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First ROS test over QO-100 Sat #ros #sat #qrp

Graham
 
Edited

First ROS test over QO-100  Sat #ros #sat #qrp

PA1SDB Condcted a QRP test over the  Sat link, using the  goonhilly  web-based sdr  for  RX
Of ROS-4  and Thor-4  data  modes  

Using  a  carrier level of  1.5 mW , to 95 cm Dish  for the  2.4 Ghz up link ,  , 
running  at   -22 / -23  dB s/n  [ 2.4 Khz b/w] average of the  tx time line  this  was at the  lower limit of the 
8 baud  ROS-4_HF mode , 

[ It was not  noted  till  post test, that  ROS-4  is  actually effective  8 baud  , 
compared to Thor 4  , being  4-baud  , ie effective  + 3 dB gain] 

With carrier level of 1.5 mW  , one error free  decode was achieved  ,  <crc-ok>  -22 
with partial decodes ,  at -23 dB ,  The tx  text  is not  recorded 




Using the  same  1.5 mW , similar text loss  occurred  using the  Thor-4  mode ,  though  , no indication is provided  as to  correct  decode ,  by  crc  check 

Noting that  Thor  at 4  baud , presented a  theoretical advantage of + 3 dB , due to  baud rate  being  50% 




Notes  on the  test . 

Unlike Opera ,  ROS remains the  same  for  all  bands ,  the  2  meter band is recommended to  separate  reporting as  best  as possible 

At -22 dB s/n  , an increase  of  +2  or +3 dB  power , ie to  3 mW would  of  produced 100% copy  in ros-4 ,  + 6 dB 12 mW  qso at  normal typing  speed  ,  ros-8  and  at  48 mW that would  enable ros-16 

More unstable equipment , Use of the  Highest  speed  is  recommended , 

Dial set Rx No QRG is reported, but, noting, being 2G , and  self  sync,  once a watering  hole is  'spotted , then  only that  dial usb setting  need  be used ,  as  all  traffic may co-occupy  the  same channel , at the  same QRP  power levels , probably best  demonstrated by the  27 MHz users , during  good  propagation,local and dx   all  activity  is  confined to  single channel , this from 2015 




73-Graham
G0NBD

Siegfried Jackstien
 

hello graham

thanks for the repot of qrppp usable on the new sat

so ... you can grab a pluto without amp behind it ... and can do ros and have a good copy???

wow that is nice

...

today i was doing some bench testing of my new 10w amp

good for ssb .... maybe a bit to low power for datv

hope to be on the sat next weekend

greetz sigi dg9bfc

Am 09.04.2019 um 19:45 schrieb Graham:

First ROS test over QO-100  Sat #ros #sat #qrp

PA1SDB Condcted a QRP test over the  Sat link, using the  goonhilly  web-based sdr  for  RX
Of ROS-4  and Thor-4  data  modes  

Using  a  carrier level of  1.5 mW , to 95 cm Dish  for the  2.4 Ghz up link ,  , 
running  at   -22 / -23  dB s/n  [ 2.4 Khz b/w] average of the  tx time line  this  was at the  lower limit of the 
8 baud  ROS-4_HF mode , 

[ It was not  noted  till  post test, that  ROS-4  is  actually effective  8 baud  , 
compared to Thor 4  , being  4-baud  , ie effective  + 3 dB gain] 

With carrier level of 1.5 mW  , one error free  decode was achieved  ,  <crc-ok>  -22 
with partial decodes ,  at -23 dB ,  The tx  text  is not  recorded 




Using the  same  1.5 mW , similar text loss  occurred  using the  Thor-4  mode ,  though  , no indication is provided  as to  correct  decode ,  by  crc  check 

Noting that  Thor  at 4  baud , presented a  theoretical advantage of + 3 dB , due to  baud rate  being  50% 




Notes  on the  test . 

Unlike Opera ,  ROS remains the  same  for  all  bands ,  the  2  meter band is recommended to  separate  reporting as  best  as possible 

At -22 dB s/n  , an increase  of  +2  or +3 dB  power , ie to  3 mW would  of  produced 100% copy  in ros-4 ,  + 6 dB 12 mW  qso at  normal typing  speed  ,  ros-8  and  at  48 mW that would  enable ros-16 

More unstable equipment , Use of the  Highest  speed  is  recommended , 

Dial set Rx No QRG is reported, but, noting, being 2G , and  self  sync,  once a watering  hole is  'spotted , then  only that  dial usb setting  need  be used ,  as  all  traffic may co-occupy  the  same channel , at the  same QRP  power levels , probably best  demonstrated by the  27 MHz users , during  good  propagation,local and dx   all  activity  is  confined to  single channel , this from 2015 




73-Graham
G0NBD

Graham
 
Edited

Hi Siegfried,

Yes, the  power levels are quite  unexpected ,  at the moment ,  100  mW to 95 cm dish is  producing  - 5 db s/n/ , with 25 % signal loss , we don't know , if the  'spread/loss  is  from the  2.4 , 10  or both  links ..thats  well inside the  ros-16 s/n 

23:56 1296600 PA1SDB de SV8RV Op05 1264 mi -5 dB F:25% in [D] Zakynthos(Zante)isl.GREECE via OSCAR-100 100mw 1507,8 Hz with 2

Ea5dom  , reached  this level  with  20w  or so,   watts  to a co linear ,  360  deg  radiation pattern ! may be 5  watts  , would be  enough , basically  if  opera op05  decodes , the  link  will  support  ros-4 

SV8RV Has added  Opera op05   live  off air decodes  , to  his list of monitored channels ,  so, if you  want to  check you  Ae  alignment  etc ,   the  up link  carrier  frequency  needed  is 2.400106 GHz , use the  1296  setting  on the  opera app , and  either  cw key  or  audio  drive  [ fixed at 1500 Hz ]  , but make sure the  on-air carrier  frequency is  correct, the  Opera  decoder is  quite wide [ +/- 200 Hz on 1500 mid band]  , the system will  spot  you  , or  you  can  monitor  locally  off  air  . or the  web-sdr ,  QRG  10.489603.500 GHz USB

It would be  useful  to compare , single  tone s/n  from your tx to  ssb , to  get a  measure  as to power needed  for  voice 

GL  73 -G

Graham
 

First live  Two  way  QSO's  reported  on 10.489606  GHz  Down  link  frequency 
Between  PA1DSB and  SV8RV   ,  QSO  using  off  air  10 GHz Rx  each side  of the 
qso  and  1 meter . and 94 cm  dish tx/rx , { ROS is listed in ADIF ]

Its suggested that  the  Dial-set-USB for  ROS QSO is  10.489606  GHz
SV8RV  and others are now monitoring  . 

73-Graham
g0nbd

Peter reports ,  power levels  for up link of  10mW to  95 cm Dish , 

 
I Just was in QSO with 8RV. We did start in TX4. Later TX16. I think power was 10mW into 95cm dis here. But i have to do some measurements.

Screen  capture  of  QSO text,  showing  -13  <crc=ok>  ie   100 % copy 





psk-map  showing  as 2 meters , being the  highest band 
set in the  ROS  applications ,  as  Opera ,  based on  psk-map