A  COMIC   OPERA

    

Just some observations on the recent posts

 

As  to  the  legality of this  or  any other  digital  mode , the words  of  Gilbert and  Sullivan , in there satire  of the  RN , HMS Pinafore seem's  to fit  as  to the use  of  such thing?s

 

What, never? / No, never! / What, never? / Well, hardly ever!

 

As  pointed out , ?we?  all  use  code  packages that  are  locked , commercial  modem?s  , the parasitic development  and  commercialisation  of  D-Star , the  MS Windows  system being used to  type this  message  are all  locked, so  yes would be nice , but then  so  would many thing?s...

 

My  licence  prohibits the  use  of  secret code or cipher , as the  author is  identified  and the  code my be  freely  downloaded, I hardly regard it?s  use as  a  breach, further  more, with  development  being  undertaken on 500, is that  not what  the experimental  permit was  all  about.

 

Band Co Occupancy,  A the  start  of testing , 500  was  quite  empty , with the split of  allocations  even  wspr  activity from EU had all  but ceased , the  zone occupied at the moment has  traditionally  been used for  data  transmission  in  the  UK.

 

Data  Efficiency

 

The  only  real  test of  data  transmission  is  the  carrier power   required , Gary?s   transmission  to  VO1NA , is  significant , if comparison  is made  with  existing  techniques.

 

The  full  call  sign  was  received  six  times  in a  two  hour  period , using  a  Tx time  of  eight minutes  per cycle  . The  duty  cycle  of  OP is  approx  50% , therefore  , the  total  carrier  required  was   four minutes  .

 

Using    4 minutes of carrier  250 mW  erp   was enough  to  cross  3500 Km  from the  s/n levels  at the rx ,  its possible  that   -3dB lower  could  of been  used  , round  100 mW  .. At the  moment  Opera  offers  a  beacon  mode  with  s/n  performance far in excess  of  existing  systems  with  access  to  all 

 

Surely this opens 136  to  more  users  ?