Hi everyone,
This is a technical post. It updates one of our most popular posts "WinLink Setup with Icom IC-7300".
We'll describe how we setup our IC-7300 HF/SSB to use the new VARA modem protocol on WinLink. VARA offers faster data communication than the older ARDOP and WinMor protocols. One does have to pay the VARA author US$69 to use the high data rates.
Downloading a SailDocs GRIB file |
VARA must be downloaded and installed separately. Download it here. We installed it at C:\apps\VARA but the default is C:\VARA.
With VARA installed open WinLink Express. To setup VARA open a 'Vara HF WinLink' session. Configure Settings ... VARA TNC Setup and then Settings ... Radio Settings as below...
VARA TNC Setup |
Radio Settings |
Key to configuring VARA is setting audio levels. Setting microphone (Rx) level is easy since VARA provides a VU meter. For us, speaker (Tx) level was harder.
Initially 'Tuning' using the VARA SoundCard drive level tool caused interference in the USB cable which confused the IC-7300. Once we realised what was happening it was simple to re-run the USB cable via a quieter path (it was already fitted with RF chokes) and set the volume. We settled on a lower volume than the graphic in the tool recommends.
Setting VARA Tx Level |
Transmitting VARA |
VARA session with Speaker Volume Mixer |
Starting session to download GRIB email |
GRIB email download in progress |
5700 Bytes/Minute download speed |
It's interesting that VARA can exceed 20kBytes/Minute in reasonable conditions. That's faster than Pactor3 or Iridium Go!.
We expect to use HF/SSB WinLink as a backup to an Iridium Go!. One reason for this is we like PredictWind forecasts and routing. PredictWind data can't be carried over WinLink since it is commercial.