Thanks, Bret, now for those of you who have TS2,000's, I tried to tune to
the frequency in Bret's message, however my ts2K is not set to be able to
tune to anything other than a five or zero on the 440 megahertz band. Also,
I was not able to put the receiver in SSB mode, so how, too, guys?
Thanks.
Fred Olver n9bso
----- Original Message -----
From: "Brett Winches" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, January 23, 2008 2:20 PM
Subject: AO16 NEWS
> AO-16 Satellite Serves as Voice Repeater
>
> Launched in January 1990, AMSAT-OSCAR 16 (AO-16) -- a digital satellite
> -- has been unavailable for use while the command team dealt with a
> serious computer problem. The satellite has since been recovered, and
> is now a voice repeater, at least for an unspecified "test period" using
> FM voice on the uplink, but SSB voice on the downlink.
>
> Since AO-16 was recovered approximately six months ago, the command team
> -- Bruce Rahn, WB9ANQ, Jim White, WD0E, and Mark Hammond, N8MH
> -- attempted to reload the satellite software almost a dozen times
> without success. The team performed a series of memory tests that
> pointed toward a hardware failure that prevented the spacecraft software
> from restarting successfully.
>
> AMSAT Vice President of Operations Drew Glasbrenner, KO4MA, said, "After
> concluding that the spacecraft computer system was damaged, and as
> discussions about decommissioning were taking place, Jim recalled a
> series of low-level commands that Tom Clark, K3IO, included in the
> spacecraft design during construction. One of these commands allows an
> uplink receiver to be directly tied to a downlink transmitter. The
> twist is that the uplink is regular FM, but the downlink via the BPSK
> transmitter is DSB (Double Sideband). Mark placed the satellite in this
> mode early this week and did some testing."
>
> Glasbrenner also said the satellite hears very well; the reduced
> bandwidth by using either USB or LSB on the ground station receiver
> "allows for a very robust downlink. Tuning the downlink is just like on
> a linear transponder, meaning it is tight and with fast Doppler. Uplink
> tuning is not required, just as with the FM mode V/U satellites. My
> personal observations include being able to access and hear the
> satellite within one degree of the horizon, much lower than any other
> current bird for my location [in Florida]. This should be an easy
> satellite with omni antennas and a 70 cm preamp."
>
> Glasbrenner said that he would like to open the satellite to general use
> for a test period. The uplink is 145.920 MHz FM, and the downlink is
> 437.026 MHz SSB +/- Doppler shift. He asks that users restrict their
> uplink power to a reasonable power level, and do not transmit without
> being able to hear the downlink; all general single-channel guidelines
> apply. Please submit reports via e-mail at, [log in to unmask] "Enjoy
> this bird's new life!" Glasbrenner said.
> NNNN
> /EX
>
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