St. Helena Island is an amazing location for temperature inversions. The radiosonde data for St. Helena shows the evidence of remarkably strong and stable temperature inversions during the southern hemisphere summer.
History
The first indications of the incredible DX potential from St. Helen Island came to light in January 2008. I was considering operating from the west coast of South Africa on a business trip planned for February 2008. Although that operation did not come to pass, it started the process of examining the South Atlantic pasth in greater detail. Several attempts to contact operators and SWLs in Angola and the Democratic Republic of Congo to alert them to listen for FM stations from Brazil did not bear fruit. I wondered if anyone on St. Helena might be interested in listening for African and South American stations.
Somehow I established contact with John Turner on St. Helena. John at the time worked part-time at the St; Helena FM radio station, Saint FM. John started listening and within a few days reported hearing an FM Broadcast station from Angola. A few days later he logged Namibia, followed by Springbok, South Africa and then many stations from the Cape Town area. One afternoon in late February he logged 25 stations in a cumulative 30 minute listening period. All this reception was on his car radio. Signals were received on approximately 50% of teh days in January and February. 2008.
Beacon
It became very obvious that the strong and regular ducts would be excellent for working the path between St. Helena Island and South Africa's west coast. The biggest obstacle was a lack of suitably equipped and interested operators on St. Helena. That made it a great candidate for one of the simple beacons. A beacon was manufactured in mid-2008. It is currently complete and awaiting shipment to St. Helena as soon as a suitable location is found.
2008/2009 season
Tropo ducting returned to St. Helena Island in November 2009. Reports early in the month came of FM broadcast stations being received from both Africa and South America. John Turner had been joined in his efforts now by Bruce Salt ZD7VC. They reported one November day that they were not able to identify an Angolan FM station because of QRM from a Brazilian station. They also passed along reports of 156 MHz marine band stations in Walvis Bay, Namibia, being picked up full quieting by the meteorological station on the east side of St. Helena