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<font face="Arial">Last August, September and October, I drove a
combined total of 11,500 miles (18,500 KM) on three separate road
trips. </font><font face="Arial"><font face="Arial">I was
operating 30M HF APRS on both classic AX.25 and on APRS
Messenger digimodes from my VW Jetta TDI during all three trips.
<br>
<br>
</font>The first one starting in late July was from central
Michigan (where I now live) to Los Angeles via Denver, Colorado
& the annual Evergreen Jazz Festival. I then continued up the
west coast to Sacramento, before returning via Lake Tahoe, Carson
City Nevada and a day's portable operation from 14,500-foot (4400
M) Mt Evans west of Denver. <br>
<br>
The second one was from central Michigan up the St Lawrence seaway
on the Canadian side (Toronto, Montreal, Quebec City) clear to
Cape Breton (the far eastern tip of Nova Scotia) and Halifax,
before returning on the US side via Maine, New Hampshire and
Vermont for the fall colors. <br>
<br>
The third one, departing in early October only two days after I
got back from Canada was from central Michigan to the town of </font><font
face="Arial"><font face="Arial">Olive Branch in the</font> far
northwestern corner of Mississippi, just outside Memphis,
Tennessee. This was for a 40-plus-year reunion of the personnel of
AFVN (American Forces Vietnam Network radio-TV. (I literally
lived the real-life "Good Morning, Vietnam" serving with AFVN
1969-1970 at the peak of the Viet Nam mis-adventure.)<br>
<br>
This fast-blast 3-day trip (One day/750 miles/1200 km down, one
long day on the ground, and the third day/750 miles/1200 km back)
was to present my collection of several hundred Kodachrome slides
of AFVN facilities at the event. I had scanned them into quad-HD
resolution TIF images that were then displayed with a gorgeous
brand-new Panasonic quad-HD projector another attendee provided.
In the course of the event, a Skype video call was placed to an
AFVN veteran in Alaska who couldn't attend in person. You can't
imagine how amazing a 1080p webcam looks thrown onto a 25-foot
(7.5 meters) diagonal screen! All done with the Panasonic
Toughbook I normally use as my mobile APRS and mapping platform. <br>
<br>
During the course of these three trips, I was running both the
UZ7HO Sound Modem for 300 baud AX.25 packet APRS, and APRS
Messenger for PSK63/GMSK/MFSK16 APRS simultaneously using the iMic
USB sound system and my FT-857 & W6HIQ screwdriver. I was on
the air nearly continuously while driving, except for brief forays
onto 20 and 15 meter SSTV. (The N2VZ totally-automatic
screwdriver controller is marvelous, encouraging far more quick
QSYs across bands due to it's totally effortless just
recall-a-memory-channel, hit-the-tune-button and sit-back
operation.) <br>
<br>
The level of activity on the 10.149.700 APRS Messenger channel was
significantly lower than I have experienced in previous year's
trips. However the contacts I did make again dramatically
demonstrated how much more effective </font><font face="Arial"><font
face="Arial"> the PSK63 and MFSK16 modes are</font> than classic
300 baud packet APRS. Numerous times in the boondocks with no
VHF APRS whatsoever, but with Internet connections available at
McDonalds, motels, etc, I was able to monitor myself on findu.com
for APRS.fi. I use a mag-mount mobile 2.5 GHz collinear gain
whip to make WiFi connections at these places from inside the car
while discretely parked at the far edge of the parking lot (or
even across the street!) while popping off position beacons on the
HF rig. If that fails, I have a 14-dBi 1-foot-square WiFi panel
antenna with a USB WiFi dongle stuck to the back (only 6" coax
from the dongle to the antenna) mounted on a table-top tripod.
With this "WiFi Superblaster" resting on the roof of the car (or
pointed out a motel window), I can easily use WiFi hotspots from
three or four blocks away. <br>
<br>
[Once again kudos to the State of Iowa for providing free WiFi at
EVERY Interstate highway rest stop. They use a 10-foot fiberglass
collinear 2.5 GHz stick on the roof of the rest area building to
provide solid coverage of the entire rest-area parking lot -- you
can use it from inside your car without going into the building's
lobby. Iowa spaces the rest stops every half-hour along I-80
(E/W) and I-35 (N/S). This means you are never more than about 35
miles/55km from guaranteed Internet access anywhere on the 600
miles/965 km of Interstate highway in the state. Further, this
year WiFi is more ubiquitous than ever. Most of the fast-food
chains (Burger King, Wendy's, Taco Bell, </font><font
face="Arial"><font face="Arial">KFC, </font>Taco Johns, Culvers,
etc -- not just McDonalds & Starbucks) are now offering WiFi
in most of their properties. As are more and more chain
full-service restaurants like Dennys, Ihop, Olive Garden, Perkins
Pancake House, etc.] <br>
<br>
Many times I wouldn't reach the APRS-IS at all on AX.25 packet,
but would on PSK63 despite the far fewer number of igates
operating on Messenger modes. When PSK63 wouldn't get heard by
an igate somewhere out there, I would switch APRS Messenger to the
MFSK16 mode. This multi-tone low-symbol-rate FSK mode is
unbelievably effective at low signal levels. It can detect and
work reliably with signals that are inaudible in the radio's
speaker! <br>
<br>
Almost invariably, MFSK16 would get through on the first try when
NONE of the other modes would. I experienced only 4 failures to
reach the APRS-IS on MFSK16 in hundreds of tries on all three
trips. It's absolutely amazing and just begging to be used in the
field with low-power "porta-luggies" like the FT-817. The only
downside to MFSK is that it is much slower than other modes - a
beacon that would take about 1.5 seconds on 300 baud AX.25 takes
about 5-8 seconds on PSK63 and about 20 seconds on MFSK. But
then really low bit rates are how NASA is still getting data back
from the 35-year-old Voyager probes that are now outside the solar
system. <br>
<br>
Note that the current versions of APRS Messenger sound-card
application has built-in igate functionality if you have an
Internet connection. Further, regardless of which TRANSMIT mode
(PSK63, GMSK or MFSK16) you select, it will automatically RECEIVE
all three modes and igate them if they pass checksum. <br>
<br>
<br>
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<hr size="2" width="100%"><font face="Arial"><br>
--<br>
<br>
Stephen H. Smith wa8lmf (at) aol.com <br>
Skype: WA8LMF<br>
Home Page: <a class="moz-txt-link-freetext" href="http://wa8lmf.net">http://wa8lmf.net</a><br>
<br>
High Performance Sound Systems for Soundcard Apps<br>
<a class="moz-txt-link-freetext" href="http://wa8lmf.net/ham/imic.htm">http://wa8lmf.net/ham/imic.htm</a><br>
<a class="moz-txt-link-freetext" href="http://wa8lmf.net/ham/uca202.htm">http://wa8lmf.net/ham/uca202.htm</a><br>
<br>
Vista & Win7 Install Issues for UI-View and Precision Mapping<br>
<a class="moz-txt-link-freetext" href="http://wa8lmf.net/aprs/UIview_Notes.htm#VistaWin7">http://wa8lmf.net/aprs/UIview_Notes.htm#VistaWin7</a><br>
<br>
"APRS 101" Explanation of APRS Path Selection & Digipeating <br>
<a class="moz-txt-link-freetext" href="http://wa8lmf.net/DigiPaths">http://wa8lmf.net/DigiPaths</a> <br>
<br>
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