RBN / Reverse Beacon Network リバース・ビーコン

Last Monday (local time) was an eventful day for my radio operation, as I saw my call signs in the RBN, Reverse Beacon Network page. I had been aware of the site from a couple of articles in the recent issues of the Japanese “CQ” magazine and a comment in JF1SGH’s blog, but I had thought that weak signals such as mine would not be caught by the skimmers in the network. Therefore, I had seen the site a few times to know what it was like, but had not opened the site when I called CQ’s. It came to my mind that recent increase of the number of lookups of my “QRZ.com” page might be explained by the RBN, and I transmitted on the 15 meter band while I was watching the page for the band.
I was surprised to see my call appear immediately after I started sending CQ’s. The skimmers who caught my signals during morning hours of local Monday were KH6LC, VE6AO, K3MM and WA7LNW.

I tried the system during the evening hours of the same day; the dx skimmers who reported my signals were OH6BG and 5B4AGN.

I was able to know that my signals reached dx locations even though there was no caller. However, I cannot be too optimistic as we do not know how big skimmers are using.  The Google photo of the antenna of K3MM in Maryland, U.S.A is shown below. I am sure average stations are not equipped with such an antenna.

一昨日、月曜日には、はじめてリバース・ビーコンのページを見ながらＣＱを出してみて、当局のシグナルもキャッチされていることが分かり、ちょっと驚きました。このシステムの存在は、ＣＱ誌６月号、８月号の記事や、JE1SGH局のブログで知っており、サイトを見たこともあるのですが、もっと本格的なアンテナの局でなければ、スポットされないものと思い込み、電波を出しながら見てみたのははじめてでした。

コールが無くても電波は届いていることが分かります。当局の強さの信号でも、例えば、8J1SEA/1 とか、WPXハンターには珍となる 7N1xxx/0 とかの相手が興味を持つコールなら、もっと呼ばれるのかも知れません。ただし、IBPのビーコンがアンテナと送信電力に規格があるのに対し、こちらの方は、受信局の設備がまちまちなので、信号がピックアップされたからといって、必ずしも楽観はできません。上のK3MMのアンテナらしき写真が参考になるかと思います。