Long path opening on 50 MHz between South America and Asia - 12th March 2022

12th March 2022: There seems to have been a really good opening on the 50 MHz band at about 01:00 to 04:00 from South America to the east of Asia (Thanks to N0JK on the tip off for this).

The map above from the PSK Reporter website shows the paths as reported for PY2XB in Brazil. The site shows the shortest path between two stations but I think in reality, the contacts from Brazil to Japan & Taiwan were all via long path.

Long Path V Short Path... The map above shows the situation. For someone in the south of Brazil, Taiwan is effectively the other side of the world and there isn't that much difference between short path or long path.

I'm subject to correction on this but I think this extensive opening on 50 MHz was around 21,000kms via the long path.

The map at the start of the post shows that there was a path also from Brazil to Hawaii at 01:58 UTC. The map above also shows where the daylight was at about 03:00 UTC. It was likely that there was strong TEP to the west of South America which likely played a factor in the opening.

This chart is a point to point HF propagation forecast and shows how likely an opening is on each of the bands from PY2XB in Brazil to BV3UF in Taiwan. As you can see, the long path on 28 MHz is very good from 24:00 to 06:00.

By contrast, the short path prediction is very poor at this time. The DX spots just report stations heard but no-one seems to mention short path or long path.

Propagation Mode???... As mentioned already, TEP (Trans-Equatorial Propagation) is likely to have been involved but how much? Was it partially TEP with the rest of the path via F2 propagation? Was there greyline and chordal propagation involved across the Pacific where the sun was setting?

Some seem to be very quick to explain every long distance opening as being simply TEP but remember that we're talking about a path of 21,000kms at 50 MHz. I'd suggest that it's a lot more complex than that.

Just for reference purposes, the solar flux on the day was about 127.

Notes... This was a reasonably good opening between two areas with a lot of 6m activity. The maps and data I have presented above is just a sample of this opening but it does demonstrate the distances achieved.

Log for PY2XB from the PSK Reporter website...

Txmtr Rcvr Band Mode Distance Time (UTC)
JS6TWW PY2XB 6m FT8 19690 km 03:36:56
PY2XB JS6TWW 6m FT8 19690 km 03:36:43
JS6RTJ PY2XB 6m FT8 19376 km 02:41:56
PY2XB JR6SPH 6m FT8 19372 km 02:24:14
PY2XB JR6STV 6m FT8 19368 km 02:29:14
JD1BHA PY2XB 6m FT8 19093 km 03:43:11
PY2XB JD1BHA 6m FT8 19093 km 03:40:59
JS6TKY PY2XB 6m FT8 18947 km 02:42:59
BV3UF PY2XB 6m FT8 18768 km 03:15:26
PY2XB BV3UF 6m FT8 18768 km 02:59:44
BV7KL PY2XB 6m FT8 18721 km 03:04:56
PY2XB BV6KO 6m FT8 18662 km 03:01:44
KH6HI PY2XB 6m FT8 13059 km 01:59:26
PY2XB KH6HI 6m FT8 13059 km 01:58:14

Log for BV6KO is Taiwan
Txmtr Rcvr Band Mode Distance Time (UTC)
PT9FD BV6KO 6m FT8 19500 km 03:31:44
BV6KO PT9FD 6m FT8 19500 km 02:56:44
BV6KO PY2SRB 6m FT8 19198 km 03:30:59
BV6KO PU2WLA 6m FT8 19151 km 03:30:59
PU2MBY BV6KO 6m FT8 19151 km 03:28:44
PY5EW BV6KO 6m FT8 19142 km 03:30:44
BV6KO PY5EW 6m FT8 19142 km 03:23:29
PY5DD BV6KO 6m FT8 19129 km 03:09:14
PU5YDD BV6KO 6m FT8 19125 km 03:26:44
PY5KD BV6KO 6m FT8 18928 km 03:02:44
PY2DS BV6KO 6m FT8 18747 km 02:50:14
PY2XB BV6KO 6m FT8 18662 km 03:01:44
PY4AQA BV6KO 6m FT8 18354 km 02:45:44

DX cluster spots from stations in South America....
de dx freq obs time
PY2XB JD1BHA 50313 [LoTW] [AS-031] FT8 -17 dB 1490 Hz 0354z 12 Mar
PY2XB JD1BHA 50313 [LoTW] [AS-031] FT8 -9 dB 1492 Hz 0342z 12 Mar
PY2XB JS6TWW 50313 [LoTW] FT8 -9 dB 1727 Hz 0339z 12 Mar
PT9FD VR2CH 50313 [LoTW] FT8 -18 dB tnx 0325z 12 Mar
PT9FD BV7KL 50110 tnx qso 0324z 12 Mar
PY4AQA JS6TWW 50313 [LoTW] FT8 -16 dB 0324z 12 Mar
PY2XB JS6TWW 50313 [LoTW] FT8 -6 dB 1721 Hz 0313z 12 Mar
PY2SRB BV7KL 50313 FT8 +6 dB 774 Hz TU FB QSO 0312z 12 Mar
PY5AM JS6TWW 50313 [LoTW] <TEP> FT8 -17 dB 1750 Hz 0309z 12 Mar
PT9FD BV6KO 50313 [LoTW] FT8 -15 dB 1113 Hz 0308z 12 Mar
PY2XB BV7KL 50313 FT8 -13 dB 823 Hz 0306z 12 Mar
PT9FD BV7KL 50313 FT8 -05 dB tnx 73 0306z 12 Mar
PY2XB BV3UF 50313 [LoTW] FT8 +4 dB 1760 Hz 0245z 12 Mar
PY2XB JS6TKY 50313 [LoTW] FT8 -18 dB 1178 Hz 0243z 12 Mar
PY5AM BV3UF 50313 [LoTW] <TEP> FT8 -11 dB 1787 Hz 0239z 12 Mar
PY4AQA BV3UF 50313 [LoTW] FT8 -16 dB 0239z 12 Mar
PY2XB BV3UF 50313 [LoTW] FT8 -19 dB 1761 Hz 0235z 12 Mar
PY2XB JR6KE 50313 FT8 -19 dB 1555 Hz 0234z 12 Mar
PY2XB JR6KE 50313 FT8 -18 dB 1543 Hz 0232z 12 Mar
PY2XB BV3UF 50313 [LoTW] FT8 -15 dB 1761 Hz 0201z 12 Mar
PY2XB BV3UF 50313 [LoTW] FT8 -17 dB 1764 Hz 0136z 12 Mar