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New VARA HF released 4-3-0 #VARA


Graham
 

On Sat, Jan 2, 2021 at 05:16 PM, Siegfried Jackstien wrote:
nobody would moan about using 2.9kc ...
Hi Sigi ,  The  channel  could be  2.9 k , the VTAC  modem is 2.795  KHz  
but  probably would not  work, due to the  circuit delays 

VSAT is based on the 2KHz b/w  HF modem 
and supports the  extended  delay and provides
auto  capture and net ... 

May be when the  Moon  repeater is  installed , 
the 4 seconds will  also be catered for -)

73-Graham 


Graham
 

Apparently it's 'listed in the beta version , not yet embodied in the current release.

73 Graham 
G0nbd


James Clark
 

Is selection of the new 2750 mode automatic?

When I start my registered copy of Vara V4.3.0 with Winlink Express V1.5.33.0 the speed displayed below the Vara waterfall is 2300 and I cannot find a method to select 2750, Winlink Express permits switching between 2300 and 500 but nothing else?


Graham
 

Interesting  Andy 

Any of the  VARA modes will  run over  FM link ,  during testing , with  local station on 6 metres ,  who , was suffering from  solar panel  qrm ,  during the  day, 'we found that  switching to  FM gave a  significant speed  improvement 

VARA-FM  , has  ' No Afc' , as is not needed  for fm link ,  as the  recovered  tone  range is  not  affected by the  transmission , Hence  'designated  'fm'   But ,  variations on the  theme , could be   AM , or pilot tone ssb ?  the FM mode  has  much higher tolerance to switching times , to accomodate  repeater  usage , so, yes , will  be ideally suited for MARS  usage , 

Considerable work was carried out , modifying the  vara-hf  mode to vara-sat , to use with the  ao-100   satellite , providing a  ping system, that  measured the  frequency off  set  and the  link  'round' delay time.. the  tests  where  posted to  one of the  amsat groups , not sure if the  ground  station  remains active ?

73-Graham 

nb: this version , could be  used for  any transmission  path,  I don't think there  is a  minimum delay .. 



Andrew OBrien
 

Yes Graham . I just received a private email from USA air force MARS person interested in testing VARA FM on MARS repeaters . Interesting idea . 

Andy


On Jan 2, 2021, at 1:02 PM, Graham <g0nbd@...> wrote:

HNY Andy

Yes , just the  same as  the  other  vara  HF modes ,  the  individual  carrier rates  are  42  baud , 
300 never really  made much sense, other than  b/w linked to  speed / rate , far to high to  be robust
on HF ..but yes, crazy amounts of data  in a speech channel  , nearly as  quick as the  old  9600  on UHF 

Seems  to  be being  driven by the  emergency  &  ham<>mil  users  ..?

73 -Graham
G0NBD


Siegfried Jackstien
 

an fm signal is way narrower as the tv datv signals is so you will have a way higher signal as the tv beacon (and other user will be a bit "pissed") ... on the other way if you lower your level to the same as the tv beacon ... its then only a few db over noise giving not enough signal to noise for a good fm decoding/demodulation ... so using the wideband transponder does not work

a well tuned setup should be spot on (also on qo100) ... how much mistune can the modem handle (if used on normal ssb mode?!?

if say 50 hz plusminus is ok ... then also netting should work in vara mode on the narrowband transponder ... if not in the new 2.9 kc wide mode ... then use the 2.3 kc mode ... that should work in any case

extended afc in vara sat?? ok then they arelready dealt with the mistune (and the time delay over the qo100 sat)

i did not try it yet ... so i can not say details or how well it works ...

HNY graham

greetz sigi dg9bfc

Am 02.01.2021 um 17:55 schrieb Graham:

HNY  Sigi

Well ,  AO-100  has wide and narrow  band  areas, there  are  already  VARA SAT , which has  extended AFC and some 
link delay measuring  modules as well  , will  also  work with  any  steam powered  ssb set ups that  need  very long tx/rx times  , that is   more  suited to  the  sat link, as was designed  specially  for the  sat , but ,  no reason why the  high speed  varafm-96  could not be  used in the  wide band  section ? I would think the  power density of a wide band  FM signal  is similar to the  TV  broadcasts  ? and    zero  netting problems  ,  being  fm ?

73 -Graham
g0nbd

Ive never seen the  AO-100   transponders full ,  there  is a  ROS-HF mode  qso  running, with  prog set to  2 meters  
no different to the  on-air modem, just the  highest  qrg  coded  these days  .. and with  ROS -HF more than one  qso  can be  running at the same time  in the  same channel 


Graham
 

HNY Andy

Yes , just the  same as  the  other  vara  HF modes ,  the  individual  carrier rates  are  42  baud , 
300 never really  made much sense, other than  b/w linked to  speed / rate , far to high to  be robust
on HF ..but yes, crazy amounts of data  in a speech channel  , nearly as  quick as the  old  9600  on UHF 

Seems  to  be being  driven by the  emergency  &  ham<>mil  users  ..?

73 -Graham
G0NBD


Graham
 

HNY  Sigi

Well ,  AO-100  has wide and narrow  band  areas, there  are  already  VARA SAT , which has  extended AFC and some 
link delay measuring  modules as well  , will  also  work with  any  steam powered  ssb set ups that  need  very long tx/rx times  , that is   more  suited to  the  sat link, as was designed  specially  for the  sat , but ,  no reason why the  high speed  varafm-96  could not be  used in the  wide band  section ? I would think the  power density of a wide band  FM signal  is similar to the  TV  broadcasts  ? and    zero  netting problems  ,  being  fm ?

73 -Graham
g0nbd

Ive never seen the  AO-100   transponders full ,  there  is a  ROS-HF mode  qso  running, with  prog set to  2 meters  
no different to the  on-air modem, just the  highest  qrg  coded  these days  .. and with  ROS -HF more than one  qso  can be  running at the same time  in the  same channel 


Andrew O'Brien
 

does this keep us in the USA "legal" in terms of FCC imposed baud rates.  I can't remember those pesky rules
ANdy K3UK

On Sat, Jan 2, 2021 at 12:16 PM Siegfried Jackstien <siegfried.jackstien@...> wrote:

hmm .. its a tad bit wide to be used on qo100 ;-) ... ok ok its vara HF ... not vara shf hi hi

100 to 2900 ... sure can you set that in your sdr setup (example a pluto) ... but we should not use more as 2.7 there ... hmmm

on the other hand there are stations splattering as wide as a barn door so as long as we keep it linear and not splattering then i guess nobody would moan about using 2.9kc ...

wow ... not bad ... 8.5k in a 2.9 kc wide channel ...

greetz sigi dg9bfc

Am 02.01.2021 um 14:54 schrieb Graham:
New VARA HF released  4-3-0

New for  2021 ,  additional  2750 Hz bandwidth  mode added  to the  VARA  family 
utilising available  bandwidth,  maximum rate is  increased to 8489  Bps in 2750 Hz 
centered on 1500 Hz mid point  tone.

The  Modem architecture , being optimised to maximise the  available bandwidth
with  new  carrier number's / bps rate  combinations, all the  facilities of the  VARA
system are maintained , monitor , chat module, bps , and  winlink connectivity.

Note the  level numbers are, then, not directly related 



Compatibility with  existing  installations is  maintained  , by automatic
mode detection , as  per  existing 2300 <>500  mode  switching .





Rig compatibility ,  ic7300  may be  directly  set  to the  required b/w, where  as the  ic7100   , requires the  use of the  SSB voice  
non  standard  bandwidth  settings  of 100 Hz <> 2900 Hz , further  details are  contained in the  pdf documentation 

73 -Graham
g0nbd





--
Andy


Siegfried Jackstien
 

hmm .. its a tad bit wide to be used on qo100 ;-) ... ok ok its vara HF ... not vara shf hi hi

100 to 2900 ... sure can you set that in your sdr setup (example a pluto) ... but we should not use more as 2.7 there ... hmmm

on the other hand there are stations splattering as wide as a barn door so as long as we keep it linear and not splattering then i guess nobody would moan about using 2.9kc ...

wow ... not bad ... 8.5k in a 2.9 kc wide channel ...

greetz sigi dg9bfc

Am 02.01.2021 um 14:54 schrieb Graham:

New VARA HF released  4-3-0

New for  2021 ,  additional  2750 Hz bandwidth  mode added  to the  VARA  family 
utilising available  bandwidth,  maximum rate is  increased to 8489  Bps in 2750 Hz 
centered on 1500 Hz mid point  tone.

The  Modem architecture , being optimised to maximise the  available bandwidth
with  new  carrier number's / bps rate  combinations, all the  facilities of the  VARA
system are maintained , monitor , chat module, bps , and  winlink connectivity.

Note the  level numbers are, then, not directly related 



Compatibility with  existing  installations is  maintained  , by automatic
mode detection , as  per  existing 2300 <>500  mode  switching .





Rig compatibility ,  ic7300  may be  directly  set  to the  required b/w, where  as the  ic7100   , requires the  use of the  SSB voice  
non  standard  bandwidth  settings  of 100 Hz <> 2900 Hz , further  details are  contained in the  pdf documentation 

73 -Graham
g0nbd




Graham
 

New VARA HF released  4-3-0

New for  2021 ,  additional  2750 Hz bandwidth  mode added  to the  VARA  family 
utilising available  bandwidth,  maximum rate is  increased to 8489  Bps in 2750 Hz 
centered on 1500 Hz mid point  tone.

The  Modem architecture , being optimised to maximise the  available bandwidth
with  new  carrier number's / bps rate  combinations, all the  facilities of the  VARA
system are maintained , monitor , chat module, bps , and  winlink connectivity.

Note the  level numbers are, then, not directly related 



Compatibility with  existing  installations is  maintained  , by automatic
mode detection , as  per  existing 2300 <>500  mode  switching .





Rig compatibility ,  ic7300  may be  directly  set  to the  required b/w, where  as the  ic7100   , requires the  use of the  SSB voice  
non  standard  bandwidth  settings  of 100 Hz <> 2900 Hz , further  details are  contained in the  pdf documentation 

73 -Graham
g0nbd