Introduction... QRSS is a beacon mode where callsigns are sent at very slow speeds in morse code and it's a useful mode for investigating radio propagation. The signal can usually be found on the main HF bands just below the WSPR signals.
For example, the 10m WSPR frequency is 28.1246 MHz USB and the WSPR signals are in the audio range of 1400 to 1600 Hz. Using the same dial frequency, the QRSS signals are about 400 Hz lower in frequency around 1100 Hz.
This has the advantage of using programmes like WSJT-X to decode the WSPR signals while at the same time, you can see the QRSS signals with programmes like SpectrumLab which displays the audio spectrum.
Some people operate 'grabbers' which take screen grabs of the QRSS band from their receiver and these are them put up on a website. They usually update every 10 minutes.
28 MHz tests... At about 12:00 UTC on the 29th of May 2024, I noticed that there was a Sporadic-E opening between Sweden and Ireland. The image above shows how my callsign was successfully received by the SA6BSS grabber in Sweden at a distance of about 1554kms.
How to send QRSS signals... If you are already using FT8 with programmes like WSJT-X then you are all set up for sending QRSS signals. For my tests, I was just using my HF radio and a PC.
The first thing I did was to go to the PA2OHH website and using the SPACE, DOT & DASH tabs, I generated my callsign in morse code. The audio can be adjusted from 1500 to 1900 Hz. The QRSS mode can be adjusted for length as well as whether it is on/off or uses Frequency Shift Keying (FSK).
After pressing 'Start QRSS', it's just a case of waiting for the sequence to start which happens at 10-minute intervals past the hour e.g. 12:00, 12:10, 12:20 and so on. In my case, it was really as simple as holding the microphone next to the PC speaker and pressing the PTT once the QRSS sequence started.
In terms of frequencies, I used the default 1600 Hz option. I tuned the radio down about 300 Hz from the WSPR frequency to about 28.1243 MHz USB. This made sure that my transmit signal was below the WSPR band and above the other QRSS signals.
If we look at my signal above in more detail, the bright part at the start was when the audio from the PC speaker was too loud and I had to turn it down. The rest of the QRSS audio resulted in an output power of about 5-10 watts from my radio.
There is also a very obvious upward drift in the signal! My callsign was sent over the space of just over 5-minutes and in that time, my signal drifted upwards by about 10 Hz.
My HF radio is quite old and for modes like CW or SSB, 10 Hz is really nothing. If you were to listen to CW or SSB signals from my HF rig then you'd hear nothing wrong. It's just that with QRSS, tiny changes like 10Hz become very obvious.
Nearly all QRSS signals on the bands are from dedicated transmit modules which are GPS stabilised. You can see these is the top image as nice straight signals. In my case, there is probably some crystal oscillator in the transmit chain in my HF radio that is being turned on and is drifting slowly as it warms up.
Aurora... Back on the 10th of May 2024, I tried this QRSS test as well during the big aurora.
Using the same grabber in Sweden, the signals from the SE of England are there and are of course distorted by the aurora. I'm almost certain the signal above is me and it even has that little telltale upward drift.
In hindsight, I probably should have used on/off keying rather than frequency shift keying and the signal would have been a lot more obvious. It's still pretty cool to see your own signal coming back from the auroral region.
In conclusion... What I have outlined above is basically just putting the microphone from your radio up to the speaker of a PC and checking a website to see if your signal was heard, it's really that simple. It would be nice to see others giving it a try.
Links... Here are some useful sources...
1) https://groups.io/g/qrssknights - This email group is the place to go for all things QRSS related.
2) https://www.qsl.net/pa2ohh/21htmlqrss01.htm - PA2OHH website for generating QRSS signals.
3) https://www.qsl.net/sa6bss/ - SA6BSS grabber in Sweden.
4) https://www.qsl.net/pa2ohh/grabber.htm - PA2OHH grabber in the SE of Spain.
5) https://qsl.net/g4iog/ - G4IOG grabber in SE England
6) https://www.qsl.net/g0ftd/grabber.htm - G0FTD operates a grabber from various online receivers.
7) https://qsl.net/wa5djj/ - WA5DJJ operates several grabbers from New Mexico in the United States.
8) https://swharden.com/qrss/plus/ - AJ4VD has links to a lot of grabbers
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