JS8CALL (FT8CALL on Steroids) 20wpm - 24 db / Jordan KN4CRD does it again!

Discussion in 'Amateur Radio News' started by NN2X, Oct 7, 2018.

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  1. WG7X

    WG7X Premium Subscriber QRZ Page

    So much thread drift; so few pages!

    It's a modern miracle!
     
    KF4ZKU, KV6O and KN4PHS like this.
  2. WB5WPA

    WB5WPA Ham Member QRZ Page

    Brevity is the soul of wit ...
     
  3. W4RAV

    W4RAV Ham Member QRZ Page

    Much like any conversation with a room full of people. The likelihood the topics amongst us will drift is high. Particularly if the original subject is already well-covered early.
     
  4. NN2X

    NN2X Premium Subscriber QRZ Page

    Here is why I am a big fan of JS8CALL

    It simply allows the ability to have a QSO at 20wpm at -24dB below the noise floor

    Lets look at other means of working DX

    1. BPSK31 requires at least 6dB above the noise floor to close the link (Along with RTTY)

    Lets say you are using 1,000 watts to close the link, with JS8CALL only required 1 watt to close the link (30DB difference)

    Yes, BPSK31 can work at 50wpm, but now JS8CALL can work at 20wpm. Not bad

    Now lets look at CW

    At very best CW works about -10dB below the noise floor at 20wpm.

    Lets say you are using 200 watts for CW to close a link, all you need you need is 8 watts with JS8CALL (All at 20wpm) (Delta 14DB)

    And we all know the program (And digital modes in general) will continue to advance, this is where the innovation will be for years to come.
     
    KD6SM, G3SEA and N0YPD like this.
  5. K3FHP

    K3FHP XML Subscriber QRZ Page

    Io.groups is a good spot as I believe it offers chat, message and archive resources in one place The instant sign up, easy download of fast coming versions seems to provide easy development for fast coming versions. The downloads are painless, install quickly and easily while providing instant radio interface with no hassles. I think this mode is terrific as it is similar to FSQ, another fav but with ten db more sensitivity. Oh, Girthub has been scooped up by Microsoft I believe.... what could go wrong here?
     
  6. ZS6BV

    ZS6BV Ham Member QRZ Page

    Very cool innovation. Thank you Jordan.
     
  7. KW1NG

    KW1NG Ham Member QRZ Page

    Here's the info file..
     

    Attached Files:

  8. KK5JY

    KK5JY Premium Subscriber QRZ Page

    No.

    A calculated value of -24dB SNR means that the real effective SNR is closer to -18dB. Half the signal is provided out-of-band (the clock). That changes the real SNR value that was achieved by the modem by half, as well.

    If the SNR is being calculated the same way WSJT-X is calculated, it has a number of additional skewed terms added to the SNR (or rather subtracted), as well.
     
    W4MHZ likes this.
  9. WA1ZMS

    WA1ZMS Ham Member QRZ Page

    I have never been a fan of the way WSJT calculates the signal. I fully understand WHY it was done the way it was. Yet when people start using other SW to try and compare the pros & cons of one vs. another, the numbers become skewed.

    >>>Nerd mode = ON<<<

    What I dearly wish people would start to do is to reference the 99% BW of the transmitted signal
    and start using positive SNR values for a given BER %. That's the way I/we talkabout digital comms in the commercial world. We don't reference things to the noise power is some almost arbitrary SSB filter BW. For SSB, sometimes I like 1.8kHz and others 2.9kHz, but somebody else picked 2.2kHz. When/where do you stop?

    kTB = -174dBm/Hz
    SNR = xdB above kTB for a given BER.

    >>>Nerd mode = OFF<<<
     
    N5RFX likes this.
  10. AI6XK

    AI6XK Ham Member QRZ Page

    both FT8 Call, and this new mode require people to create a new login, and forcing you to give them your email address! This is ham radio software, not some email gathering scam... or is it maybe both? I am not going to download either of these until I can download it without having to hand out my email! This seems excruciatingly LAME to me!
     
    KF4ZKU and KN4PHS like this.

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