so ive been trying to get Winlink working for about two weeks now and im losing my mind a little. running Winlink Express on a windows 10 box, got a Signalink USB into my IC-7300, and im using VARA HF for the connection. i can see the RMS gateways in the list, pick one thats got decent signal, initiate the session, it handshakes fine and then somewhere in the middle of actually sending the message it just... drops. the little progress bar gets maybe 40-60% and then the session terminates and the message sits in my outbox.

ive tried three different gateways at this point, two of which were under 200 miles away so path shouldnt be the issue. my VARA soundcard levels look okay to me - the TX is showing around 70% in the VARA setup screen which i thought was the recommended range. not sure if this is a timing issue, a power issue, something with the 7300 settings, or what. the IC-7300 is set to USB-D and data mode is on. ALC is barely moving.

anybody dealt with this? feels like its almost working which is somehow more frustrating than it just flat out not connecting at all.

yeah that 40-60% drop is almost always a timing or audio level thing in my experience. first thing id check is whether your IC-7300 has the USB send/keying set up right in the menu - theres a setting for DATA MOD that needs to point to USB and not the front mic. if its double-keying or theres any audio bleed from the front panel thats enough to corrupt the packet mid-transfer.

also VARA HF at 70% TX sounds fine on paper but sometimes the actual output from the radio is too hot even if VARA thinks its okay. try pulling it back to 50-55% and see if you get cleaner handshakes. the Signalink has its own TX knob too - people forget that and end up with the two gains fighting each other. what do your waterfall tones look like? if theyre splashing or distorting at all thatll kill a session every time. the RMS gateway will just bail if it sees garbage.

dont overlook the gateway itself honestly. some of the RMS nodes you see in the list havent been maintained great and they'll accept a connection then flake out. i had something similar and eventually just signed up for a VARA-FM session through a local node on 2m instead and it worked first try. not saying thats your permanent fix but it helped me figure out if the problem was on my end or the gateway end.

also check your Windows audio settings - theres a known thing where Windows will decide to "enhance" the USB audio device and it completely wrecks the VARA tones. go into sound settings for the Signalink device and make sure all the enhancements are turned off and the sample rate is 48000hz not whatever Windows defaults to.