On Sunday the 5th of August 2018, Mark Turner EI3KD managed to work D4Z on the Cape Verde Islands off the coast of of Africa on 144 MHz, a distance of some 4163 kms. This remarkable contact made on CW was a new record for tropo in IARU Region 1. The previous record of 4130 kms was set back in July of 2015.
The contact was made on 144.300 MHz at about 18:26 UTC at a time when the band was also open to the Canary Islands from the south of Ireland and the UK.
EI3KD RIG: 11el F9FT, only at 7m agl or so, RX mast preamp, TX 400W.
EI3KD: 11el F9FT, only at 7m agl, RX mast preamp, TX 400W.
D4Z: IC 275, max 100W, 2 stacked dipoles on 3 directions (omnidirectional antenna), no preamp.
Just to an idea of just how far the new record is, if the same distance of 4163 kms was measured west of EI3KD's location then it would reach as far as Nova Scotia in Canada!
Earlier in the day, the D4C beacon on 144.436 MHz had been spotted at 08:37 UTC by GI6ATZ locator IO74AJ distance 4476km and by GM4ZJI at 16:40 locator IO86KE distance 4739km. The beacon was running just 14W into a stacked dipole array.
D4Z also worked G7RAU and G4LOH in the South-West of England on 2m SSB.
Video of D4Z working EI3KD on 144 MHz...
The mode of propagation was probably marine ducting which is a process whereby VHF and UHF signals can get trapped between the water surface and a layer in the lower atmosphere. The result is that signals can travel over quite far distances and the path from the UK and Ireland down to the Canary Islands can produce some of the longest distances in Europe. On rare occasions, the path can extend as far as the Cape Verde Islands.
Spot on the DX Summit cluster...
EI3KD 144300.0 D4Z 18:26 05 Aug IO51VW HK76MU tnx!!! 4163km Cape Verde
Band Propagation Call a Loc Call b Loc Mode Date Distance
144 MHz TR D44TS HK77KE M0VRL IO70PO SSB 2015-07-09 4130
144 MHz TR M0VRL IO70PO D44TD HK86NO SSB 2011-08-10 4106
144 MHz TR G4LOH IO70JC D44TD HK86NO CW 2007-08-04 4041
144 MHz TR EB8BRZ IL27HK YT3I KN05HP SSB 2009-06-08 3757
144 MHz TR EI5FK IO51RT RW1ZC/MM IK18PQ SSB 2005-08-15 3745
The tropo forecast below from F5LEN shows the path conditions around the time of the contact.
Video of GI6ATZ hearing the D4C beacon...
Links... (Updated 5th Sept 2018)
1) DX spots for D4Z on 144 MHZ
2) F5LEN Tropo Forecast for EI to D4
3) IARU Region 1 VHF DX records
4) EI3KD's website
5) D4C / D4Z website
6) Newsletter from D4C Contest team