Locked Re: Frequency shifts down 500KHz on transmit #FT8

Bill Somerville

On 12/05/2021 21:34, John wrote:
Everything was working great, WSJTX, JTAlert and HRD LogBook.
Then there were no decodes the next operating session, no Windows updates to interfere.

I hear and see loads of signals but no activity is shown in the RX pane, the DECODE light flashes now and then, but still no decodes.

I have to confess, I didn't really notice if this is normal for the VFO to shift 500KHz down on transmit, is this normal?

Any help would be appreciated.

FTdx-3000, Yaesu web site drivers, Win 10 Ver 20H2, OS build 19042.964

Hi John,

it is normal for WSJT-X to shift the Tx VFO dial frequency according to the Tx audio offset you choose, it is done to ensure your signal is as clean and free from audio harmonics as possible. The on-air frequency of your signal is not affected as WSJT-X compensates by adjusting the Tx audio tone frequencies.

A lack of any  decodes is usually down to one of two factors:

1) you are using the wrong sideband, WSJT-X expects USB for Tx and Rx,

2) your PC time is not well enough synchronized to UTC, within 1.5 seconds is sufficient for all modes in WSJT-X. Nn MS Windows that does not happen automatically and you need to install a tool to do that for you. Installing a tool like the Meinberg NTP Client (as suggested in the WSJT-X User Guide installation instructions for MS Windows) will get that done for you.


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