Monday, February 13, 2023

15,700km opening on the 40 MHz band between Ireland and Australia - 12th Feb 2023


12th February 2023: With the solar flux just above the 200 mark, some interesting paths are beginning to appear on the 40 MHz (8m) band. On the 12th of February 2023, Lloyd, VK4TVL in the north-east of Australia received the FT8 signals on 40.680 MHz from Tim, EI4GNB and Robbie, EI2IP in Ireland.

 Txmtr Band Mode Distance Time (UTC) SNR
EI2IP 8m FT8 15766 km 11:11:44 -16
EI4GNB 8m FT8 15587 km 11:00:14 -17

The signal reports of -16dB and -17dB suggest that the signals were very weak indeed and just below what is really audible to your ear. It is however stronger than what would be required for a successful FT8 contact.

Lloyd reports using an off-centre fed dipole for the 80m band up about 6-metres. No doubt with a dedicated antenna for the band, the signals would have been even stronger.

Analysis... This opening happened just after sunset in NE Australia and that no doubt was a factor in the opening. The primary mode of propagation was likely F2 with possibly some help from TEP to the north of Australia.

The distances of 15,587 kms and 15,766 kms are the longest paths that have been reported on the 40 MHz band so far for amateur radio or experimental stations. Could it go further?

The next obvious step is for someone down around Sydney & Melbourne to receive the 40 MHz DX signals. Even though it's about an additional 1000kms or so, the path is a little more southerly so the chances of success are high.


New Zealand to Europe on 40 MHz??? The problem here is that the short path and long path start getting close to the polar regions. This is especially true for stations in the UK or Ireland.

The path above shows the path from the centre of England to the north tip of New Zealand. i.e. location of ZL1RS. The path from Ireland is even worse. From the UK, the SE of England looks like the best spot i.e. G9PUV.

Perhaps a 40 MHz path from New Zealand to the OZ7IGY beacon in Denmark or the stations in Slovenia or Croatia might be more likely? The short path and long path routes certainly don't get as close to the poles.

Link: For more information on the 8m band, visit my 40 MHz page.

1 comment:

Robbie Ei2iP said...

Thanks for the heads up on the propagation to ZL, sure all we can do it try, I think to date we have surpassed expectations of what propagation there is on 40Mhz, the more people we have active, the better the chances.
A big thank you, to all the SWLs that email or post reports, it really helps with the experiments on 8M band.

De Ei2iP, Robbie.