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Old 27-03-2012, 20:17   #31
Digger
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A 62 minutes log until QRT. High Doppler values, almost perfect CDA, but many problems with interruptions in the audio. And why not test a different DRM mode?


PS, I got an answer to my e-mail:
"Thanks for your mail. We are constantly relying on reports like yours to improve our transmission. Kindly keep sending your observations. Thanks.
A. A. AbdusSalam
Special Assistant To Director General"
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Last edited by Digger : 28-03-2012 at 15:56.
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Old 28-03-2012, 20:22   #32
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Log 1h44min. but now is conds go down to niose. From S9+10db to S5.
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Old 28-03-2012, 20:40   #33
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A mostly unattended log. I had set it to shut down at 2000 UTC. An almost perfect result, but still audio problems. The Doppler is extremely high. I'm surprised that there is audio at all under these conditions.
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Old 29-03-2012, 20:12   #34
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stable reception here in Dresden during the complete transmission. Just some problems with a neighbour AM station.
I use just a small indoor antenna close to the window. Due to the 16QAM i had not so many audio drops.
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Old 29-03-2012, 20:23   #35
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This DRM signal is for me big mystery. Doppler go up over 3Hz and give no problem for audio. Signal stringth this evning was S9+10dB=44dbuV , from start to end of transmission and no fading very stable, SNR 29dB in start and go down to 20dB after 20min . to stop.

So pleas switch over to MODE B and 16.92kbps . MONO. for test.
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Old 30-03-2012, 20:13   #36
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No diff. to evning same signal stringth S9+10dB=44dbuV, MAX SNR in start 29.14dB. and doopler up over 3Hz ?????
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Old 31-03-2012, 07:56   #37
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High doppler seems to be the same situation for RNZI if you look to the plots.
Probably we are measuring the speed of the Jetstream the signal has to pass !?

Last edited by DH5YM : 31-03-2012 at 08:00.
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Old 13-04-2012, 19:31   #38
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Good Reception results tonight (decoded audio without interruptions) on an unmodified Morphy Richards sitting on a windowsill with a PC running next to it.
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Old 13-04-2012, 21:15   #39
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High SNR, terrible audio quality partly because of the 9 kbps and that from Africa's most modern studios according to themselves. At least it withstood my 15 MHz BUZZZZ QRM that is present from time to time. Without this S7 noise blanket the result would perhaps have been even better. C'mon people, change the configuration!
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Old 17-04-2012, 07:29   #40
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High Doppler values but perfect decoding in this 90 minutes log. I don't understand why VON won't change the Mode to B and perhaps increase the Bitrate somewhat.
After all, VON claims that they have the most modern and up-to-date digital facilities in all of Africa. We could expect better audio quality under those conditions.

PS: This log is of course from Switzerland, not Stockholm!
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Last edited by Digger : 18-04-2012 at 07:16. Reason: Coordinates are wrong.
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Old 18-04-2012, 05:58   #41
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All you can say about this signal is that it is robust. The Doppler left the plot area around 1900 UTC. Doppler was 1 Hz at its lowest and peaked off-screen with 3.97 Hz at 19:19! The log was unattended. But with 9 kbps it probably sounded as bad as it used to do before.

PS: The SNR was probably even higher than shown in my log, as I forgot to set the AGC to "slow".
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Last edited by Digger : 18-04-2012 at 07:15. Reason: Changed the log as it had the wrong coordinates in it
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Old 24-04-2012, 20:57   #42
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This is awsome: 4.04 Hz Doppler measured at 1928 UTC but still good decoding. I must say, it would be nice to see another configuration, because the signal is strong enough to bring good results with, say, 14 kbps and mode B or even Mode A.
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Old 26-04-2012, 20:18   #43
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Terrible doppler, good decoding except of a period of weak signal.
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Old 26-04-2012, 20:24   #44
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Hi John and all,

Interesting about the Doppler - it was not that bad in Switzerland. At least better than other logs. If they only could do something about the configuration... The sound is pathetic.
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Old 27-04-2012, 20:10   #45
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Good results tonight.
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