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Using FT8 to demonstrate Antenna Orientations

Discussion in 'Amateur Radio News' started by KM9G, Oct 6, 2021.

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  1. KF0DHQ

    KF0DHQ Ham Member QRZ Page

    I know this is probably not the greatest question to ask on this forum because its about antenna angles or something but WHY THE HECK IS FT8 SO IMPORTANT? As far as I know (Which is not to much) FT8 is another digital mode that uses packets I think. So can someone tell me why its so important or why it's better than any other digital modes?
     
    M1WML likes this.
  2. W1YW

    W1YW Ham Member QRZ Page

    FT8 is a version of earlier digital modes invented by Joe Taylor, K1JT, and then enhanced in collaboration with others. By using a sync-clock at a fixed sub band , the mode allows a matched filter that has a lower detection threshold than many other digital modes, and certainly far lower than legacy analog modes, while also allowing a small QSO exchange. This is done in a fairly short period of time.

    The release of this free digital mode coincided with the bottom of the sunspot cycle, with pea-poor propagation on the HF bands. People quickly discovered that low power, even with really poor propagation and modest antennas , allowed transcontinental contacts on otherwise dead HF(for example) bands, when using FT8.

    FT8 just requires a rig and a clock/laptop. These are things already in peoples' shacks.

    Essentiallly it was the right 'product', at the right time, at the right price. At this point the 'install' base is a large fraction of the worldwide ham population.

    IOW FT8 wins because it is 'good enough', free, easy, and universal.

    73
    Chip W1YW
     
    KF0DHQ, M1WML, W0PV and 1 other person like this.
  3. KF0DHQ

    KF0DHQ Ham Member QRZ Page

    Okay. I don't really dabble in digital modes that much but I've herd so much about FT8 I just wanted to see what all the fuss was about. Thanks for Explaining!

    73's KF0DHQ Jack A. Weigel
     
    M1WML likes this.
  4. W1YW

    W1YW Ham Member QRZ Page

    I suspect others may have additional thoughts. Jack. I am not a big user of FT8 or other digital modes. My perspective is coming from looking at FT8 as a disruptive innovation, and telecom mode, topics of personal interest to me.

    I like to be more physically engaged in my contacts. That is a bit old school, but works for me. Others have different opinions.

    73
    Chip W1YW
     
    Last edited: Oct 11, 2021
    M1WML and KF0DHQ like this.
  5. KF0DHQ

    KF0DHQ Ham Member QRZ Page

    I'm pretty new into the hobby ,going on the sixth month I believe, but I never been a fan of the digital modes and internet modes. I like the old school style, it's the only thing I understand.;)

    KF0DHQ Jack A. Weigel
     
    PY2NEA, M1WML and W1YW like this.
  6. KO4CES

    KO4CES Ham Member QRZ Page

    FT8 utilizes a 7.5 second transmit time and 15 seconds to receive. According to Joe Taylor, he actually intended FT4 to be the prevailing mode. You’ll probably glean a lot of information directly from the Princeton University’s website.

    My opinion, FT8 simply predominanted by way of group dynamics. I chose FT8 because that’s what the majority use at present.
     
    KF0DHQ, M1WML, KK2DOG and 1 other person like this.
  7. KK2DOG

    KK2DOG XML Subscriber QRZ Page

    People often make the mistake of calling it a low-power mode when it's actually considered a weak-signal mode.
    VHF/UHF SSB is also considered a weak-signal mode but there are plenty of folks who operate QRO there too.
     
    K0UO, KM1H, KC7ZXY and 3 others like this.
  8. W3ATT

    W3ATT Ham Member QRZ Page

    Yes it is a weak signal mode, and when I run FT-8, it's 400 watts minimum. And I get an answer every time. I mentioned this before in a forum and people got mad at me because they said I would drown out other stations, but doesn't their 50w drown out guys who are trying QRP? LOL.
     
  9. KE0GXN

    KE0GXN XML Subscriber QRZ Page

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    W1YW likes this.
  10. N6SPP

    N6SPP XML Subscriber QRZ Page

    Precisely. !Bravo! As elmers, we've got to help the newer hams understand why super narrow JT modes like Fst4, Fst4w, JT9-x,y,z, wspr, and FT8 work so well. These modes work well with low rf power and inefficient antennas. The increase in attention to using an "End fed wire and FT8" combo in the last three years or so, is a prime example. A loaded fishing lure and ft8 will net dx. Loading up a window screen and running a counterpoise off the coax shield along the carpet, while running FT8 or WSPR, will yield dx or dx spots.
     
  11. W1YW

    W1YW Ham Member QRZ Page

    OK,

    Here is why you shouldn't do that---

    When you use a (call it unconventional) end-load, you are almost certainly producing RF from the coax. Now, even though the power may be low, say less than 100 watts, the RF is now coming in no small part from the coax, and may be maximum at the xcvr connection point. That means you, the operator, and others, are in the extreme near field of the antenna and likely exceeding the RF exposure requirements, and may be even exposing people who arent even aware you are transmitting.

    IOW you may be operating illegally.

    Again, just because you can, doesn't mean that you should. If you want to be punk-clever on radiating a paper clip or a shopping cart (for example), then know beforehand what is actually radiating (i.e. more than the paper clip) and the prudence required in using same in Part 97.

    I know some here will be extremely angry AT ME for stating this. That is not what I desire nor deserve and is a cruel and false shaming (seen here as several post by several hams) of a fellow ham, for no reason other than an attempt to ostracise.

    Don't shoot the messenger.

    Again the real message must hit home: Use best practices and use legal practicing of the radio art.

    Knowledge and 'best practices' are readily available from many of your ham colleagues. Cancel-culturing any of them is cruel, unjustified, and puts the entire community at risk (by shunning that base of knowledge and best practices).

    73
    Chip W1YW
     
    Last edited: Oct 17, 2021
    N6SPP likes this.
  12. K9RDU

    K9RDU Ham Member QRZ Page

    I have been doing exactly this for about 2 months and 2000 qsos, but to test my inverted zs6bkw that is only 25 feet off the ground at the center, with the ends at right angles resting on the horizontal fence railing.
    There are a lot of good and valid points in here about general testing, atmospheric conditions, etc. but all I (and I imagine most people) care about is "what is my antenna capable of ON AVERAGE", "What is the BEST in has done?", and "What headings and I most effective and where am I deaf?". Gridtracker will show you a lot visually, dxkeeper ant_az <compute> advanced filter (combined with date if you are manually rotating a fixed antenna) gives you a lot of raw data. You can generate a report, import into Excel and graph to your heart's content (the scattergram radar graphs are particularly useful).
    I now know things like effective distances (with the bouncing, it's interesting. I can't touch the Midwest, but you want Hawaii, or even Australia, no problem. I can cover all of EU, but Asia eludes me) and direction I'm most effective in within 5 degrees BEFORE my handicapped butt goes wheeling through the mud to move wires.
    I can tell you this: The reality of what my antenna does is COMPLETELY different than what any model shows...and therein lies the value.
     
    W1YW likes this.
  13. K9RDU

    K9RDU Ham Member QRZ Page

    I wish more people WOULD get on board with FT4, it's like FT8 in half the time. FT8 is roughly akin to watching paint dry (but I keep it running all the time because I'm always on the computer and there's basically nobody on FT4).
    I think it suffers because of the naming. To someone unfamiliar (including me a few months ago), it's presumed that FT8 came after FT4 (higher number) and therefore is newer and better. Call it FT8.2 or FT16 and they will come.
     
    KC7ZXY and KO4CES like this.
  14. M0TTQ

    M0TTQ Premium Subscriber QRZ Page

    Once I started doing a bit of FT4, FT8 seemed unbearably slow.
     
    KC7ZXY likes this.
  15. W0PV

    W0PV Ham Member QRZ Page

    As suggested by Chip W1YW, for those that would like to use their integrated radio-PC (ie, an FT8 station) and contribute to a REAL SCIENCE PROJECT check out this link to a QRZ General Announcement post regarding the upcoming "Frequency Measuring Festival" of WWV Doppler shift, an event run by EE grad student Kristina KD8OXT being held during the upcoming Antarctic eclipse.

    Other direct links,

    Main Web Page

    December 2021 Eclipse Festival of Frequency Measurement

    How to Collect Doppler Data With Your HF Radio

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    Last edited: Oct 20, 2021

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