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Old 28-02-2013, 21:11   #31
Digger
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At the beginning of this log the signal was about 37 dBuV. A weak period around 0650 caused the overall result to worsen.

Max. SNR was 30.0 dB just before the end of the log and 95.36% decoded audio. I logged with Dream's Time Sync Tracking set to "First Peak" because the CIR is very diffuse with many peaks.
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Old 01-03-2013, 02:23   #32
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Quote:
Originally Posted by Digger
At the beginning of this log the signal was about 37 dBuV. A weak period around 0650 caused the overall result to worsen.

That is what VOACAP predicts. The signal should be stronger at 0500 and then it goes down over the next two hours as the strong signal area contracts (I had to squint to see where Stockholm is located in the two low resolution files that I submitted earlier).
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Old 01-03-2013, 09:06   #33
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It is true that the signal is stronger at the beginning of my logs. So far I haven't been up that early to see the start, but I'll run a scheduled event and see what it looks like.

99.64% decoded audio during the last hour this morning. Max SNR was 30.36 dB at 0645 UTC.
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Old 01-03-2013, 11:52   #34
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BBC 3955 KHz reception near Atlanta, Georgia, USA

Hi Terje,

Thank you for the update. It will be interesting to see your signal strength report.

The overnight reception here was 0.77% decoded audio, 14.44 dB max SNR.

VOACAP does not show any useful signal coverage at my location, so any decoding is just luck.

Some fellow hams have complained that the model sometimes "under predicts" for the lower frequenies (3.5 MHz and below).
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File Type: png 3955-130301-0500-0658-AF4MP.png (37.0 KB, 697 views)
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Old 01-03-2013, 12:09   #35
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Hi Zyg,

I logged the last hour this morning, and the signal was rather stable with slow Fading. The signal varied from +30 to +37 dBuV. Log follows later (I'm on a different PC just now).

Yes, I'm just on the 30 dBuV line.
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File Type: png 3955-130301-0603-0659-Terje@SE.png (46.3 KB, 646 views)
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Last edited by Digger : 01-03-2013 at 16:25.
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Old 01-03-2013, 13:52   #36
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Hi Terje,

Thanks for the info!

Attached is the VOCAP plot for 0700utc the time at which the 3955 kHz BBC broadcast finishes.

The plot is redrawn with the Woofferton transmitter antenna at the center.

It looks like Stockholm (at 0700utc) is on the 30 dBu line.

It is interesting that the signal from the back end of the beam extends quite a bit into the north Atlantic. Water certainly does help!
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File Type: png Woofferton TX 3955 kHz 0700utc March 2013.PNG (76.5 KB, 613 views)
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Old 02-03-2013, 06:14   #37
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Forgot to set the Event Timer in the Plotter. Better luck tomorrow? Just a short log with a n RF signal that is getting weaker during the last 13 minutes of the transmission.
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File Type: png 3955-130302-0645-0659-Terje@SE.png (40.7 KB, 731 views)
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Old 02-03-2013, 06:31   #38
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Newstar with internal whip

Very poor start here in Bath UK, no audio, then improved in last hr of TX to stable audio, I notice the DRM jingle was played at the end of the TX
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Old 02-03-2013, 14:49   #39
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BBC 3955 KHz reception near Atlanta, Georgia, USA

The overnight reception report - 3.98% decoded audio, 15.90 dB max SNR.
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Old 03-03-2013, 05:45   #40
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Newstar and Internal Whip

Nothing at all till 0630 today, then good reception , local interference ?
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Old 03-03-2013, 05:57   #41
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Quote:
Originally Posted by ianf
Nothing at all till 0630 today, then good reception , local interference ?

Probably (~ 125 miles), but I'm currently receiving STRONG noise on the 25 meter band which doesn't look promising for receiving RNZI on 11675 kHz this morning, but I will try ... Even the 49 meter band is considerably worse than normal. Current difficulties are probably related to solar and geomagnetic disturbances as well....

Last edited by tpreitzel : 03-03-2013 at 19:46.
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Old 03-03-2013, 06:54   #42
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A stable signal at the beginning when I started the log, but I did not check the S-meter from 0525-0540 when there were some decoding problems. The log was unattended until 0615.
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File Type: png 3955-130303-0500-0658-Terje@SE.png (47.5 KB, 671 views)
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Old 03-03-2013, 12:06   #43
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BBC 3955 KHz reception near Atlanta, Georgia, USA

The overnight reception report - no decoded audio, 9.97 dB max SNR.
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Old 03-03-2013, 16:28   #44
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Terje,

Thank you again for including the signal strength. It would be interesting to see the lowest dBuV reading that still decodes audio at 100%.
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Old 04-03-2013, 06:44   #45
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Newstar and internal whip

Again nothing till 0622, dawn, then good reception here in Bath UK
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