Hi Graham!
Many thanks for Your very comprehensive explanation & links! :)
vy73
Dennis
-----Ursprüngliche Nachricht-----
Gesendet: Sonntag, 04 Januar 2015 um 02:05:35 Uhr
Von: Graham <[email protected]>
An: [email protected]
Betreff: Re: LF: OPERA explanation?
There is a description of the data encoding in the yahoo group ,
along with the last working version one-4-one , 15 chrs plain
text 120 second tx time version , alas only -20 dB s/n
originally developed as a plug in replacement for the CW key ,
later the beacon function found extended use across most bands in use
,
Other than that , its a serial data mode , using Manchester coding ,
transmission is by on/off keying of a single carrier , FEC and AFC
provide additional sensitivity and negates the need for high
stability tx/rx , originally 50% of the signal needed to be recovered
for decode , this is now app 40% , ie 60% random loss can occur.
Its packaged as a stand alone windows application , that provides
tx/rx and web linkage to other users and the psk-map
the tx cycle time is used to increase the sensitivity , changes to
the DSP are provided , linked to band, to accommodate changes of
requirements , the longer op8/16/32 1H 2H [4H audio sound card sdr]
being suited to low frequency , where as the Op4/2/1 best fit HF ,
the more experimental Op05 [ 30 second -20 dB] finding good use , 145
MHZ up to 10 GHz
The 'Crazy Gang' in EA , regularly see 500 + K 2/ 70cm / 23 cm ,some
times 1500 K on 2 meters
EB6AOK EA9MH 2m OPERA 575 km 19:01:00
EA9MH EB6AOK 2m OPERA 575 km 20:28:55
EA3KZ EA5CV 2m OPERA 419 km 10:04:01
EA5HNM EA3KZ 2m OPERA 415 km 19:59:01
EA3KZ EA5HNM 2m OPERA 415 km 15:05:16
EA3KZ EA5CV/P 2m OPERA 407 km 20:12:53
EA9MH EA5CV 2m OPERA 405 km 07:49:16
https://www.facebook.com/groups/operadatamode/
https://groups.yahoo.com/neo/groups/O_P_E_R_A_/info
73-Graham
G0NBD
--------------------------------------------------
From: <[email protected]>
Sent: Saturday, January 03, 2015 11:37 PM
To: <[email protected]>
Subject: LF: OPERA explanation?
> OPERA digimode:
> Where can I find a good explanation.
>
> Search engine = OPERA G4WGT
> didn't help.
>
>
> 73 Dennis
> DL6NVC
>
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