Re: New VARA HF v3.0.2 #VARA

Andrew O'Brien
 

Thanks Graham, I have downloaded and it installed without issues.  Seems my registration from previous versions has been accepted.   I'm not actually sure how to use since almost all my previous use was with RMS Express.  I am not sure if there is again a stand alone use, will poke around some more.

Andy K3UK

On Mon, Jul 22, 2019 at 4:12 PM Graham <g0nbd@...> wrote:
Andy, 

I think  you  may find , the  new  'Chat' application , quite novel, in that  it gives access to the  modem at  all  speeds ,  but , I for  one  cannot  type that  fast ! , running the  'chat  app , calls the  vara  modem ,
Chat provides the  Rig  control  , via CAT or  Com-ptt  and the  modem  , the  audio interface  and  tune  button  ,  now a single  1500 Hz test  tone .The new modem has improved low  signal performance ,  this with the  arq  function , makes  for  low  power  error free  qso's , at power levels  much reduced  from the  days of amtor

Though not intended ,  the  unlicensed [free for all]  modem runs to  175  baud  level 3  , min being 40 baud  , ample  for  qso ,  but notably ,  for the  qrp  users , the  modem  remains  MFSK as  is the  ACK frame , being  phase continuous , allows it to be  passed  via non linear systems , ie , class  E/D  power  stages , which will  be of interest to the  low power / battery  emergency  situations ,  

Entering a valid key , enables the  faster  levels, which are ofdm and require  linear handling.

Might be of wider  interest to list  possible watering  holes  for  'vara chat' ? first over the  pond  might be a start !

73-Graham
g0nbd



--
Andy

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