[amsat-bb] Falconsat-3 and APRS HT's?

Patrick STODDARD (WD9EWK/VA7EWK) amsat-bb at wd9ewk.net
Sun Oct 1 18:30:12 UTC 2017

Hi Bob!

There are more than a few of us who have tried FalconSat-3 with
the HTs capable of 9600bps APRS. The TH-D7 and TH-D72 are probably
the best HTs for this, as they are capable of full-duplex operation.
I have used my TH-D72 to make a few QSOs last weekend, and I have
also used other combinations of radios to get on these passes...

1. TX: TH-D74, RX: another TH-D74
2. TX: TH-D74, RX: TH-D74 and SDRplay with HDSDR & UZ7HO's
3. TX: TH-D74, RX: SDRplay with HDSDR & HS-SoundModem
4. TX: TH-D74, RX: SDRplay w/HDSDR, HS-SoundModem, UISS

With all of these radios and combinations of radios, I have been
using my Elk Antennas handheld 2m/70cm log periodic, going through
a 2m/70cm diplexer whenever I'm using more than just the TH-D72.

For a few of these passes where I used the SDR receive setup, I
have made RF recordings. Using the UZ7HO or UISS programs, I am
also making logs from each program. For just the HT, pictures of
the HT's screen showing the messages exchanged with other stations
and other information like position packets. I have posted files
in my Dropbox space at http://dropbox.wd9ewk.net/ (look for folders
with "FalconSat3" in the folder names).

I just tried the 4th setup listed above for the first time on the
1756 UTC pass this morning. As I've seen before, I am receiving
more data with the SDR setup than with the HTs. I saw my own packets
passing through the digipeater - my position/comment packet, as well
as a couple of messages sent to ALL. I haven't tried using the
software directly to a radio, but I have a SignaLink USB here, and
may work on that. The SDRplay, along with HDSDR's AFC function,
works very well on the downlink. I normally don't have to make any
adjustments to the downlink frequency during passes, as long as I
am reasonably accurate in pointing my antenna skyward. UISS makes it
easier to keep track of call signs, rather than just looking at the
HS-SoundModem window - especially when a burst of packets show up on
the screen, and I might miss something as it scrolls off the window.

I have two more really nice passes this afternoon - 1935 and 2115
UTC. I am going to use the same setup on those two passes, and hope
to see other stations using the digipeater like me. Maybe I will add
to my short list of FalconSat-3 QSOs (currently at 3)...


Twitter: @WD9EWK or http://twitter.com/WD9EWK

On Sun, Oct 1, 2017 at 3:20 PM, Robert Bruninga <bruninga at usna.edu> wrote:

> I was confused.  I thought FALCONSAT-3 was a PACSAT protocol store and
> forward system because I thought I saw people trying to get the old PB and
> BG code,  But the AMSAT web page says it is 9600 baud GMSK up and down.
> https://www.amsat.org/falconsat-3/
> 435.103 MHz down and 145.840 up DIGI call of PFS3-1.  While of course
> setting 5 memores to chase the Doppler the full 20 KHz during the pass.
> So I am surrprised that I havent heard of anyone making contacts with any
> ole' APRS HT or Mobile...  All of these radios can do 9600 baud and APRS
> natively..
> Im under Kitchen arrest until 1st grandkid arrives soon and cannot play.
> If I missed something, ignore me.  Ill go back under my domestic rock...
> Bob, WB4APR

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