Good evening,
This was my first year running the AMSAT demonstration station at the Dayton Hamvention after Keith Pugh, W5IU, had run it for many years. After volunteering at the demo station the past couple of years, I knew what to expect: a poor horizon to the north (due to the arena), high levels of RF (including lids running FM simplex inside the satellite subband on 2m), and lots of fun demoing satellite operation to curious newcomers as well as meeting many satellite operators I've worked on the satellites in person.
The core of the demo station was similar to past years. I brought my pair of Yaesu FT-817s (known fondly among many satellite operators as a Yaesu FT-1634) as well as a Windows 10 tablet and a FUNcube Dongle Pro+. The antenna was an Arrow II 146/437-10BP and I also brought a cheap Optera camera tripod. In addition, John Papay, K8YSE, brought his Icom IC-910H, laptop, and Arrow antenna on a speaker stand with a mount that allowed a smooth way to change polarity throughout the pass. With this mix of equipment, we were able to demonstrate several methods of satellite operating: computer controlled Doppler tuning of a transceiver designed for satellite operating, manual Doppler tuning with a pair of VHF/UHF all-mode transceivers, and use of an SDR receiver with a VHF/UHF all-mode receiver for full-duplex operating on linear transponders.
The demo area was up and running by the time the outdoor areas of the Hamvention opened at 8:00am on Friday morning. Our first pass was an XW-2A pass at 8:17am, with K8YSE operating his IC-910H and KD8CAO running the antenna. The demos were generally a two man operation with one operator at the radio and one serving as the antenna rotor. After this pass, we listened to the 70cm PSK31 signal from NO-84 and a few packet bursts from the ISS using the FUNcube Dongle Pro+ and Windows 10 tablet before a pair of AO-85 passes and an XW-2F pass operated by K8YSE.
By special request, the AO-73 transponder was activated a day area and was available for Friday morning's demos. I operated the 10:51am pass with my pair of Yaesu FT-817s. A video of this pass is available on the AMSAT North America Facebook page: https://www.facebook.com/groups/7828379515/permalink/10154235785829516/
Later, I operated an SO-50 and FO-29 pass with that pair of FT-817s as well, but had to fight strong desense. After those two passes, I grabbed a diplexer I had brought and placed it on the 2m transmit side (to filter out the third harmonic from the transmitter) and experienced no further desense problems with my setup. PY5LF captured part of the SO-50 pass on video: https://www.youtube.com/watch?v=wVPb1a9NqxQ K8YSE then operated the rest of the FO-29, AO-7, and SO-50 passes that afternoon.
On Saturday morning, we opened with listening (and decoding a bit) to the PSK31 beacon on NO-84. Unfortunately, we did not have HF transmit capability. The signal from NO-84's PSK31 transponder is very good and I highly recommend anyone who can transmit on 10m at 25-50 watts and receive a 70cm FM signal give it a try.
After working an XW-2F pass with the pair of FT-817s, I decided to give the SDR receiver a try and made one QSO each on XW-2C and XW-2A using the SDR as a downlink receiver. This was the first time I had tried doing this and it was fun, though I definitely need some more practice with it! I also tried the SDR receiver on AO-73 and FO-29 and made a couple of QSOs.
Shortly after the ARRL Youth Forum ended around noon, a large crowd began to arrive at the demo area. Nine-year old Hope Lea, KM4IPF, who had given a talk at the Youth Forum operated a pass of SO-50 around 12:19pm and made many QSOs from coast-to-coast. A video of this pass is available from the AMSAT North America Facebook page: https://www.facebook.com/james.g.lea/videos/10154297928734363/
After the SO-50 pass, we made several QSOs on FO-29 and then listened to the SPROUT digitalker. The SPROUT digitalker is generally active on Saturday passes. A video of this pass is available here: https://www.youtube.com/watch?v=4FRNZkMb5yM
K8YSE then operated the Saturday afternoon passes of FO-29, AO-7, and AO-85 with his Icom IC-910H setup. Highlights included several of us passing around the microphone to work Paulo, PV8DX, in Brazil.
We got an early start on Sunday morning, operating a pass of AO-85 to the northeast using my dual FT-817 setup just prior to 8:00am. Although I was the only person in the demo area, I made three QSOs on AO-85, holding the antenna myself and leaning over the table to operate the radio. After this, I operated a pass of XW-2F around 8:30am. For the 8:44am XW-2A pass, ARRL Media & Public Relations Manager Sean Kutzko, KX9X, took the microphone and made several QSOs on that pass while I pointed the antenna. Although I did have a tripod for the antenna, I was simply using the stock camera tripod mount and had no way to adjust polarity. Since polarity is so critical while operating satellites, the operators who pointed the antenna while using my Arrow generally took the antenna off the tripod and held it in their hand for quick polarity adjustments. K8YSE's speaker stand mount demonstrated a good way to mount an Arrow antenna on a tripod while retaining adequate control over polarity.
The next pass after this was a low western pass of XW-2C where I made several QSOs. At 9:37am, we operated a pass of AO-85 and made QSOs from coast-to-coast. A video of AMSAT VP of Operations Drew Glasbrenner, KO4MA, at the microphone is available at: https://www.youtube.com/watch?v=xrmzym39X5E
I would note that we were using a pair of FT-817s, barefoot, on that pass and were able to make several QSOs with just 5 watts, mostly full quieting. Though AO-85 can often take a bit more power to get in to, QSOs using 5 watts and an Arrow antenna are very possible.
Passes of SO-50, AO-73, and FO-29 rounded out the demos for the Hamvention and we were QRT at 12:12pm on Sunday, but not before working MI6GTY in Northern Ireland on FO-29. It was nice to get Europe in the log from the Dayton Hamvention demo station and it was our last QSO of the 2016 Hamvention.
The AMSAT demo station has been a fun place to spend a majority of the last three Dayton Hamventions and I would encourage all satellite operators and those curious about satellite operation to visit the station outside of Ball Arena (near the ARRL and AMSAT booth areas) next May. Volunteers and guest operators are always sought!
A few pictures are posted on the AMSAT North America Facebook page: https://www.facebook.com/groups/7828379515/permalink/10154235785829516/ (The AMSAT North America Facebook group is very active - in fact, traffic has likely surpassed the traffic on the AMSAT-BB. If you are not a member, I would encourage you to check it out https://www.facebook.com/groups/7828379515/?qsefr=1)
Thanks to the following for volunteering at the demo station (and apologies if I missed anyone):
Mark Hammond, N8MH Drew Glasbrenner, KO4MA John Papay, K8YSE Doug Papay, KD8CAO Art Payne, VE3GNF Wyatt Dirks, AC0RA Michael Kirkhart, KD8QBA John Brier, KG4AKV Jeff Griffin, KB2M Hope Lea, KM4IPF Sean Kutzko, KX9X
Thanks to the following for providing equipment for the demo station:
Mike Young, WB8CXO (Batteries) Keith Pugh, W5IU (DC power distribution)
73,
Paul Stoetzer, N8HM Secretary, AMSAT-NA Washington, DC
P. S. I did not keep logs at the demo station, though I will remember if I worked you! If you need a card or LoTW upload for EM79, please let me know.