[amsat-bb] Roving, Records, Mountains and Mechanics

[Dave Swanson]

Hello Satellite Friends and Colleagues,

As promised, here’s a better written summary of my adventures recently. 
Far warning, this is a long post.

EM24/EM25 Portable Operations:

Over the Labor Day weekend I traveled to far western Arkansas for some 
fun in the mountains and to see some family. The area is quite rugged 
and has several of the highest points between the Rockies and the 
Appalachians, and is also very RF quiet, therefore it’s a wonderful 
place to operate on all bands. I operated 12 different passes over the 
course of 3 days, and made 62 QSOs to 7 different DX entities from 2 
different grids in both Arkansas and Oklahoma. I know I handed out new 
WAS and VUCC contacts to lots of people as well, which is a blast. 
Everything should be in LOTW now, and I will happily QSL direct if you’d 
rather have a card, just shoot me an email. Thanks to everyone who 
worked me.

AO-7 Contact with EA5TT:

The highlight of the trip was setting a new distance record contact with 
Manuel Carrasco, EA5TT, on AO-7(B). After the FO29 record contact with 
F4CQA a couple weeks back, I was encouraged by Wyatt, AC0RA, to try and 
break his record contact with Bill, OM3BD, of 7903.55km on AO-7(B). 
Using a compiled list of known AMSAT operators in Europe, I began 
running distance calculations to see who would be in that ‘sweet spot’ 
range of 7900km-7950km from my home mountain in EM34. No stations fit 
the bill, even with minor adjustments of me operating from other 
mountains in the area, so I had to start thinking larger. Rich Mountain 
is the 2^nd highest point in the state of Arkansas, and a few hours 
drive to the west of the QTH. I’ve operated Summits on the Air from 
there many times, and it is a popular tourist destination in that part 
of the state. Many of the mountains in this part of the country and 
large, flat, and heavily forested on top, which makes getting a good 
view of the horizon difficult, even from altitude. Rich Mountain is 
unique in that there is an old US Forest Service fire tower on top, 
which is open to the public on Saturdays from 12:00PM to 4:00PM. I 
decided to run distance calculations from this spot, seeing if it would 
make a difference, and low and behold it did.

Manuel, EA5TT, is a twitter friend and we’ve talked about trying to make 
a Satellite contact before, but the extreme distance would make it 
difficult. From his QTH to the Fire Tower on Rich Mountain was 7947km, 
which was in that ‘sweet spot’ of beating Wyatt and Bill’s record, but 
still possible according to the math. I was also hoping the extreme 
altitude would assist in ‘extending’ the footprint enough to make the 
calculated 51 second window a bit longer. The final puzzle piece was 
finding a pass that would fit into the Saturday, 12 to 4 window, where 
the Forest Service would let me into the tower. As luck would have it, 
that following weekend had just such a pass, where both Manuel and I 
would have a very brief window, and contact should be possible. I got 
permission from the XYL, crossed our fingers the weather would be good, 
and the Friday night before I headed west. Everything seemed to fall 
right into place on the day of the contact and we successfully completed 
the QSO at 1812 UTC time. Several other hams were on the pass, Drew, 
KO4MA, John, K8YSE, and Mike, KC9ELU, and all heard it happen. I’m 
actually very grateful for KC9ELU standing by when he heard me get into 
the bird when I did, so Manuel and I could complete the QSO before his 
LOS. I know he missed a solid contact because he chose to standby, and 
it was the true epitome of the Ham spirit to let us grab the record at 
the cost of his own QSO. I hope him and Manuel can hook up again on an 
AO-7 pass very soon.

I did finish my ‘edited’ video of the contact, with commentary, the 
story, and some more data last night and have uploaded it to YouTube here:

https://www.youtube.com/watch?v=-SXucDNddYE

I hope I’m doing the hobby proud with my contributions and storytelling. 
I’m a little rusty at video editing, and I’ve had to switch to an 
entirely new software suite, but I think I’m slowly getting the hang of 
things again.

General Portable Satellite Operations:

I have promised Red, KC4LE, and Amsat Journal article on portable 
operation, so I won’t spill too much here, other than to encourage 
more.On Monday I worked G4DOL in IO80 from EM24 with both of using 
Arrows, standing outside in the 7200km range. Just yesterday I heard 
Drew, KO4MA, using an Arrow and an 817 work George, MI6GTY, using an 
Arrow and an 817 at around 6600km. The point is you don’t have to have 
massive automated stations with 50 elements to work low passes and grab 
DX. Clayton, W5PFG, has extensively tested portable antennae out on the 
high plains, and has tons of data showing that they work AOS til LOS 
with a clear view of the horizon, and I think I’ve proven beyond a 
shadow of a doubt these past two weeks, that if you get up nice and 
high, the portable antennae can compete with even the biggest of home 
arrays, when it comes to grabbing DX. Get out of the shack, go somewhere 
with good visibility, and point your antenna at the horizon. I bet 
you’ll be amazed at what you hear.

Mechanics of Elevation:

This is another topic I’ll be trying to get into journal format, but I’m 
still needing assistance in interpreting some of the data I’ve 
collected. John, K8YSE, in particular mentioned that during the AO-7 
pass he started hearing me when the bird still should have been almost 
2° below the horizon at my location. After watching my recorded videos 
of these low elevation Satellite passes, and timing AOS til LOS, I can 
confirm that the math seems to indicate the higher you go, the longer 
visibility you have, but just elevation doesn’t tell the whole story. 
The FCC has a term they call ‘Height Above Average Terrain’ (Thanks to 
Clayton, W5PFG for telling me about this) and is used for placing 
transmitters and repeaters, and estimating coverage area. This value 
seems to be much closer to relevance in estimating the actual time you 
can see a bird from a particular location, then just pure elevation. 
Anyone that has experience using this value in real world scenarios, I 
would interested to talk with you offline.

If you’ve read the whole thing to this point, thanks for sticking in 
there. It’s a pile of information I know, and appreciate you taking the 
time. I’ve been having a blast recently, and wanted to share with you 
all what I’m up too. Until next time, catch you all on the birds.

73!

-Dave, KG5CCI