5 July 2020 -- A revision of a study evaluating Winlink digital modes using the new IONOS HF Path Simulator was published today. Hardware SCS modems running PACTOR 2, 3 and 4 were evaluated as were sound card modes WINMOR, ARDOP and VARA across a variety of channel models and across a range of signal to noise conditions for HF. VARA testing included a new VARA 500 500Hz mode. VARA FM and AX.25/FX.25 packet were simulated for a VHF channel.
Spoiler alert: The SCS modems did very well as you would expect. The much less expensive VARA HF did especially well across the range of conditions tested. The SCS modems and VARA could run long test cases without losing a connection while ARDOP and WINMOR were slower and less reliable for lower SNR MP cases. VARA FM crushed AX.25/FX.25 VHF cases.
The complete paper is available in PDF format from the link below.
--The Winlink Team
