FT4 splatter and FT8 and FT4 ops

Discussion in 'Working Different Modes' started by KB2E, Aug 29, 2019.

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  1. KB2E

    KB2E XML Subscriber QRZ Page

    My FT4 experience has been one similar to FT8 but with a twist. It appears that there's some big power being run. Perhaps the 5 seconds tansmit gives people some ease about using their amp. Please, you don't need that kind of power. I'm sending sometimes +23 to 28 reports! Many signals are SOLID red and very wide. I see this on FT8 somtimes but not often. To each his own but WOW, what signals I see on FT4.

    Next, and a rant of sorts, if you're one who thinks auto-sequencing isn't a real contact that's OK, I have no problem with it, run it manually if it makes you feel better. But for God's sake man PAY ATTENTION!! There's no way I'm going to believe that someone sent me a +05 and then 13 (or 5) seonds later can't hear me anymore and doesn't hear me again until I send a dozen or more R whatever. Why? Because after the 12th or maybe 20th R whatever I get a +05 or higher, AGAIN!! Either learn to run the software, pay attention, or let it auto-sequence!

    I just worked a station before I wrote this who sent me a +06 to which I replied with a R+01. He proceeded to send the +06, a +04, a +06 and a +01 and he can't hear me send his R+01? It's mind boggling how a simple piece of software and a 5 step manual or automatic process is so difficult for people to understand and run.

    My head to toe firesuit has been donned
     
    K4AGO likes this.
  2. ND6M

    ND6M Ham Member QRZ Page

    Isn't FT 4 designed for contests?
    You can't be a contestor unless you are (at least) QRO....:rolleyes:
     
  3. KA9JLM

    KA9JLM Ham Member QRZ Page

    Just like any mode, Spin the dial or find something better to do, Like working on a electronic project.

    Crackers go good with W
    (h)ine. :)
     
    WB9QVY likes this.
  4. W4RAV

    W4RAV Ham Member QRZ Page

    I figure the cause of most "splatter" complaints are more often the receiver than the sender.

    loweryourgain.JPG
     
    KK5JY likes this.
  5. MM0IMC

    MM0IMC Ham Member QRZ Page

    These may help with splatter too!;):p

    download.jpg download (1).jpg
     
  6. K4AGO

    K4AGO Ham Member QRZ Page

    One of the laws of physics is that the more power you use, the more bandwidth you occupy.

    It's NOT the receiver. It is the low power mode (FT8 FT4 etc.) stations running 1500 watts.

    Not only that, they get angry when you mention that FT8/FT4 is a low power /weak signal mode.
    John
     
    AG5DB and KZ4KX like this.
  7. K4AGO

    K4AGO Ham Member QRZ Page

    These modes (FT8, FT4, etc.) were designed by Dr. Joe Taylor and team to be LOW POWER and WEAK SIGNAL modes. There are hams out there that run these modes at 1500 watts. The more power you run, the more bandwidth your signal uses. It's a law of physics. These same hams will rudely argue that weak signal does not mean low power. Dr. Joe Taylor and team did not design the JT modes to be high power modes. Anything above 25 watts is an obscene amount of power.

    Some will even wrongly try to convince you that the problem is your receiver. And, then, they will accuse you of whining.

    The instruction manual that comes with the WSJT x modes states that using these modes, world wide communications is possible using milliwatts of power and a compromise antenna. Nowhere in the manual does it say that these are high power Kilowatt modes.

    Also, § 97.313 Transmitter power standards state that "an amateur station must use the minimum transmitter power necessary to communicate."
    Some hams have convinced themselves that they cannot communicate using less than 1500 watts. They will also falsely state that the amount of power they use is left up to their discretion. § 97.313 clearly states otherwise.

    I never run more than 25 watts on the WSJT X modes. Most of my contacts (more than 4000 the first two months using FT8) were made at less than 10 watts. My transceiver won't go any lower than 10 watts. If it did, I would use less than 10 watts.

    The FT8 / FT4 band segments are a mess because these power hungry hams take up extreme bandwidth by running obscene amounts of power.

    You can kill squirrels with an atom bomb. But, is that really sporting? Absolutely not. The collateral damage is too great just as it is in using high power on FT4 and FT8. You can look at the waterfall and pick out the stations running too much power. They are the ones taking up enough bandwidth for three low power stations to operate in.

    I have stopped operating WSJT X modes for these very reasons.
    John
     
    KC9YGN likes this.
  8. W4RAV

    W4RAV Ham Member QRZ Page

    Unless the person receiving has asked, and got an honest answer, he has no idea how much power a person is running.

    Although when I get a strong report, my power is lowered before I transmit again. (Say I get +10 with 25W, my next TX would be QRP.)


    You can run a 1500W FT8 signal and it'll be flawless, assuming you do so correctly.


    I don't have that experience. But I also rarely see splatter, although I've monitored 1000s of hours.
     
    KT5WB likes this.
  9. K8AC

    K8AC XML Subscriber QRZ Page

    KB2E - perhaps a Valium would be better than a fire suit. There's so much misinformation here that it's hard to know where to start. To begin with, I will agree that FT8 is a weak signal mode. Whether or not it's a viable low power mode depends entirely on the band and propagation conditions, the geographical/topological conditions at each end of the path, how far apart the two stations in QSO are and a few lesser factors. For example, if I'm chasing deep Asian DX in the morning on 20 meters, it can easily take 1,200 watts to a gain antenna to be heard in Asia. It may be that while the DX station is copying me at -22 that I'm +10 or +20 somewhere in the northern USA. That's just the way things are.

    Second, I suggest it is total poppycock to say that "it's a law of physics that the more power you run the more bandwidth the signal takes up". It that were true, it would be a simple matter to cite a source for information on that "law" and I challenge all supporters of that idea to come forth with that. Is it possible that some stations when running high power will exhibit a greater bandwidth? YES! But it's not because of a "law of physics" it's because the operator doesn't have a clue about how to adjust the audio drive to avoid the resulting distortion products. With these digital modes, increasing power DOES NOT have to increase bandwidth. But, if you overdrive the exciter with the audio source, the signal will indeed be wider and that is true whether the mode is SSB, AFSK, FT8, FT4, etc.

    I could cite you a half dozen reasons why the station you called with strong signal reports both ways isn't copying you for a long period of time. For one thing, he could be suddenly experiencing a high noise level that is intermittent. Or, more likely, a stronger signal has come on either his frequency or yours. The fact that you don't see it on your display doesn't mean it isn't there. When I run into this situation, I immediately shift my frequency to an apparent open spot on the band and continue calling. Most of the time, that solves the problem immediately.

    Regarding geographical/topological conditions: I'm located down in a bowl in the mountains, surrounded on three sides by close-by peaks rising more than a thousand feed above my antenna site. Through careful experimentation, I determined that working DX in those directions means running 800 watts or more output. Even so, my report from the other end is usually around -15 or so for DX stations. US stations along the path of course will see a much stronger signal. If I ran 20 watts as many suggest, I'd be lucky to reach more than a couple hundred miles.

    Another factor: Many of the guys running low power or QRP are using low-end receivers and don't know how to use AGC on them. Don't forget that you're listening to a 3 KHz or so bandwidth that may contain many dozens of signals, many of which are strong. These receivers are easily de-sensitized by strong signals as they drive the AGC. Sometimes even with a high-end receiver it's useful to turn off the AGC and ride the RF gain manually to reduce the effects of the strong signal(s). And here's something folks rarely think of: you're not limited to using a 3 kHz bandwidth for receive. If bothered by strong signals, it's a simple matter to crank the receiver selectivity down to a CW-like bandwidth of, say, 500 Hz, and then use the passband tuning on the receiver to move the now narrow passband aross the 3 kHz spectrum. Weak signals that may have been previously blocked by strong ones will suddenly pop out of the noise and be perfect copy.

    These are weak signal modes and under the right conditions can be low power modes as well. But, there's no reason at all that low power stations can't coexist with high power stations. That's been working out just fine for other modes for many decades and it works for FT8 and FT4 as well.

    73, Floyd - K8AC
     
    WG7X, W2VW, K4RKY and 3 others like this.
  10. W4RAV

    W4RAV Ham Member QRZ Page

    What an excellent well thought-out post Floyd.

    I'm so keeping the link to it to reference your reply. I'm sure there will 1000 more threads started by people who don't know how (or care to) understand.
    (It's a lot easier to complain than it is to problem-solve.)

    73


    PS As an after-thought, I wonder if Ed (the OP) is keeping to the format of automated contacts? Is the other guy repeating (with different reports) because the software doesn't recognize, say just "TY RR73" vs "call call RR73"? I don't use the auto-QSO (but have no issue if others do), so I don't know if that's a valid consideration.
     
    Last edited: Sep 9, 2019

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