since Aug. 31, 2011

◆　Introduction　 ◆


I would like to express my deepest sympathy to all the people who suffered from the Great East Japan Earthquake and Tsunami that hit northeastern Japan on March 11, 2011.

As the title of this WEB site implies, an efficient use of solar power as a safe natural energy source and the detection of seismic electromagnetic phenomena by the use of FM tuners are being pursued.

Newest waveforms of reception signal levels of radio broadcast waves from distant FM radio stations, that are continuously observed at Yokohama city, Kanagawa Pref. Japan, are shown in a graph in the page under menu "Newest Reception Signal Levels." 　

system's appearance　

After the last upload of the detected signal levels (June 30, 2008) on a WEB page that existed prior to this page, efforts have been made to improve the stability and the accuracy of the reception systems for about three years.  Recently, I have completed the building of a pair of FM tuners and a pair of 4-20mA voltage to current converters (shown above) that together constitute two reception-transmission systems. Detection signals obtained by these systems are transmitted, via transmission cables, to a data logger (a combination of a D/A converter hardware and a software running on a Note type PC) that is installed in a  different place in the house in order to avoid interferences.
It is reported that extraordinary propagation of radio waves (VLF) occurred shortly before the Great Hanshin Awaji earthquake on January 17, 1995 (According to a book on Earthquake Prediction edited by professor Toshiyasu Nagao).
It is also reported that  before M9 Great Tohoku earthquake, the total electron content of the ionosphere increased dramatically over the epicenter, reaching a maximum three days before the quake struck (according to May 18, 2011 MIT Technology Review).
Although the continued observation of FM radio waves may not directly lead to "earthquake prediction", I think it is worthwhile to monitor the changes in reception levels of FM radio signal waves transmitted from distant radio broadcast stations in order to find a clue to the study of the electromagnetic seismic phenomena.

It has been discovered that disturbances to the observation of radio waves in an urban (highly populated) area  due to electromagnetic noises from various appliances are not so critical as usually believed.
In the system currently operating, radio waves of different two frequencies are observed concurrently in order to facilitate the differentiation between the reception signal and noises.  (Uploaded in 2013, and restarted in March 2019)