JT65 – mostly

I spent a couple of hours yesterday with WSJT-X trying to make some contacts by answering CQs and getting nowhere. After a lot of fiddling with settings (I spotted the ALC on the FT450D was going haywire – who’d have though it had a display!) I now have much better settings of sound system output and Tx control on the SignaLink. The Tx is now set to just below to 9 o’clock position, so almost to the third tick mark, and the sound system output is set to 29% via the Pulseaudio volume control. The power setting in WSJT-X is set to -0.9db at which level the signal still triggers the PTT relay in the SignaLink but at 100% (-0db) the ALC triggers. But no luck with answering CQs.

Actually the Pulseaudio setting threw me at first because WSJT-X uses ALSA, but the ALSAmixer shows the same 29% as set by Pulseaudio so I’m not fussing. Also, it still gives the expected power output on the PS modes and a test call on BPSK31 worked fine, so it’s all be written down.

And today I got a reply to my reply to a CQ. But it was confusing. WSJT-X has two windows, one for Band Activity and one for Rx Frequency. It’s all made very easy, you double-click on a CQ in the band Activity window and it moves your Tx and Rx frequencies to that station and pre-fills standard messages. The system can also be set to enable Tx when you click but I’ve not done this. There is time (seconds) between clicking the callsign, checking everything is ok and clicking Enable Tx.

So back to my first JT65 QSO. I clicked on a CQ as above and clicked Enable Tx and off went my reply. Remember these take a full minute each, with replies coming in a few seconds ahead of the minute mark, and everyone’s clock must be very accurate or it does not work. Well, the next message from the CQ’ing station, the reply to me showing my remotely received signal strength came on a different frequency. So it displayed in the Band Activity window and not the Rx window as I had expected. But it was a valid reply and so my next one went out – my reply including R-xx, R for received and the -xx being the strength of the station as received by me. The next message from the remote station was the same as the previous, i.e. my signal strength as received. So I halted the transmission there assuming I had got something wrong.

So not a complete QSO  but I received an eQSL card for it and so I am counting it as my first ever on JT65, and it proves my system works.

Anyway I persevered amongst other things and managed a complete JT65 QSO later in the day, but the replies still came back in the Band Activity window on a different frequency than my transmissions, and the original CQ that I answered still showing in the Rx Frequency window. Why the difference? The QSO ran fine, all messages exchanges right to the 73’s. When I can see both sides of other QSOs, or even the relevant bits they all appear at the same frequency. (note ‘frequency’ here is that displayed by WSJT-X in Hz, not the dial frequency)