VO1FN : The 144 MHz Trans-Atlantic SDR Monitoring Station - Update 2021

 

Frank, VO1HP reports that the VO1FN 144 MHz Trans-Atlantic monitoring station will be reactivated by the end of May 2021!

This SDR receiver will be using SDR Console V3 and WSJT-x and will report to the PSK Reporter website as VO1FN.

The station will be located in St.John's, Newfoundland and will use two stacked 5-element 144 MHz LFA-Q quad style Yagis from Innovantennas.

The antennas will be pointing at western Europe and the receiver will be listening on 144.174 MHz which is the FT8 frequency.

Trans-Atlantic on 144 MHz: Is it possible??? ...As can be seen from the map above, the distance across the North Atlantic between Newfoundland and Ireland is just over 3000kms. This is well beyond the normal 2300km or so range for normal Sporadic-E or meteor scatter and it seems unlikely that it would be spanned a marine tropo duct going all of the ways across.

I emphasize the work unlikely but it's not impossible. The North Atlantic is not noted for its fine calm weather and there is nearly always some low pressure system in there stirring things up.

What is likely to happen a lot more often are shorter ducts that are in the region of 1000kms in length and these could happen at either end although the eastern end seems more likely. If there is a Sporadic-E opening or a major meteor shower at the same time as a good 1000km marine duct then it may well be possible.

It seems to me that the path from Newfoundland to the north-west coast of Spain as the most likely one even if it is a bit further away. The number of stable marine ducts in that part of the Atlantic are higher than further north closer to Ireland.

Updates... More news as it comes in!

Links...

1) VO1FN page on QRZ

2) F5LEN's tropo forecast

VHF Tropo forecast for the North Atlantic path - Weekend 3rd & 4th April 2021

 

According to the tropo forecast website of F5LEN, there is a chance of enhanced tropo conditions across the North Atlantic on the weekend of Saturday 3rd & Sunday 4th of April 2021.

While contacts at 144 MHz are probably unlikely, any suitably equipped stations in Ireland, the UK, France, Spain & Portugal might be interested in trying.

Frank, VO1HP reports that the following stations will be monitoring from Newfoundland mainly on the FT8 frequency of 144.174 MHz...

VO1IV Aaron - St.Johns Newfoundland - (10el yagi, FT991, 50w) - 144.174 MHz FT8

VO1DZA Graham - St.Johns Newfoundland

VO1WEB Matt - St.Johns Newfoundland

The distance across the North Atlantic is in excess of 3000kms and has yet to be bridged on 144 MHz.

* * *

Frank also reports that they plan to get their SDR Transatlantic Beacon Receiver site operational in May of 2021 when the antennas are taken out of storage.

Links...

1) F5LEN tropo prediction website

Long distance Sporadic-E on 144 MHz...

This is something I meant to post a while back but never got around to it unil now.

Back on the 3rd of July, there was some excellent Sporadic-E propogation over Europe with some very impressive distances. One of those contacts was between Tom, EI4DQ (IO51wu) and SV9CVY (KM25ka) on the island of Crete, a distance of about 3,213 kms. Anyone that knows about Sporadic-E will know that the usual maximum distance for 1 hop is around 2,300 kms so the above distance is unusual. (On the map above, 2300 kms would be roughly from EI4DQ to roughly the heel of Italy).

Now, there are probably 3 possible explanations for this type of contact...

1) Double hop Sporadic-E as shown above...using clouds #2 and #3

2) Chordal hop where the Sporadic-E clouds may be slightly tilted and the signal goes from cloud to cloud rather than bouncing off the ground in the middle.......i.e. the signal goes directly from cloud #2 to cloud #3.

3) There was an extension at either end or both ends due to tropospheric propogation.

Considering that the MUF does not reach as high as 144 MHz that often, it's remarkable that it should happen in 2 spots at once. Hence, that's why these type of contacts are pretty rare.

Now for a bit of fun ;o)......what happens if we take that 3,213 km contact and plot it from EI4DQ's location in the opposite direction...

In fact, if EI4DQ managed to get a signal to travel that far to the west, it would end up in Newfoundland! To date, no-one has managed to make a contact accross the Atlantic on 144 MHz and it remains the 'holy grail' of VHF propogation. In fact, the IRTS have a special trophy called the Brendan Trophies for the first 2 stations to achieve this special contact.

Now, there's a big difference between the path from EI to SV9 compared to the path from EI to VO (Newfoundland). For one thing, EI to VO is a lot further North and Newfoundland is a lot closer to the magnetic North pole, all factors which seem to reduce the chances of there being suitable Sporadic-E.

It does however raise the question of whether it is possible? Europe to North America direct on 144 MHz.......can it be done???