After
some time in development the 136/500 version
of the Opera data mode is ready
for experimental use .
Download links are
available from myself or Gary, G4WGT as the
versions may change , these may also
change ,
Users are invited to join
the Opera yahoo group http://groups.yahoo.com/group/O_P_E_R_A_/?yguid=131323118
At the moment , spots are
distributed to other OP users on line at the time ,.
future intent is to link to the
PSK-Reporting network and for a HF version
and possible limited QSO mode , allowing
under the noise qso's with a simple
xtal tx
There is a on line chat
mode to facilitate tests etc
The software is available
for all , free to use ,
Happy new year to all
and good luck
73-G ..
OPERA The new CW/ QRSS replacement data mode
There is
always the assumption
that all armature radio stations can effectively translate what ever new soundcard data mode that is
coded to radio frequency..
The question I posed was ?What about those who cannot , and only have CW transmission facility?s??
?
Never did get a
reply
So
after a long exchange of emails , the concept of
a serial data mode that used only one tone , on/off keyed , with a eye on the qrss system, was finally discussed and coding work begun, an initial statement that in software , could be achieved a lower level of
detection than that required to produce a line on a spectrum plot set the scene for a
what was originally proposed to be a simple data mode, turned into to a
race to the noise floor.
OPERA
Is
a totally new Data / Beacon mode , profiled for the 136 and 500 bands , with HF
possibility?s
later in the project . The beacon mode is the version
under test at the moment.
Opera was designed as an alternative to the QRSS transmission system and provides for a limited number of characters to be
transmitted by a serial single keyed tone , as is
QRSS or live CW, 6 at the moment.
It is live ?data? mode and there is
no requirement for time synchronisation of the tx/rx station .
The mode can be
transmitted by any transmitter SSB/CW , there being provided a
keyed tone and Comm. Port CW key interface
There is
a windows ?gui?
interface and the requirement for RX audio feed, based round 1500 Hz , Tx audio at 1500 Hz may also be
used to drive a
audio/rf conversion ,
changes of Tx
audio tone prevent
collisions, and the software
scans for a slot of minimum noise . to place the TX carrier in.
If the CW key option is used, then the Tx frequency is
selected by the Tx master oscillator only.
Once a signal is decoded, the
decode-spot is distributed to other web-connected users, future development will link to the PSK-Reporting network .
OPERA is coded at the moment for 136 and 500 Khz and
still under
development.
As
a basic out line the system (at the moment) codes the six characters of the call sign and transmits them as a serial ?pulse? train using either conventional audio to
RF translation , or by the use of a
COM port and transistor keying cct that simply replaces the CW key
,
Reception, as the data is spread out along a
time line , decoding is completed during the final stages of the transmission , due to this ,,it is not possible to
include a receive progress monitor, however the system will track and decode multiple transmissions of
both time bases
simultaneously
Transmit times are used to denote the mode
500 Khz
2
Minuets
16
Minuets
136 Khz
8 Minuets
65
Minuets
S/N, The mode is
capable of decoding under the noise level , beyond that of
WSPR or the ROS-MF-2 system
with a maximum data loss of 33% before the decode Fails.
Opera 2 similar to
WSPR
Opera 8 6dB better than
WSPR.
Opera 65 9 dB better than Opera8,
