KO-23, AO-10

>From: Stacey E. Mills, M.D. <w4sm@cstone.net>
>To: Amsat Bulletin Board <amsat-bb@AMSAT.Org>
>Date: Monday, September 14, 1998 10:39 AM
>Subject: [amsat-bb] KO-23, AO-10

>On a pass over my QTH today, I was unable to hear AO-10's beacon, even at a
>comparatively close range of about 10,000 km.  Has anyone heard the beacon
>in the last few days??

I've been listening for the past week but haven't heard much over Guam.
Tonight I really sat here and listened and thought I heard the beacon come
out of the noise for 3 or 4 seconds every couple of minutes.  Range was
7000 KM but I wasn't even sure if it was the beacon I was hearing because
it came and went so quickly.

I ran the audio into my computer and used AF9Y's FFTDSP program to
take a look at the signal and was able to see the beacon powering up 
every 28 seconds  for 4 or 5 seconds.  Every third time it came up
it was relatively strong (and just audible) compared to the two other
weaker power ups that were way down in the noise that only the fourier
analysis could resolve.  I measured an 83 second cycle altogether.

I'd have to say the beacon was powering on and off rather than an 
antenna fade effect because I could see the tone rising and dropping
rather quickly each time it came on.  I'm just not sure why there was
a stronger signal out of every three.  I can't even begin to imagine 
how the bird is rotating.  Assuming that all the PV cells are the same
I'd have to say the antenna was pointing away or shaded from me
two of three times. 

-Mike McCarty
 Yigo, Guam


Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org