Re: VARA HF , TRI MODE and the SDR #SDR #VARA


Graham
 

Ok  James's 

Good  question, 

The Trimode  Dwell  time  of   4 seconds ,  is the  'only' limiting  factor , preventing the  deployment  of   SDR   in a   gateway 
which is perhaps a legacy issue .. 

Unlike 'fixed'/'static'  timed  systems / protocols , Processing  delays  and  switching times  are  not critical,  the  Vara  modem  deploys  'Dynamic' timing , additional delays [symmetrical & asymmetrical]
are automatically  compensated  for . eg  repeater  delays  for  VHF/FM and the  long  path delay  , for the AO-100   Sat link version  [ which also  can be used for  HF etc ]  , leaving the  HF version, while  compatible with the  4 second  dwell requirement ,unable to provided  otherwise,  sdr<>sdr connectivity 

Established: 

The  limiting  factor  is  solely the  4 seconds  delay , [as to  why  '4' seconds  is required
is not  clear ?] .  

Increasing the  Dwell  time  by  500mS  , to  4.5  seconds , would  allow  deployment of the   Vara HF
modem , inside the  Trimode  system and  provide  both  SDR<>SDR and  Hybrid connectivity 
both  inside and  out side the  winlink  system.

73-Graham
g0nbd



Join main@digitalradio.groups.io to automatically receive all group messages.