When thinking about Field Day, typically hams think of the event in terms of the HF bands, 80, 40,20, 15 and 10 meters. Some clubs include 6 and 2 meters. This year, SLAMS decided to push the log ever so slightly into the UHF-SHF bands. Namely, we decided to operate FD on 1.2 and 10 GHz!
Ron KO0Z operated with the St. Charles Amateur Club (SCARC) set up at Immaculate Conception Parish (ICD) soccer fields in Dardenne Prairie and Herbert AF4JF worked with the St. Louis QRP Society (SLQS) operating from Spanish Village Park near Earth City.
For approximately three months, Ron and Herbert talked about reflecting signals off the communications tower next to ICD. We were inspired by Ben K4QF's MUD paper elaborating on 10 GHz propagation using commercial TV towers. Although our tower is nowhere near as tall as a TV tower, approximately 250 ft as opposed to 1,000 ft, it was still worth a try!
This photo depicts Herbert AF4JF's view of the tower approximately one-third of a mile to the west, just left of the setting sun.
This view is from Ron KO0Z's perspective, approximately 200 yards away. Herbert AF4JF would be northeast of Ron.
Both of us discovered illuminating the top half of the communications tower provided excellent results. Moving our dishes a degree to either side of the azimuth heading towards the tower resulted of loss of signal. SCARC members were impressed to see 3 cm propagation. About 5 SCARC members made two-way contacts with Herbert! Each received a "First Contact Award!"
An even better point source turned out to be the WB9PNU/B approximately 18 miles away to the east. We were copying it 599 off the top half of the communications tower. Ron was unable to copy the beacon pointing his dish towards its location. Too much vegetation. Needless to say, SCARC members were very impressed. So was I and Herbert. We plan to be at opposite ends of the tower and see just how far we can copy each other's signals in the near future. Somehow, I think the STL TV stations TV towers will be next!
The elevation profile between ICD (SCARC FD site) and the WB9PNU beacon is interesting.
After finishing up our demo and FD contacts on 10 GHz, Herbert AF4JF went back to the SLQS FD site near Earth City and Ron KO0Z went to SSM Medical offices near Kisker Road and Hwy 364 near Harvester, MO. The distance between SSM and SLQS is approximately 9.5 miles. Ron and Herbert exchanged 5x9 SSB signals on 1.2 GHz! However, Ron's PTT RCA connector broke a lead and we weren't able to make a 10 GHz Q, but both of us are sure we could have made the 3 cm Q.
The elevation profile between SSM and SLQS is very interesting. SSM is on the far left of the profile and SLQS is on the right. The big "valley/dip" just right of center is the Missouri River. We had two large obstructions between us. Going right from SSM is the Caulk's Hill ridge in Harvester. Further to the right is the Hwy 94/Hwy 364 interchange.
All in all, we had a great time adding microwave contacts to both club's FD logs! Best of all, we experimented with Ben K4QF's MUD findings and met with success! Now, we want to experiment even more with this mode! Evidently uW tower propagation applies equally well in MO as it does in AL! Tnx Ben!
