Saturday, November 10, 2018

2700km contact made on 2m from South Africa to St.Helena Island

It was announced on Southgate Amateur Radio News during the week that a contact had been made between South Africa and St.Helena Island on 145 MHz.

"Kobus van der Merwe, ZS3JPY reports that between 19:45 and 21:45 UTC on Wednesday 7 November 2018, a QSO took place on 2 metres between St Helena Island and the West Coast of the Northern Cape. A distance of 2,740 km.

The QSO was on 145,500 MHz FM using a vertically polarised antenna between Garry Mercury, ZD7GWM and Kobus ZS3JPY and Michelle ZS3TO van der Merwe in Kleinzee as well as Cobus van Baalen, ZS3CVB in Port Nolloth.

They did try a QSO on 70 cm, but the signals did not provide for a successful QSO. "

This is a recording of the contact...

Info from Facebook..."From ZS3JPY Kobus: Qso with ZD7GWM with ZS3JPY Kobus, ZS3TO Michelle 2777km and ZS3CVB Cobus 2740km on vhf 145.500 Fm simplex with Vertical antenna 07.11.2018 qso started 21H45 until 23H45 we even tried 70cm and we nearly made a contact but signal just not good enough we will try tomorrow evening. ZS3CVB qso with Gary ZD7GWM on St Helena Island vhf Fm mode and 50w both sides
Gary: ☓520 dual band Diamond antenna;
ZS3CVB: X700H dual band Diamond antenna explorer the vertical antenna and use quality low loss coax Cable.

Me and Cobus were having our evening qso on 145.500 and Gary called in and Cobus ZS3CVB said somebody is breaking in and iam jumping up and down screaming to Michelle: St Helena Island is calling in on the frequency!"

This was a really good contact especially as it was on FM as opposed to SSB, CW or FT8. The tropo forecast for the area shows very good conditions off the west coast of Namibia so the propagation mode was probably marine ducting.

How does this compare to other contacts made on the 2m band? This is the equivalent distance of 2740kms from the South-West of Ireland.

It almost reaches across the Atlantic to Newfoundland. However, it's also the same distance from Ireland to the Canary Islands off the west coast of Africa.

Most years, we have openings from Ireland and the South-West of the UK to the Canary Islands (EA8) via marine ducting tropo. It's unusual but not rare.

I suspect that the contact from South Africa to St.Helena is pretty much the same, unusual but not rare. If anyone looks at the topography of St.Helena then they can see that the populated area on the north-west of the island is blocked to the south-east by hills. ZD7GWM is in the centre of the island with a better take off and perhaps this is what made the difference. When similar ducting happens again...and it will, another contact may well be possible.

Is a contact possible from South Africa to South America. The distance is about 5800 kms, over twice the distance of the South Africa - St.Helena contact. Unlikely.

Although I seem to remember a news item from a few years back where someone in Namibia did tests on 2m with someone in Brazil?

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