[amsat-bb] PSAT- transmission sequence

[Robert Bruninga]

PSAT PSK31 is always in AUTO mode.  It will come up whenever it hears PSK31
on the 28.120 uplink.

Bob, WB4APR

On Wed, May 27, 2015 at 9:54 AM, David G0MRF <g0mrf at aol.com> wrote:

> Congratulations Bob and USNA on another successful spacecraft.
>
> I listened for the first time this morning and could hear the beacon and
> transponded PSK31 without any trouble.
>
> But I was not expecting the 435.350 carrier to stop every now and again.
>
> What determines if the carrier is on or off. - Beacon timing.- OK, but is
> the transmitter also PSK activated in someway? Or is it a timer.
> Very nice for saving power.
>
> Thanks
>
> David  G0MRF
>
>
> -----Original Message-----
> From: Robert Bruninga <bruninga at usna.edu>
> To: AMSAT BB <amsat-bb at amsat.org>
> Sent: Sun, 24 May 2015 17:58
> Subject: [amsat-bb] PSAT Status (day 4)
>
>  PSAT  PSK31 435.350 MHz FM downlink is full quieting with 6 bars using a
> decent
> UHF Yagi.
>
> But we have not seen any users other than those using the 28.120
> PSK
> channel on HF normally.  We welcome people to experiment with it.
> Everyone
> within the 28.120 to 28.123 MHz ten meter passband will be
> uplinked and heard
> on the 435.350 MHz downlink.
>
> The Naval Academy's PSAT seems healthy with
> plenty of power (we are
> keeping the APRS digipeater off to allow max power for
> PSK31).
>
> PSAT 's radio and packet system are a simple $250 APRS
> trackerhttp://www.byonics.com/mtt4b sent to space.  The PSK31 transponder is
> a
> single 3.4" square circuit board made by Brno Universtiy in the
> Czech
> Republic.  The CPU for controlling bulletins and timing is a
> simple
> Parallax Basic Stamp.
>
> PSAT is actually only about a 1U cubesat but in
> a 1.5U package since the
> flight was available and it gave us more power for our
> NON-SPACE solar
> cells.  We are using standard silicon that are only half as
> efficient as
> multi-junction cells, but only cost 1% as much.
>
>
>