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Author Topic: FT8  (Read 218 times)

Offline NJQA

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FT8
« on: December 18, 2019, 1347 UTC »
A pet peeve of mine is when I hear someone claim FT8 operates with signals below the noise floor.  It works well, but there is no magic here.

https://tapr.org/pdf/DCC2018-KC5RUO-TheReal-FT8-JT65-JT9=SNR.pdf



Online redhat

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Re: FT8
« Reply #1 on: December 18, 2019, 1800 UTC »
That's what happens when critical thinking is no longer common practice  :o

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Offline VK3BVW

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Re: FT8
« Reply #2 on: December 20, 2019, 2112 UTC »

https://tapr.org/pdf/DCC2018-KC5RUO-TheReal-FT8-JT65-JT9=SNR.pdf
[/quote]

Thanks for this! An interesting read.

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Offline Josh

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Re: FT8
« Reply #3 on: December 20, 2019, 2205 UTC »
thread hijack!

I've yet to experience a mode where it was decoded and I couldn't still hear it clearly. I've heard from people I trust that they have had certain modes, like pactor iv, become inaudible but still print perfect copy, good psk sounds like noise anyway so a human might not be able to differentiate weak psk from noise but a machine can.

On a like note I think ROS mode, throb, or FM Hell take the first place in weak signal work on hf.

https://rosmodem.wordpress.com/
http://www.w1hkj.com/FldigiHelp-3.21/Modes/THROBdesc.htm
https://www.qsl.net/zl1bpu/HELL/PSK.htm
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Offline IZS4

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Re: FT8
« Reply #4 on: December 21, 2019, 0329 UTC »
Personally I have no interest in digital modes, But has a CW op I see the benefits of the mode and Im all for keeping ham radio alive. One of the great aspects of the hobby are all the different options to pursue whether it be HF, VHF, UHF, SSTV, CW, Satellites, FM, digital or RTTY type operation .To each their own. If you enjoy it, then do it!  (Yes im sure I left out modes of operation)
Listening on an Icom-718 with a 135' OCF dipole or a RSP2.  Grundig G3 and MLA-30 when portable. When QRP I use a Hendricks PFR-3 I built. Coverage is 20,30 and 40 meters.