Pretty Good Test Report on USA pass of ISS at 1834 to 1839 UTC on 27 Oct 2017:
Conclusion, HT's outdoors with whip antennas do not hear as well as we thought and the Uplink is more challenging than we thought. But certainly gave the thrill expected of monitoring the ISS pass with an HT. This was during mid-afternoon class time on a Friday over Maryland with noob operators.
We had 6 radios, One was an Oscar class ground station plus 5 HT's outside. * The Oscar station heard 11 stations (out of 32 packets total) * HT with long dual band whip heard 4 stations * HT with full size 1/4 whip heard 3 stations * HT with long dual band whip heard 2 stations * HT with rubber duck heard 2 stations * HT with arrow heard one (but had bumped radio on 145.830!)
Of the 11 different stations heard by the OSCAR station: * Two were heard 6 or 7 times * One was heard three times * four were heard twice, one using 5W & ELK, one 10W to quad, one 10W to arrow * four were heard once, one was a mobile,
HTs Receive performance: all of the stations heard by the HT's were from the same 5 in the middle of the pass, with none being more than 250 miles away. The other six stations heard by the Oscar class ground station were up to a bit farther up to 600 miles away.
All 5 of our HTs were on the Planned-Test-1-minute schedule and NONE were heard by the ISS(digipeated).
Of all the 11 stations, three of the four heard twice were following the suggested protocol and so were assumed to be on a 1 minute schedule. So, during an 8 minute pass, only got two packets through even though they had modest beams on uplink. Again, probably during the middle of their overhead geometry. But for our 4 minute window, then they had a 50% success rate.
The APRS-IS captured a total of 30 packets during the same time frame that we got 32 and only 2 or 3 were missed by either of us. There were 8 different Igates with four of them contributing 4 to 6 packets and four contributing one or two. All of this data was from the 4 minute pass window from first station heard by the Oscar class station to the last one heard by that station. The APRS-IS of course heard other stations before and after, but the window was only taken during our OSCAR class pass.
The downlink was sparse and it is doubtful that there was too much overload on the uplink, (though we all know that the downlink says NOTHING about what the uplink receiver on ISS is having to deal with). But that could be eliminated if we could get someone in Hawaii to do the same test. Horizon to horizon with a few radios at the same time. On the same 1 minute test schedule.
The students with the handhelds were not skilled operators and so the attitude of the HT's and antennas relative to the ISS track should be considered completely random.
For what it's worth.
Bob, WB4aPR
-----Original Message----- From: Robert Bruninga [mailto:bruninga@usna.edu] Sent: Friday, October 27, 2017 1:17 PM Subject: QIKCOM-1 and ARISS test
We have not heard from QIKCOM-1 but since we asked users to include their Power and Antenna gain and beacon once a minute for these few passes, we are going to finish the day by seeing what we hear from ISS.
We already see a few people giving that data, so we are going to switch our uplink from the path of APRSAT back to the path of ARISS for the remainder of the day. This will give us all an idea of what hits ISS and what does not. I've seen these so far:
WN9Q>CQ,RS0ISS*,qAR,WA8LMF-SG::APRSAT :5w 14el klm cross yagi
KB6LTY-3>CQ,RS0ISS*,qAR,W0ARP-15:=3429.70N/11712.30W- power 20W - 9.2 dbi beam- DM14jl
Attended packets only to end of today's test. Bob, WB4aPR
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Robert Bruninga