Wednesday, November 15, 2017

#FT8 puzzles me?

Yes, it puzzles me? I really don't understand two things. First of all it occurs to me lately that even with 30W output I don't see a lot of "good" signal reports. At least not what I expect? And even when a station is above 0dB (that's really, really strong in FT8) they doesn't seem to see me? Take a look at the reports from 2 QSO on the picture and compare my received report with the given report from TA4SO and SV5DKL. I'm transmitting 30W not really QRP, antenna is my vertical which is always doing fine. However I give SV5DKL a incredible report of +14dB and he's giving me only -19dB? I really don't understand why the difference is so big? Is my receive that great and/or does he have so much noise and QRM?

And no, it is not consistent, I get good reports when I look on received reports at HamSpots. At that same time I worked the stations in the picture above I get a -07dB report from a station in the USA and from DX stations as far as PY (Brazil) and CX (Chili) more then 10K km away I even get reasonable reports. No, the difference in signal reports puzzles me??

Second, it looks like many stations are applying a narrow filter when they are calling. I cannot forbid that, and I really understand why when the band is crowded with signals. But many FT8 users forget that it really doesn't matter where you reply on a CQ in the waterfall. You should not necessarily reply on exact same frequency. It is even not desirable! If two or three or even more stations reply on the same frequency at the same time the CQ giving station will not decode anything. However, it seems that most FT8 users don't understand and apply a narrow filter so they only see signals in the vicinity of their own. In the newest version of WSJT-X the RX/TX is not linked anymore. However you could link them by using the shift key together with were you point the mouse in the waterfall (or clicking on a CQ). I really shouldn't tell that but anyway people seem to be consistent in replying on the same frequency you call. Well, I do understand....or actually do I. I am confused. Hopefully more and more stations will understand and will change their FT8 habits.

10 comments:

  1. My experience is similar. There's one particular station that I see routinely, coming in with a great signal. I attempt a contact every time and never get a response. "If you can hear them, they can likely hear you" isn't always the case. -K4HCK

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    1. Hello Cale, indeed propagation is not always reciproke. But most of the time it seems I receive more then the "average" station. There was only one station yesterday that gave me about the same report as I receive and that was 9K2YM which was a new one for me on 60m. On 60m I use a 2x20m inverted-V apex 12m high. 73, Bas

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  2. Living in an RFI-free, rural place, I can certainly confirm that the vast majority of people giving 'poor' reports do so because they are living alongside heavy QRM that leads to high noise, low signal (i.e. poor S/N ratio.) A lot of people don't want to accept that, though, but it's true.

    Yes, many stations calling alongside leads to anomalous signal reports. I agree about calling 'away' from the station of choice. But on 60m, this can lead to trouble, because it 'attracts' a caller away from the band limits where those apply.

    I also usually get poor reports on other modes when using a 3-ele across the Atlantic. It's sometimes propagation, but more often because the US station has a simple antenna. I can hear him, but he can hardly hear me. And, again, high RFI is a major factor in the urban US, for example.

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  3. Hello John, I know you live in a RFI free place as well and have the same issues. It looks strange when you get bad reports when you receive stations that well. But in the end it's kind of logical. These weak signal modes are excellent for people in cities with much QRM around as there is no other way for them to continue the hobby DX wise.

    I do not agree that a caller outside the band (for UK) "attracts" it outside the legal limits. As it is not forbidden to listen outside the legal frequencies as far as I know.

    73, Bas

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  4. Hi Bas,

    It's my inability to be clear, I think. On 60m two nights ago, I was on automatic 'call 1st' on FT8. Someone in Germany called me well beyond +1000Hz, which then caused my software to jump beyond the UK limit and start transmitting there - which is definitely forbidden in the UK. I stopped the transmission because I was watching it, as is required. Someone tempted to leave it running entirely autoatically might end up with a formal warning!

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    1. Hello John, one of the reasons why TX/RX cannot be locked automatically in the last version of WSJT-X. You need to press Shift to set the TX freq. to the receive freq. 73, Bas

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  5. Bas, hi. FYI, on 30m during our QSO, I was TXing at 45W output and a WARC bands fan dipole. I usually have no noise on 30m, my area is relatively RFI- & environmental noise-free, although rural. Unfortunately, I wasn't at the shack, at the time of our QSO, to assess your signal strength, in audio terms. I have been using a fully automated FT8 Robot since 24th July, which is running completely unattented, sometimes 24/7 when I'm off to a business trip and the like. It only takes a mouse click to import logged QSOs to Logger32 and upload to LoTW, eQSL.cc & Clublog. It has worked approx. 10100 QSOs for me so far, until this morning. Hope for more QSOs with your station in the future, maybe other bands, too. 73 de Stathis, SV5DKL

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    1. Hello Efstathios, I was using our QSO just as a example. I have this with many stations. Not shure what caused the big difference in signal strength??

      A FT8 robot....now you make me curious? Will send you a e-mail this evening.

      73, Bas

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    2. Tutorial video on how to set up a FT8 full automatic and unattended Robot like mine is online at youtube.com

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    3. Thanks, this will be interesting! 73, Bas

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Thanks for your comment. Bedankt voor je reactie. 73, Bas