40-m Domestic Propagation at November 2022 at FT8 QSO Party in Japan

Social experiment FT 8 QSO party” was held on 2022 Nov. 13 09:00- 24:00 local time in Japan. It was a contest type competition, and all contact data were required to submit. These data were opened to public for analysis after removing critical personal information. In addition to the ordinal contest, the visualization contest of propagation analysis was held. Objectives is a creation for digital transformation of amateur radio. Specifically, we can enjoy a contest without transmitting. It is aimed to create an innovation. Supplementary prize was sponsored by ICOM corporation. 29 amateurs submitted their logs, and the number of unique stations is 93. They logged 722 contacts including both side records  During the party, most of the contact done by 40 m, since it is most suitable band for domestic contact, as the same as 20 m band in US. Python Pandas, CERN ROOT and Microsoft excel were used as analysis and visualization tool. Since difference of signal report in one contact is caused by the transmission power different. Scatter plot of stronger and weaker signal in single contact was made. Most of the contact were done within 10 dB difference, however maximum difference was 40 dB. It is recommended to reduce power when one has larger difference than 10 dB. All contacts were recorded with grid locator and physical propagation distance of each contact was calculated with assuming 200 km altitude of F2 ionosphere layer. Minimum distance was 400 km. The time dependent of propagation distance distribution was made. It seems that F2 layer was activated most from 10 to 12, since distribution peak was at minimum distance. After 13:00 JST, its peak moved to longer distance. We intuitively could recognize tendency of propagation change during operations, this type of visualization may help to understand propagation trends.