New to FT8, I have a question due to not as much success as I hoped.

Discussion in 'Working Different Modes' started by VE3GZB, Jul 3, 2018.

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  1. VE3GZB

    VE3GZB Ham Member QRZ Page

    For my birthday I got myself a new little radio (IC-7300) which lets me connect to a computer (in this case I'm using a small single board computer, the Odroid XU4 running Ubuntu MATE). And programs such as WSJT and FLDIGI seem to behave without stressing the computer.

    I was using a Windows 10 box but I like the power savings these little single board computers have to offer and they seem to lack little in performance.

    Yes I have time synchronization on the Odroid and it seems to keep precise time, and I have adjusted the digital drive levels so the ALC isn't being tripped.

    I'm not succeeding as much as I thought I would have using FT8. Yes I have had a few contacts on FT8 using both Windows and the Odroid, and I love chasing DX, and I can see the callsigns of the DX station in the table on the left and the successful replies by others on the right.

    One thing which confuses me a little is this TX even choice. I can select or deselect it. I suspect I'm not using it correctly which explains why I'm not getting more contacts.

    I read the user guide and it's not clear on this point. The manual seems to go on ponderously for a thousand different things but doesn't really clarify when that little function should be use and how to determine when and when not to use it. Does the program decide this on it's own or does the user have to input something, and if so then when?

    Thanks and 73s,
    VE3GZB
     
  2. K5URU

    K5URU Ham Member QRZ Page

    Think of it this way. If the "Tx even/1st" box is checked, and you decide to call CQ, the program will wait until you reach either the beginning (xx:00) or midpoint (xx:30) of the minute. You could think of this as Evens. If the box is unchecked, you could think of it as Odds, meaning xx:15 or xx:45. Anyone replying to your CQ would want to reply on the opposite setting, so you can hear each other.

    On the other hand, if you wanted to respond to someone else's CQ call, you would double-click it when it appears in the decoding window. Doing so will set your Rx frequency to line up with the caller, and the program will automatically either check or uncheck the TX Even box, as appropriate, so that your radio transmits opposite of their radio.

    As far as feeling like you're not getting the most out of FT8: The link below will take you to a short guide (separate from the online user manual) that contains a lot of useful tips that make a big difference. I really wish they would put a link to it right after the manual on the WSJT-X page, because it would help a lot of beginners as well as many experienced users get a lot more out of WSJT-X. After reading it once, you might not understand all of it, but you'll be off to a good start, and some of the other points will make more sense once you've experienced those situations. One of the most important tips in the guide is to check the box that says Hold Tx Freq. That one tip alone can dramatically improve the success rate of anyone who didn't have it checked before.

    https://www.physics.princeton.edu/pulsar/K1JT/FT8_Operating_Tips.pdf

    Give that a shot and if you come across any more questions, definitely ask! I'm happy to help if I can.
     
    JJ0UYX, AB8MA and VE3GZB like this.
  3. VE3GZB

    VE3GZB Ham Member QRZ Page

    Thank you. This is precisely what I wanted to understand! Chasing DX across the pond is what I love ham radio for, so I rarely wish to call CQ on my own. It's in the responding to the CQ DX of others where I was struggling with the proper coordination and use of the WSJT software. Your reply helped me greatly!

    It is a ponderous manual. Imagine following a recipe this large for a meal or a cake and all you want to look up is how much salt to add.

    73s, VE3GZB
     
    K5URU likes this.
  4. W7UUU

    W7UUU Super Moderator Lifetime Member 133 Administrator Volunteer Moderator Platinum Subscriber Life Member QRZ Page

    Important: Be sure to click "hold TX frequency" and use "Split" - find an empty (dark) space in the waterfall somewhere, and hold down "shift" then "left click" somewhere in that dark space. The little red "goal post" should then be aligned over the dark space (i.e., no signals visible so you're not QRM'ing another station)

    The software couldn't care less where in the spectrum you transmit. As long as "hold TX frequency" is checked, and the spot where the red bar is remains unused by others, you'll be happily in "split mode" and the software will simply work things out.

    If you don't do the above, and just work "simplex" - the red bar and the green bar will both line up - and if you then call a station calling CQ, you'll be transmitting right on their frequency which means if you're the strongest station, the other guy "must" work you as his software will lock on!! He may very well NOT want to work you but rather others behind you with lower signal levels.

    I learned this the hard way - I got a few emails calling me a "Lid" but no one explained it until a local ham at the club that I worked last month told me "don't do that! it's rude!" and proceeded to explain the correct procedure.

    Hope that helps,

    Dave
    W7UUU
     
    W7TCT, K2CQW, W2VW and 1 other person like this.
  5. VE3GZB

    VE3GZB Ham Member QRZ Page

    Thank you! 73s VE3GZB
     
  6. VE3GZB

    VE3GZB Ham Member QRZ Page

    I noticed if I check off the "split operation" function in the preferences (F2) and choose "Rig", then upon transmission the radio functions on a slightly different frequency. Is this a desirable thing to have happen?
     
  7. K5URU

    K5URU Ham Member QRZ Page

    Hi Dave,
    The problem isn't really that they'll be forced to work you - they could uncheck the "Call 1st" checkbox if they want to choose who to answer instead of automatically answering the first decoded caller. The issue is that any CQ, especially from a desirable station, can result in a mini-pileup, and because of the nature of the mode, it only takes a few equally strong signals responding on the same frequency to jam each other, so nobody gets through. A simplex pileup in FT8 is even more problematic than other modes, because everybody starts and stops responding at the exact same time, and there is no such thing as a partial decode in FT8. The computer can't ask "Who was the UUU?"

    Regardless of that, you were certainly not a lid for operating that way. Unfortunately, going all the way back to JT65 and JT9, simplex operation was the default method and it just carried right over into FT8. It's strange that there doesn't seem to have been much effort to publicize that working split is considered to be the new best practice. The advice is presented prominently in the Operating Guide, but the Operating Guide itself is sort of hidden behind a URL, with no prominently published links to it. Then again, this is an experimental mode with free open-source experimental software, so it's hard to complain.
     
  8. KP4SX

    KP4SX Premium Subscriber QRZ Page

    Not really. I have carefully monitored this to figure out who gets called first. I see no rhyme or reason based on signal strength, DT offset, freq offset, who hit the key first, etc. The algorithm is apparently more complicated than it would seem at first blush.
    As far as holding a transmit frequency...that may work on a less than busy band and I do it often...on 6m. When things are really tight you'll get covered up within minutes and then YOU become the QRMer for not being agile and moving.
     
    W7UUU likes this.
  9. W7UUU

    W7UUU Super Moderator Lifetime Member 133 Administrator Volunteer Moderator Platinum Subscriber Life Member QRZ Page

    True - I do end up moving around quite a bit but many times I can stay "parked" for some time, always minding the waterfall for someone calling.

    Interesting about the "no rhyme or reason" - I just figured it was "strongest signal wins".

    Either way, I learned never to run FT8 unless in split mode and life's been good ever since :)

    Dave
    W7UUU
     
    K2CQW likes this.
  10. W4NNF

    W4NNF XML Subscriber QRZ Page

    Part of the problem is just conditions. Otherwise? You don't want to melt down your finals, but keep your power at about 40 - 50 watts. One mistake people make is reducing the transmitter's RF power. Don't do that. Leave it set at 100 watts (or whatever). Adjust power by adjusting the ALC level (like on your interface or, with the 7300, with "USB Level"). Set that until output power is 40 watts or so. That results in a cleaner, easier to decode signal. The ALC indication on the transmitter should be 1 - 2 bars at most.
     
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