TX Delay in WSJT-X

va7qi

When I run FT8 on the 6600M I notice that the TX takes 1-2 seconds to kick in. Any of my other rigs start transmitting immediately. I have TX delay set to 20 mS in the Transmit screen.

WSJT-x is set to use the virtual serial CAT control and PTT uses CAT.

Have I missed a setting?

73 de va7qi, ....Erik.

David Decoons, wo2x

Look at WSJT-X settings/advanced. It is set to 2 seconds as default.

I forget why but you might reach out to Mike W9MDB. He is on the WSJT-X development team.

mine is at default and when so have monitor on my radio starts transmitting with almost everyone else (there are differences depending on PC clock). Make sure you use a program to sync your PC time like Dimension 4 or another time sync program.

Also in radio settings tab of WSJT-X you should use the Flex 6xxx radio and in IP field enter 137.0.0.1:5004

In SmartSDR CAT make a new CAT port that is TCP and enter 5004 for port number. Also set mode to digital/packet. If your TX bandwidth is set to 100-3000 then you can leave split alone or set it to Fake It. Fake It mode keeps your TX frequency between 1500 and 2000 Hz even when ESKT-X is set to something outside that range. On other model radios this helps reduce harmonics by keeping TX audio harmonics outside TX passband. And one some radios they can be as little as 300-2700 Hz TX passband for 6 dB roll off point. You would see a drop in TX power at lower or higher TX audio frequencies.

Hope this helps.

Dave wo2x

Ted VE3TRQ

Slight mis-type there, Dave:

”Also in radio settings tab of WSJT-X you should use the Flex 6xxx radio and in IP field enter 137.0.0.1:5004”

should be:

”Also in radio settings tab of WSJT-X you should use the Flex 6xxx radio and in IP field enter 127.0.0.1:5004”

David Decoons, wo2x

Thanks Ted. I “**** fingered” it.

;-)

Dave wo2x

va7qi

Thanks Dave & Ted,

I was using a VSP for CAT. My TCP default setting in CAT uses 5002, so that is what I using in WSJT-x. The TX delay setting in WSJT-x has been 0.1 sec for a long time.

I am set up with GPS-derived time on the PC. I have worked a lot of FT8 :-)

The passband on the Flex seems quite flat. I had a bad experience with the Yaesu FTDX10, which required regular adjustment of output power depending on where in the passband I transmitted. I still use the FTDX10 on 6m, but try to stay in one small part of the band.

Anyway, I did a quick test with the TCP CAT and it seems to good now. Interesting, though, the serial CAT worked fine with Winlink/Vara.

73 de va7qi, ....Erik.

Ted VE3TRQ

“Interesting, though, the serial CAT worked fine with Winlink/Vara.”

Erik, that part of your comment intrigues me more than the rest of your message. We have been trying to use our Flex radios to do VARA HF P2P and Winlink, and find the latency such that we cannot communicate between two Flex radios, although Flex to non-Flex works OK. What has been your experience?

Thanks for any insight.

va7qi

Hi Ted,

I can't say I have used Winlink a lot with this radio, but just for fun I connected to three different stations tonight and they all worked well. I have the Vara license, so it goes up to near full speed and I did not notice any lost transmissions, but conditions were good tonight. WL Express still uses the serial CAT method since I did not change it for the test.

The computer is a two-year old Intel I5 something with 8 GB RAM and only firefox running in addition to 'Express. I never run P2P, BTW.

73 de va7qi, ....Erik.

David Decoons, wo2x

I bet the FTdx10 has a lot narrower TX bandwidth and as you get close to the bandwidth edges the TX power will drop. Also would be interested to know the TX filter specs on the Yaesu.

The Flex TX filters have a sharper filter shape and thus a flatter bandwidth.

Glad the TCP connection for WSJT-X is working for you.

Dave wo2x

Ted VE3TRQ

“I can't say I have used Winlink a lot with this radio, but just for fun I connected to three different stations tonight and they all worked well.

I never run P2P, BTW.”

Thanks Erik. I suspect most all the RMS stations out there are not running SDR radios, so your Flex will work with them. Our experience is that a Flex with VARA will not connect to another Flex running VARA (in P2P mode), but will connect to a non-SDR radio:-(