Trans-Atlantic opening on 28 MHz - Sun 7th June 2020

There was a nice trans-Atlantic opening on 28 MHz and 50 MHz late on Sunday the 7th of June 2020. I had no real interest in trying to make any contacts so I left the radio monitoring the WSPR frequency on 28.1246 MHz.

WSPR signals heard...

Timestamp Call MHz SNR Drift Grid Pwr Reporter RGrid km
 2020-06-07 23:40 W8AC 28.126032  -24  0 EN91jm  5  EI7GL IO51tu  5434
 2020-06-07 23:28 W8AC 28.126032  -26  0  EN91jm  5  EI7GL IO51tu  5434
 2020-06-07 23:24 W8EDU  28.126102  -26  0  EN91fm  5  EI7GL IO51tu  5455
 2020-06-07 23:12 W8EDU  28.126102  -23  0  EN91fm  5  EI7GL IO51tu  5455
 2020-06-07 23:10 W8AC 28.126032  -25  0  EN91jm  5  EI7GL IO51tu  5434
 2020-06-07 23:04 W8EDU  28.126102  -26  0  EN91fm  5  EI7GL IO51tu  5455
 2020-06-07 22:58 WA9WTK  28.126062 -23  0  FN42fk  10  EI7GL  IO51tu  4734
 2020-06-07 22:58 WB8ILI  28.126083 -25  -1 EN82pq  5 EI7GL IO51tu  5451
 2020-06-07 22:56 W8EDU  28.126102  -22  0  EN91fm  5  EI7GL IO51tu  5455
 2020-06-07 22:18 WA3DNM  28.126074 -18  0  FM29fw  5  EI7GL  IO51tu  5168
 2020-06-07 22:10 VE1VDM  28.126125 -26  0  FN85ij  2 EI7GL IO51tu  4001
 2020-06-07 22:00 VE1VDM  28.126125 -23  0  FN85ij  2 EI7GL IO51tu  4001
 2020-06-07 21:58 WA9WTK  28.126063 -22  0  FN42fk  10  EI7GL  IO51tu  4734
 2020-06-07 21:50 VE1VDM  28.126125 -21  -1 FN85ij  2 EI7GL IO51tu  4001
 2020-06-07 21:40 WA3DNM  28.126075 -17  0  FM29fw  5  EI7GL  IO51tu  5168
 2020-06-07 21:40 VE1VDM  28.126124 -23  0  FN85ij  2 EI7GL IO51tu  4001
 2020-06-07 21:38 WA3DNM  28.126075 -15  0  FM29fw  5  EI7GL  IO51tu  5168
 2020-06-07 21:30 VE1VDM  28.126124 -22  -1 FN85ij  2 EI7GL IO51tu  4001

VE1VDM was the first signal heard at 21:30 UTC and the last trans-Atlantic signal was from W8AC in Ohio at 23:40 UTC.

Most of the stations were running 4, 5 or 10 watts. The strongest SNR (Signal to Noise ratio) was -15dB which would have meant that it was buried in the noise and barely perceptible by ear.

I suspect the signals from VE1VDM may have been double hop Sporadic-E while the US stations were triple hop.

QRSS... Most the QRSS (very slow morse) transmissions from North America are just below the WSPR frequency. This allow you to look at the WSPR waterfall display in WSJT-X and see if there are any QRSS signals there.

As soon as I heard VE1VDM in Nova Scotia on WSPR, I opened up the SpectrumLab programme to take this screen grab...

In the graphic above, the vertical dotted lines mark 5 minutes of time so the scan from left to right took about 20 minutes. You wouldn't want to be in a rush to go anywhere with QRSS 😊

The signal from VE1VDM was actually stronger before this grab was taken so I would guess the QRSS signal is equivalent to roughly a -22dB WSPR signal. This seems to be about the limit of where a QRSS signal can be seen properly.

The really interesting signal though is the 100 milliawatt one. If you know the QRSS callsign in advance, you can infer the relevant information from the fragments on the screen even when the signal is much lower.

As an aside, I did see a very weak sawtooth waveform as ell during the opening.

I'm assuming for now that it was just some sort of local interference but I took a screenshot of it just for reference.

Low Band VHF... After seeing a report on Twitter about US fire traffic on 33 MHz, I had a quick look and I did come across a weak unidentified signal on 33.900 MHz. I think I was too late though and the band was closing at that stage.