Hi Domenico,
this may have been due to crossmodulation from the
receiver AGC, which is visible in the spectrogram: Whenever the strong
signals from SV3DVO and IW4DXW were present simultaneously, there were also IM-3
sidebands appearing symmetrically around their frequencies. I presume
that the the false detections are generated by the AGC reacting on
SV3DVO's keying, and impressing the inverse modulation of this
sequence (which happens to be similar to VE7BDQ) onto the other
transmission.
My recommendation would be to disable the AGC in
SpecLab (L4 blackbox), and also in the receiver.
However please set the gain such that the
noise level in the spectrogram is still above about -90 dB, which is necessary
to avoid rounding errors due to the integer data export from SpecLab to
opds. Alternatively, you can untick "use integer numbers only" in SpecLabs
"Export of FFT results" settings, providing unlimited dynamic range at the cost
of larger temporary data files.
Best 73,
Markus (DF6NM)
Sent: Sunday, November 30, 2014 10:44 AM
Subject: Re: LF: 477 khz op8 deep search in km07ks last night
!!
Good day to all,
Here also my OPDS8
correlations for signals received on MF last night:
I had one quite good
correlation of VO1NA ! Thanks Joe for your transmissions.
Can
somebody help me to identify the signal that OPDS program shows 5 times with the
call of VE7BDQ ?
IZ7SLZ JN80NU Opera-32 correlation by
DF6NM
date time
call distance frequency bandwidth snr
correlation
2014-11-30 08:00:42 SV3DVO 489km
478494.556Hz 40mHz -36.5dBOp 72% 19.6dB
2014-11-30 07:35:45
SV3DVO 489km 478494.589Hz 57mHz -35.7dBOp 84%
20.4dB
2014-11-30 07:10:50 SV3DVO 489km 478494.587Hz 116mHz
-37.6dBOp 95% 20.3dB
2014-11-30 06:45:53 SV3DVO 489km
478494.593Hz 69mHz -32.4dBOp 82% 20.7dB
2014-11-30 06:20:58
SV3DVO 489km 478494.593Hz 48mHz -26.5dBOp 89%
21.7dB
2014-11-30 05:56:01 SV3DVO 489km 478494.593Hz 23mHz
-30.5dBOp 77% 19.7dB
2014-11-30 05:30:56 SV3DVO 489km
478494.583Hz 42mHz -25.0dBOp 89% 21.9dB
2014-11-30 05:06:02
SV3DVO 489km 478494.596Hz 19mHz -20.4dBOp 100%
20.9dB
2014-11-30 04:41:00 SV3DVO 489km 478494.579Hz 69mHz
-25.6dBOp 93% 20.5dB
2014-11-30 04:16:03 SV3DVO 489km
478494.591Hz 50mHz -19.3dBOp 80% 21.5dB
2014-11-30 03:51:08
SV3DVO 489km 478494.606Hz 55mHz -19.0dBOp 91%
21.7dB
2014-11-30 03:26:11 SV3DVO 489km 478494.596Hz 116mHz
-22.5dBOp 78% 21.6dB
2014-11-30 03:01:16 SV3DVO 489km
478494.600Hz 63mHz -19.1dBOp 93% 21.5dB
2014-11-30 02:45:35
VO1NA 5445km 478478.592Hz 477mHz -33.7dBOp 72% 16.3dB
:-)
2014-11-30 02:43:48
VE7BDQ 9286km 478500.746Hz 614mHz -32.5dBOp 99% 15.7dB
:-\
2014-11-30 02:37:27
IW4DXW 610km 478500.504Hz 687mHz -99.9dBOp 87%
20.1dB
2014-11-30 02:36:19 SV3DVO 489km 478494.612Hz 38mHz
-19.8dBOp 77% 20.7dB
2014-11-30 02:12:30 IW4DXW 610km
478500.538Hz 99mHz -30.1dBOp 59% 20.2dB
2014-11-30 02:11:24
SV3DVO 489km 478494.661Hz 21mHz -20.4dBOp 94%
21.0dB
2014-11-30 01:56:08 PA3ABK 1543km 478526.709Hz 563mHz -18.4dBOp
100% 20.8dB
2014-11-30 01:53:56 VE7BDQ 9286km 478500.278Hz 566mHz
-36.8dBOp 100% 15.6dB
2014-11-30 01:47:35 IW4DXW 610km
478500.502Hz 668mHz -21.4dBOp 97% 21.1dB
2014-11-30 01:36:40
G0NBD 2056km 478528.494Hz 435mHz -18.3dBOp 48%
15.7dB
2014-11-30 00:58:10 SV3DVO 489km 478494.665Hz
13mHz -21.1dBOp 100% 22.0dB
2014-11-30 00:49:31 SV3DVO 489km
478494.661Hz 15mHz -19.3dBOp 86% 22.0dB
2014-11-30 00:43:52
G3XDV 1796km 478463.135Hz 13mHz -37.5dBOp 100%
17.9dB
2014-11-30 00:39:54 SV3DVO 489km 478494.671Hz 11mHz
-19.8dBOp 100% 21.5dB
2014-11-30 00:31:25 SV3DVO 489km
478494.680Hz 13mHz -18.1dBOp 94% 21.9dB
2014-11-30 00:24:29
G6AVK 1736km 478501.659Hz 15mHz -40.4dBOp 83%
17.0dB
2014-11-30 00:22:15 SV3DVO 489km 478494.698Hz 11mHz
-18.7dBOp 100% 21.7dB
2014-11-30 00:13:42 SV3DVO 489km
478494.703Hz 15mHz -18.4dBOp 84% 22.1dB
2014-11-30 00:04:26
IW4DXW 610km 478500.532Hz 13mHz -18.7dBOp 58%
17.7dB
2014-11-30 00:04:26 SV3DVO 489km 478494.696Hz 15mHz
-21.0dBOp 100% 21.0dB
2014-11-29 23:58:40 G3XDV 1796km
478463.169Hz 13mHz -34.7dBOp 97% 18.7dB
2014-11-29 23:55:04
SV3DVO 489km 478494.682Hz 34mHz -20.2dBOp 92%
21.6dB
2014-11-29 23:49:54 VE7BDQ 9286km 478500.532Hz 15mHz
-31.3dBOp 100% 15.6dB
2014-11-29 23:44:15 SV3DVO 489km
478494.686Hz 15mHz -19.7dBOp 80% 21.0dB
2014-11-29 23:43:33
IW4DXW 610km 478500.519Hz 404mHz -36.3dBOp 86%
20.7dB
2014-11-29 23:34:56 SV3DVO 489km 478494.675Hz 42mHz
-22.7dBOp 89% 21.4dB
2014-11-29 23:20:00 SV3DVO 489km
478494.669Hz 40mHz -21.6dBOp 100% 21.7dB
2014-11-29 23:11:26
SV3DVO 489km 478494.644Hz 40mHz -21.5dBOp 87%
21.7dB
2014-11-29 22:58:09 SV3DVO 489km 478494.629Hz 59mHz
-18.3dBOp 100% 21.9dB
2014-11-29 22:55:57 VE7BDQ 9286km
478500.673Hz 641mHz -34.1dBOp 100% 15.9dB
2014-11-29 22:49:36
IW4DXW 610km 478500.471Hz 57mHz -19.2dBOp 97%
17.8dB
2014-11-29 22:48:17 SV3DVO 489km 478494.637Hz 19mHz
-15.8dBOp 100% 22.1dB
2014-11-29 22:38:56 SV3DVO 489km
478494.633Hz 32mHz -17.0dBOp 89% 21.8dB
2014-11-29 22:28:55
SV3DVO 489km 478494.629Hz 32mHz -16.1dBOp 88%
22.0dB
2014-11-29 22:21:54 VE7BDQ 9286km 478500.713Hz 574mHz -34.2dBOp
100% 16.0dB
2014-11-29 22:15:33 IW4DXW 610km 478500.437Hz 633mHz
-31.2dBOp 96% 20.8dB
2014-11-29 22:01:18 PA3ABK 1543km
478526.562Hz 454mHz -24.0dBOp 89% 20.6dB
2014-11-29 21:47:59
VE7BDQ 9286km 478500.444Hz 51mHz -31.5dBOp 100% 15.8dB
2014-11-29
21:45:59 SV3DVO 489km 478494.669Hz 21mHz -21.4dBOp 100%
20.3dB
2014-11-29 21:41:38 IW4DXW 610km 478500.383Hz 723mHz
-31.3dBOp 85% 21.3dB
2014-11-29 21:25:59 SV3DVO 489km
478494.608Hz 15mHz -18.3dBOp 100% 21.9dB
2014-11-29 21:16:33
SV3DVO 489km 478494.596Hz 65mHz -30.0dBOp 98%
21.7dB
2014-11-29 21:08:17 IW4DXW 610km 478500.368Hz 568mHz
-20.6dBOp 77% 20.8dB
2014-11-29 20:54:33 SV3DVO 489km
478494.621Hz 19mHz -19.9dBOp 98% 21.6dB
2014-11-29 20:54:04
PA3ABK 1543km 478501.566Hz 549mHz -99.9dBOp 78% 18.3dB
2014-11-29
20:44:14 SV3DVO 489km 478494.638Hz 21mHz -18.3dBOp 100%
21.7dB
2014-11-29 20:41:21 VE7BDQ 9286km 478500.380Hz 34mHz
-23.2dBOp 94% 15.6dB
2014-11-29 20:38:28 G3XDV
1796km 478484.392Hz 15mHz -37.1dBOp 99% 17.4dB
2014-11-29
20:35:00 IW4DXW 610km 478500.164Hz 711mHz -30.5dBOp 68%
20.0dB
2014-11-29 20:01:38 IW4DXW 610km 478500.359Hz 687mHz
-20.1dBOp 85% 20.4dB
2014-11-29 19:39:37 G0NBD 2056km
478525.299Hz 372mHz -21.7dBOp 61% 16.7dB
2014-11-29 19:28:20
IW4DXW 610km 478500.160Hz 694mHz -20.9dBOp 76%
21.0dB
73 and good Sunday
Domenico/ iz7slz
JN80NU Putignano -
Apulia (Italy)
