tweaking latency in digital modes ?

Andrew O'Brien

I'm not sure if it is really a SmartSDR issue or not,  but using SmartSDR I am having a timing issue using VARA with Winlink Express.  Using an Icom I do not get this issue.  Winmor works fine with same software but not VARA and SSDR.  It looks extremely close , gaining a few milliseconds could make the difference.  Any suggestions for doing this ?  Seems I am switching to transmit a few milliseconds too early and the gateway and I are not formally connecting.  The mode requires 2.4Khz filter width. I have been using the standard 2.7 under Digu... I am not sure if a custom 2.4 filter would make any difference.  

ANdy K3UK

Paul - K6HR

How about some TX Delay, to slow it down just enough. It's in the settings psnel

Andrew O'Brien

Thanks, will try.  Does the "TX INHIBIT" enable option need to be enabled for TX to start ?

Paul - K6HR

No. Tx inhibit = rx only

Doug Hall

You can try reducing the RX filter latency. In SSDR go to Settings->Radio Setup->Filters and select Low Latency for the mode in question. I'm a little confused - you said you were using a 2.7 kHz filter under DIGU, but that is not one of the selections I have under DIGU, only on SSB.
73,
Doug K4DSP

tpetruzzellis

Andy-I am just trying to setup Winlink with VARA HF Modem on my Flex 6400 - did you ever get your setup to work correctly? I can not seem to establish a link connection - Tom WA2ANG

Andrew O'Brien

Sadly , no . I sold the Flex and got a 7300 . Connected first try to a server I had been trying for weeks to connect to with the 7300. Same when I ran a server , as soon as I tried the Icom users were able to connect to me . I later sold the 7300 and moved up to a 7610 . The 7610 had no issues and this week I got a Icom 705 and was able to connect . I imagine that if ai had worked at it long enough In would have solved the presumed latency issue by adjusting the settings . I tried but lost patience .

Andy K3UK