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WSJT - Is it normal for TX audio frequency to jump?

Discussion in 'Working Different Modes' started by VE3TMT, Oct 29, 2019.

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  1. VE3TMT

    VE3TMT XML Subscriber QRZ Page

    Hi guys,

    When working VP6R on FT8 F&H, I've noticed my TX audio tone change once they come back to my call.

    For example, I'm receiving them on 350Hz and I'm transmitting on same. Even if I have my TX tone set at 350Hz, as soon as VP6R comes back to my call, on my next transmission, my audio tone has now jumped to 2000Hz or something.

    Is this normal?

  2. WA6MHZ

    WA6MHZ Premium Subscriber QRZ Page

    I was just going to post my observation on this as well. I was doing Fox and hound and Calling on 1500HZ When he answered me, my transmit frequency(tone) suddenly went down to about 500HZ. 500 to 1000HZ is the NO MANS LAND on Fox and Hound and serves as a Guard band to keep big signals away from the fox. This didn't do it on the First transmission before he answered me, I tried to reset it back to 1500 Hz and it refused to stay there. It hopped over to 500 HZ again when I was sending the 2nd Message (R-15) to him. I understood they don't receive in the 500 to 1000HZ range so the tone has to be above 1000HZ. He would never hear me answer him with a report and thus I didn't make the contact. What is fishy is things worked fine on 10M thru 80M F and H but not on 160. No the CAT was not shifting my signal down (TX remained on 1832 KHZ). I am still trying to figure this out. SO NO QSO on 160 despite him answering me Twice!!!
  3. ND6M

    ND6M Ham Member QRZ Page

    They DO rx in the 300 to 1000 HZ window,....... BUT,................... ONLY the stations that they move the Tx freq from above 1000 Hx to below 1000 Hz.

    When you moved your TX offset back above 1000 Hz they dropped you and worked someone else.

    from, their web site:

    When you are preparing to work us on FT8, set YOUR transmit frequeny to ABOVE 1000 Hz. IF YOU CALL BELOW 1000 HZ WE WILL NOT HEAR YOU.
    When we make contact with a station, that station’s TX frequency will automatically be moved to below 1000 Hz in a clear window. We will not hear anyone we did not put in the 300 – 1000 Hz window.

    Good Luck
    WQ2H likes this.
  4. VE3TMT

    VE3TMT XML Subscriber QRZ Page

    Explains it, thank you.
  5. N5SMO

    N5SMO Premium Subscriber QRZ Page

    The WSJTx user manual online explains this all in detail BTW.

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