[Lowfer] OPERA mode improvement

[jrusgrove at comcast.net]

Haven't seen mention of this 'improvement' to OPERA mode here so thought I would make a quick post
in case others might be interested in setting up to transmit or receive.

Developed by Markus DF6NM, OPERA Deep Search improves 'standard' OPERA's weak signal threshold by
about 10 dB ... for OPERA32 that's about -50 dB SNR(r) referenced to a standard SSB bandwidth.
Basically it uses phase coherent transmission at the transmitting end (worth about 6 dB) and further
improvement from correlation of known active callsigns/grid squares. The detection bar has been set
pretty high as there have been few if any false decodes.

Unfortunately, it's not exactly 'plug and play' software. For reception it uses Spectrum Lab (with a
custom .usr file) in conjunction with the OPDS program that Markus has written. Some knowledge of
Spectrum Lab and the ability to work with .bat and .ini files is helpful. Accurate sound card
calibration is also required. The saying 'no free lunch' comes to mind.

Further informations and download at: http://df6nm.bplaced.net/opera/opds.zip .

Last night all four DK7FC transmitted sequences were received at W1VD ... see below. Reception would
have been impossible with 'standard' OPERA32 and WSPR15 - two of the best weak signal programs in
the arsenal. It likely would have even been too much for WOLF mode <gasp>.

2013-10-13 05:33:26 DF6NM   6258km 137570.047Hz   2mHz -44.5dBOp 100% 17.9dB
2013-10-13 03:33:26 DF6NM   6258km 137570.047Hz   3mHz -45.3dBOp 100% 19.1dB
2013-10-13 00:33:28 DF6NM   6258km 137570.049Hz   2mHz -42.3dBOp 100% 20.0dB
2013-10-12 23:33:26 DF6NM   6258km 137570.050Hz   1mHz -47.3dBOp 100% 17.4dB

Condx tonight not as good as last night ... grabber 1 http://www.w1vd.com/grabber.html shows the
progress.

Jay W1VD  WD2XNS  WE2XGR/2  WG2XRS/2