QSP from VARA site, news of new features and functions .
Some insight to the USAF adoption , round compression rates
and BBS connect times ,
10 Apr 2021, 16:20:45
to VARA HF Modem
New VARA HF v4.4.3 released:
The previous release versions of VARA uses a 16-bit hash to resolve the callsign and this has a small but finite chance of getting the call wrong (One in 6553 error rate). John Wiseman detected and reported a case he observed this happening.
Now this is changed to a 32-bit representation which will essentially eliminate the chance of this happening.
VARA Compression added, which reduces connect overhead's for weak signal conditions. Averaged simulation runs showed improvements of a factor of 2 in the Speed Level 1. The improvement becomes more modest as the SNR is improved until Speed Level 6, where compression is not necessary. Messages which already have Winlink applied B2F compression are not compressed.
Compression also accelerates dramatically the BBS throughput (using VARA Terminal v1.1.5).
Thus, BBS Lists are accelerated by 3.0, Forecast messages by 2.6 and MARS Encrypted Data by 1.5. For more info about how use VARA Terminal for BBS MARS connections, contact with Dave AF2HV (Squadron Commander, 22nd AFMARS Trans-Global Communications Digital Operations Military Auxiliary Radio System, USAF)
This great feature is active only for the registered users and was added a few days ago to VARA SAT v4.1.0. and , will be embodied in VARA FM soon.