Transequatorial propagation on four metres

I mentioned in a previous post that I had a brief chat with Dick ZS6BUN over dinner at the RSGB Convention. He talked about VHF activity in South Africa and we each have an IC-9700. informs us that he is interested in weak signal work at VHF. Dick touched on the subject of TEP on six metres. Of course, not everyone at the table was into VHF so it was only a brief conversation on the subject.

In one of the 70 MHz groups to which I belong, someone drew our attention to a quote from the RSGB website:

“For some years stations in South Africa (ZS) have had a 70MHz allocation. The 9000km path between the UK and South Africa is particularly interesting as both ends lie at the extremity of the trans-equatorial zones. A contact over this TEP path is quite possible around Sunspot maximum and should take place when conditions are particularly good on the 50MHz band. Possible openings between the UK and South Africa will probably occur during the month of October.”

I am a newcomer or at least very late returner to 4 metres; I have limited experience and 50 watts to a quarter-wave vertical. However, I am very much interested in VHF propagation and was surprised by the comment about TEP on 70 MHz as far as the UK is concerned.

I emailed Dick in South Africa to ask him if he had any knowledge about this. He replied that he worked TEP on 50 MHz but was not equipped for 70 MHz However his friend Willem ZS6WAB is active on four metres TEP and has been for quite a long time. This was useful information and set me on the trail to find out more.

It turns out that Willem has worked into Europe on 4 metres and it looks as though he is the SSB record holder for distance although there is one longer into Italy via ISCAT. So there have been TEP QSOs between South Africa and Rome and to Mallorca.

What I cannot find is any reference to 70 MHz TEP QSOs further north in Europe, and apparently not to UK.

I would welcome any additional information. It is just conceivable that UK – South Africa contacts at 70 MHz could be made via TEP and some other mode of propagation, maybe very enhanced tropo, even Sporadic E, but both SpE and TEP are seasonal (SpE around the solstices and TEP around the equinoxes) so they may not coincide. TEP is apparently via chordal hop relying on two reflections via the F layer without an intervening ground reflection. One of my correspondents has suggested that the “geometry” may not be right for contacts beyond around 7,500 km on four metres. Has that distance been exceeded? I do not know.


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