I'm having persistent problems with VARA HF connections timing out during the initial handshake. So far I have it "working" in that it can initiate a session, and I hear the other station responding with good signal level, but no connect. Then it times out... The connection sequence requires a very quick tx/rx turnaround. Until very recently (after Flex did some work on reducing digital signal latency) you couldn't get two Flex radios (6000's) connecting.

My setup is IC-7300 with built-in USB interface running VARA HF 4.9.0 and Winlink Express 1.7.4.0. I am having the same issue Ken was having with the timeout happening then an endless closing and opening of the session window... I have been working on getting Vara HF to work with my Flex 6500, but I am experiencing what alot of these other users are which is timeout happening after an endless closing and opening of the session window. Audio levels look good, PTT is working, but something in the protocol handshake is failing. Any specific settings I should check?

I removed all the TCP ports and it started working - try clearing any extra COM/TCP port assignments in both VARA and Winlink settings. Also verify your IC-7300 is set to DATA-USB mode, not USB-DATA, and confirm CI-V address matches between radio and software.

Latency is critical for VARA connections. You need to do everything you can to reduce delays. Of course you are using a 3000 with PSDR, so things are different, but the need for low latency does not change. On the IC-7300, try turning off any DSP noise reduction, set the USB audio sample rate to 48kHz, and use the shortest possible USB cable.

Check your VARA HF log files - they'll show exactly where the handshake is failing. The VARA HF and radio settings are the same as while using Winlink Express... CAT control apparently works the way it should, frequency setting/readout and PTT works fine. If CAT is working but connections fail, it's usually an audio routing or timing issue.