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dk8cb
16-08-2005, 19:24
Hi,

not so good over here mainly due to fading.

Roland

dk8cb
16-08-2005, 19:37
Hi,

during the last few minutes of this increased-bandwidth transmission, I tuned my receiver to the adjacent channel, 9 kHz higher. The station transmitting on 1305 kHz calls itself "Pure FM" and belongs to RTBF from Belgium, not even far away from Orfordness. I have verified the origin of this programme by listening to the live stream on the internet.

Listen to the attached MP3 recording. For the first part, I used an IF bandwidth of about 8 kHz, reception was quite ok then, but as soon as I increased the receiver's bandwidth to 9 kHz, interference became very strong and made reception in double sideband AM mode quite difficult.

Roland

simone
16-08-2005, 21:01
Hi James,
I was surprised that you were using mode B tonight with the 10 kHz signal. The past days I always got 100% at least from 1830, but today a few dropouts although the SNR was higher :(
(BTW the version of DreaM I was using is not supporting UEP)
No problems due to the 10 kHz wide signal, no interference from adjacent channels.
Audio bitrate was nearly the same, so why use mode B which would require a higher SNR on a transmission where co-channel interferers and fading always cause problems?
It will be interesting to see how results on the night transmission compare to the lately excellent results.
But nice to see some experiments on DRM transmissions again :)
73, Simone

dk8cb
16-08-2005, 22:52
Hi,

unfortunately, the switch to the other mode and bitrate seems to have brought back unwanted effects that were thought to have been overcome.
I noticed an interruption shortly after the start of the late night transmission at 21:08 UTC and I also noticed a repetition which sounded like "the Israeli army geared up geared up ...".
See the attached cut-out from the waterfall plot which shows the interrruption.

Roland

dk8cb
17-08-2005, 00:06
Hi,

mode B with its higher SNR requirements seems to have lessened the overall decoding success.
See attached screenshot which includes results from both DRMSWR and Dream.

Roland

simone
17-08-2005, 06:09
Hi all,
I also noticed the interruption at 2108, maybe just a coincidence and not related to yesterdays changes. But maybe these changes also caused the problems on the Russian transmission?
As usual on UEP transmissions the audio light on the FhG decoder often was red but audio was OK for listening.
The old configuration worked a lot better, hope it was only a test for one night with this configuration.

73, Simone

jbriggs
17-08-2005, 08:22
The main aim of the tests is to see if we can have the same DRM signal on HF & MF, this means we are operating an MFN and therefore receivers will have no trouble to switch between Orfordness and the HF transmission. Thanks for the comments so far. Maybe Mode A on HF is possible, we will look into this.
James

simone
17-08-2005, 19:30
Hi all,
better results back in mode A and with increased bitrate this evening :)
Again no problems with adjacent channels due to the 10 kHz bandwidth.
If the conditions of the corresponding HF transmission(s) would allow for mode A this would be a great configuration also for this MF transmission. Otherwise an MFN of MF and HF transmissions would always be a (bad) compromise.
@James: Thanks for explaining the purpose of these 10 kHz tests.
The attachment shows the comparison with yesterdays results.
73, Simone

FritzWue
17-08-2005, 20:07
Good audio, now we still need stereo.:)
The spanish interference started very early from 17:20 UTC this evening, so I switched to the shielded loop at 18:20 UTC and tried different positions for some time. That caused the two dropouts.

FritzWue
17-08-2005, 20:38
Tonight I also recorded the identification of the spanish interferer on 1296kHz when Orfordness was off between 19:15 and 19:30 UTC.
It is indeed Cadena COPE Valencia:
http://www.cope.es/paginas/emisoras.asp?p=1&id=33

I've zipped the short mp3 64kbps file:

simone
17-08-2005, 21:39
Hi James and all,
this evening interruptions occured again at the beginning of the night transmission, I noticed them at 2109 and twice at 2116
73, Simone

dk8cb
18-08-2005, 00:13
Hi,

here is my report, logged partly unattended.

Not very good.

Roland

dk8cb
18-08-2005, 00:16
Hi,

my unattended log, so no comment on interruptions or repetitions.

Roland

FritzWue
18-08-2005, 05:02
Good audio at start, then unattended log with dropouts:

simone
18-08-2005, 06:22
Hi all,
as I already mentioned above, the cold start problem occured again last night, also the 4 dropouts between 2215- 2250 seem to be Tx related. Besides this the new configuration works better and also gives great audio quality.
73, Simone

jbriggs
18-08-2005, 09:03
Hi Simone, thanks for the dropout information, I will e mail the transmitting site as yesterday we configured the DT700 monitoring Rx to record an IQ signal of the Tx output.
James

simone
18-08-2005, 20:15
Hi all,
good results from Orfordness at the end of the evening transmission, using the same configuration as yesterday, see attachment
73, Simone

dk8cb
18-08-2005, 20:25
Hi,

not so good over here.
Fading and dropouts.

Roland

dk8cb
18-08-2005, 23:52
Hi,

a strong signal with only a few problematic moments.

Roland

FritzWue
19-08-2005, 05:03
Unattended log of the late night transmission.
Don't know what caused the dropouts.

simone
19-08-2005, 05:56
Hi James, all,
pretty good conditions last night, the only dropouts (at 2150 & 2250) in my results can also be seen in the other reports and they also occured on my other receiver using the loop antenna, maybe it is worth investigating.
No "cold start" problem last night.
73, Simone

dk8cb
19-08-2005, 19:19
Hi,

today, signal strength increased only slowly to a level, where listening became comfortable.
I noticed a short interruption in the DRM stream at 18:43 UTC.

The dropout at 19:04 UTC was of my own making. ;-)

Roland

simone
19-08-2005, 20:24
Hi all,
only an unattended log, but I guess bad results were caused by the thunderstorms which also caused some trouble around here.
73, Simone

dk8cb
20-08-2005, 10:55
Hi,

not a bad result. The first dropout was caused by fading. I cannot comment on the others, since the receiver was logging unattendedly.

Roland

simone
20-08-2005, 11:06
Hi all,
much better conditions than in the evening, perfect decoding except two of the new kind of dropouts that occur (with both decoders) since the BBC are using the 10 kHz bandwidth, looked to me like a datastream problem, cauisng a loss of sync.
73, Simone

simone
20-08-2005, 17:10
... and here is a more detailed picture of the dropout at 2125, just a loss of sync (at-3.5min)
73, Simone

simone
20-08-2005, 19:50
Hi all,
a weak signal on the evening transmission when I started, got stronger in the last minutes. Some normal dropouts due to the weak signal and interferences.
73, Simone

simone
21-08-2005, 05:11
Hi all,
good results with a few minor dropouts, the dip at 2207 was again the new sync loss problem, see attachment
73, Simone

FritzWue
21-08-2005, 05:54
Good results here too except this single dropout Simone already mentioned:

dk8cb
21-08-2005, 13:33
Hi,

strong interference from south-eastern Europe and quite a number of moments with fading and dropouts.

Roland

dk8cb
21-08-2005, 19:31
Not a good result. Strong co-channel signals together with Orfordness' signal fading caused many dropouts.

Roland

FritzWue
21-08-2005, 19:44
Upcoming interference during the evening transmission after about 17:30 UTC.
I switched from the wire antenna to the loop at 18:45 UTC.
The difference is easy to see:

simone
21-08-2005, 20:43
Hi all,
bad condtions this evening causing two major dropouts, see attachment
73, Simone

FritzWue
22-08-2005, 04:59
Good reception here of the late night transmission except one dropout:

simone
22-08-2005, 06:20
Hi James, all,
I did not watch it last night, but the dropouts look again like they were caused by the new sync loss problem.
73, Simone

dk8cb
22-08-2005, 09:17
Hi,

some dropouts were strange: The waterfall plot did not show anything that could have caused them, looks as if they were already coded into the transmitted stream.

Roland

simone
22-08-2005, 15:09
Originally posted by dk8cb

some dropouts were strange: ...

Hi Roland,
whenever I watched it, there was a complete loss of sync, not only some dropouts, but no obvious reason for this to happen that I could see.
I wonder if last week there were some more changes at BBC than just switching to 10 kHz bandwidth.
Maybe the BBC should go back to 9 kHz to see if the problem is still there.
73, Simone

dk8cb
22-08-2005, 18:08
Originally posted by simone
Maybe the BBC should go back to 9 kHz to see if the problem is still there.


Mode A using 9 kHz bandwidth had recently worked flawlessly (well, except from interference and propagation influences). I notice, that with IFA approaching, the number of experiments is increasing.
I still hope that this will not result in transmissions with a lot of technical problems or even complete failure during IFA. We have seen such problems during other events.
HF also seems to have more problems recently.
There is a saying "Never change a running system". ;)

I don't know whether yesterday's dropouts were accompanied by total sync loss since I listened from another room via an open door and when I came back to look at the screen a few seconds after a dropout, I could not see anything from which to determine its cause.

Roland

FritzWue
22-08-2005, 19:22
Only the last ten minutes of the evening transmission, good signal on the loop, strong signal from Spain too.

simone
22-08-2005, 21:00
Hi all,
quite good in the last half hour of the evening transmission.
@Roland: I think there is nothing wrong with doing experiments at this time, before there are millions of listeners, as this also means investigating and identifying problems that could occur later on regular transmissions.
73, Simone

dk8cb
22-08-2005, 22:17
Originally posted by simone
I think there is nothing wrong with doing experiments at this time, before there are millions of listeners...


Of course! But one should not do it during IFA. I remember experiments during last year's exhibition in Amsterdam which resulted in terrible data stream problems.
Such is not the proper method to convince people at an exhibition that DRM is a mature technology.

Roland

simone
23-08-2005, 06:14
Hi all,
it looks like the new sync loss problem occured again twice last night, still no ideas, see attachment
73, Simone

FritzWue
23-08-2005, 06:16
Late night transmission, two dropouts, otherwise good:

dk8cb
23-08-2005, 09:15
Hi,

last night's report. Signal became unusually strong during the last hour.

The first part of Outlook broadcast before the news, was an old edition that had already been broadcast last week. Someone must have put a wrong file on the air. Also, text messages during Outlook were completely wrong and showed the presenters' names as Frederic Dove and Heather Payton when it should have been Russel Fuller instead.

Roland

simone
23-08-2005, 20:21
Hi all,
stronger signal than the past days, good results, see attachment

Originally posted by dk8cb
I remember experiments during last year's exhibition in Amsterdam which resulted in terrible data stream problems.
Such is not the proper method to convince people at an exhibition that DRM is a mature technology.


@Roland: There were no datastreamproblems during IBC last year, demonstrations of the additional services worked fine!

73, Simone

dk8cb
23-08-2005, 20:49
@ Simone

So my memory must have fooled me. :confused: However I still think that one of last or this year's shows was accompanied by data stream problems but which show was it?

Roland

FritzWue
24-08-2005, 06:13
High snr during the late night transmission:

simone
24-08-2005, 06:23
Hi all,
the problem occured again once last night (at 2308). I still think it is related to the changes last week, as we never had this kind of sync loss before and it has happened regularly each night for a week now.
73, Simone

dk8cb
24-08-2005, 08:11
Quite good with two fading incidents when interference took over. I also noticed the dropout at 23:08 UTC.

Roland

simone
24-08-2005, 19:55
Hi all,
good results this evening, still using 10 kHz bandwidth :(, but I am not sure what caused the dropout, see attachment
73, Simone

FritzWue
24-08-2005, 20:35
Little problems tonight with the evening transmission.
When some dropout occured at 18:15UTC I found that they were coming from the Balkans, so I turned my loop's minimum to there, all ok.
A 18:45UTC again some dropouts, but now the interference was coming from Spain, so had to rotate the loop again. There were less variations in SNR from then on.

dk8cb
24-08-2005, 22:51
Originally posted by FritzWue
When some dropout occured at 18:15UTC I found that they were coming from the Balkans, so I turned my loop's minimum to there, all ok.

Hi Fritz,

that is my problem: If you draw a line from Orfordness to the Balkans where the other transmitters are, then I am almost sitting right on this line. No way to null the signals from the southeast. No problems with Valencia though, its direction is at a right angle to Orfordness.

Roland

simone
25-08-2005, 06:05
Hi all,
good results last night, I did not notice the sync loss problem, has it been solved?
73, Simone

dk8cb
25-08-2005, 08:26
Hi,

no sync loss problem noticed over here as well during my logging period. Reception was rather good but I also did not have any local interference. Now with autumn approaching, signal strength seems to be increasing.

Roland

FritzWue
25-08-2005, 11:36
Very good results during the late night transmission, loop's minimum to Spain again. ;)

FritzWue
25-08-2005, 18:38
No fun this evening, thunderstorms again:

simone
25-08-2005, 19:48
Hi all,
signal was not very strong this evening, some dropouts, see attachment
73, Simone

dk8cb
26-08-2005, 00:05
Hi,

autumn conditions seem to have arrived. Signal was very strong, similar to how it was in spring. Superb reception.

Note the SNR improvement shortly after 23:00 UTC, whatever its reason...

Roland

simone
26-08-2005, 05:55
Hi all,
strong signal, perfect results last night, see attachment
73, Simone

dk8cb
26-08-2005, 19:39
Hi,

I have seen much better results. Signal faded heavily and interference was rather strong.

Roland

simone
26-08-2005, 20:17
Hi all,
only a short report, quite good except the sync loss problem seems to be back again causing the only dip in the graph.
73, Simone

Andreas
26-08-2005, 22:42
Hi !

Normally I would be satisfied with this log, when a (for me) record breaking SNR of 29,8 dB was achieved with but my small magnetic loop depicted!

However there are some interruptions most probably caused by the Tx. And also fading occured.

What makes me sceptic: Medium wave is very sensitive to local noise. How will they cope with it in the future? When using a built in ferrite rod for MW reception you will experience, same as I do with my indoor antenna, that even switching a light on or off may cause a dropout , which is more noticeable as the short crackle you hear on analogue AM !

Good night and good DX !

Andreas

simone
27-08-2005, 06:03
Hi all,
I guess it would be a 100% results if it were not for this sync loss problem, see attachment
73, Simone

carknue
27-08-2005, 08:06
Very bad results. Spanish stations was too strong.

dk8cb
27-08-2005, 09:24
Hi,

before transmission started, I could not hear the spanish station with the loop directed properly but the signals from the Balkans were there.
There was only a small number of dropouts that were caused by fading, the others seemed to be caused by the stream itself.

As always, somebody went off the air shortly after 23:00 UTC.

Roland

dk8cb
27-08-2005, 19:26
Hi,

not so bad after signal had gained strength.
The plot starts at about local (astronomical) sunset.

Roland

simone
27-08-2005, 19:56
Hi all,
the sync loss problem occured twice at 1823, I think also at 1904, the other dropout was my fault, see attachment
73, Simone

simone
28-08-2005, 05:12
Hi all,
perfect last night, see attachment
73, Simone

FritzWue
28-08-2005, 07:25
Perfect here too:

carknue
28-08-2005, 08:13
Far away from being perfect here. Reason: Very strong spanish AM station.

dk8cb
28-08-2005, 13:10
Hi,

the deep dips were caused by fading and interference from the Balkans. The spanish station could be nulled perfectly.

Roland

dk8cb
28-08-2005, 19:29
A few dropouts.

Roland

simone
28-08-2005, 19:41
Hi all,
perfect from 1830, see attachment
73, Simone

simone
28-08-2005, 19:50
... and besides the AM interferers that get mentioned a lot on this thread, I always have another interference, see attachment.
In this case the SNR measurement in DREaM and DRMSWR are of no use. As I mentioned before on other threads, the MER is a lot more important. I even get good audio decoding at 0 dB SNR indicated by the software decoders on this transmission. But as soon as the signal from Orfordness gets stronger this interference does not influence the SNR results a lot.
73, Simone

simone
28-08-2005, 21:29
Hi James, all,
after several days the "cold start problem" was back tonight, I noticed it at the beginning of the night transmission about 2113 UTC.
73, Simone

dk8cb
28-08-2005, 22:36
Originally posted by simone
... and besides the AM interferers that get mentioned a lot on this thread, I always have another interference, see attachment.

Hi Simone,

does this interference occur on all possible RX-PC combinations or only on certain ones?

My MER plot is attached, I took the screenshot during a moment of selective fading which affected carriers in the left part of the plot. Over here, I cannot observe the signals that can be seen in your plot.
But also, no one else seems to observe the SNR improvement after about 23 h UTC that I always get.

Roland

dk8cb
29-08-2005, 06:05
There was quite a bit of fading last night.

Roland

simone
29-08-2005, 06:31
Hi all,
quite good last night, the first dip at 2113 related to the cold start problem, the other at 2204 seems to be again the sync loss problem, see attachment
73, Simone

dk8cb
29-08-2005, 19:23
Hi,

today, reception was only good during the last 10 minutes.

Roland

simone
29-08-2005, 19:40
Hi all,
perfect decoding from 1830 like most days, see attachment
73, Simone

simone
30-08-2005, 06:31
Hi all,
great results last nights, the two dips were Tx problems, see attachment
73, Simone

dk8cb
30-08-2005, 07:50
A bit of fading and TX problems as well.

Roland

Baldo34
30-08-2005, 12:12
From September 1st 1296 kHz will run from 06:00-24:00 each day.
73, Klaus

FritzWue
30-08-2005, 12:14
Very good!!! :cool:

simone
30-08-2005, 21:19
Hi all,
good results this evening, I stopped recording the logfile as usual at 1915, but later realized that the transmission continued, so already today no break for the analogue transmission :)!
73, Simone

dk8cb
30-08-2005, 22:06
Hi,

I don't know, if this went as was originally planned but transmission from Orfordness ended earlier than usual at 22:00 UTC.

But listening can go on as Kvitsoy continues with a big signal on 7465 kHz. ;)

Here is my report. Strong signal but also a few fade-outs.

Roland

FritzWue
31-08-2005, 06:46
"From September 1st 1296 kHz will run from 06:00-24:00 each day."

It's on today already.

dk8cb
31-08-2005, 10:06
Originally posted by FritzWue
"From September 1st 1296 kHz will run from 06:00-24:00 each day."

I have just received information, that the schedule has to be corrected to:
0600 CET/CEST to midnight CET/CEST, so the times given above are not to be taken as UTC!

So, with regard to UTC, transmission will start and end an hour earlier after summer time has ended.

Roland

jbriggs
31-08-2005, 10:53
Roland thanks for posting the information, yes the plan is to run 1296 kHz from 06:00 CET/CEST right up to midnight - forever. But until the end of October the start time will be 08:00 CEST because RNW use the frequency for an analouge broadcast until 08:00.
I don't know how long the 10 kHz test will continue.
It would be great to have some daytime reception reports from Holland/Belgium.
James

simone
31-08-2005, 16:12
Hi all,
after a PC problem last night I finally found last night´s logfile :)
Good results but also the Tx problem occured again. I still think this never happened with the 9 kHz bandwidth, so why not go back to 9 kHz for 2-3 nights as a test, or any ideas what is causing this new problem?
Btw the new schedule without the break for the analogue transmission in the evening is great :)!
73, Simone

FritzWue
31-08-2005, 16:29
Here the first daytime log from the dutch border close to Enschede.
Most time I let it run unattended, so I only was there when the dropout at 10:22UTC occured. That was a modulation problem because there was no visible interference and the stream was not interrupted in the waterfall diagram.
When I stopped the log I noticed that the SDC CRC display was flashing between yellow and green in second intervals, and it is still doing it now as I'm writing this after a reboot and restart of DREAM.
P.S.: The transmitted time is 7 seconds too early with me.

simone
31-08-2005, 17:59
Hi Fritz,
it seems the flashing of the SDC light is related to broadcasting AF information on this transmission, this means the SDC contains invalid data.
73, Simone

dk8cb
31-08-2005, 22:03
Hi,

I just listened for 45 minutes and reception was quite good with a few fade-outs and a flashing SDC indicator.

I forgot to switch logging on, sorry.

Roland

simone
01-09-2005, 06:21
Hi all,
my first 4 hour log with the new schedule, strong signal from 1830, for the first time I noticed that AF information was transmitted but as mentioned above the SDC data problem was there all the time, also the sync loss problem occured a few times.
73, Simone

simone
01-09-2005, 22:13
Hi all,
some problems at the beginning due to thunderstorms, still the SDC data problem, also the sync loss problem occured again several times.
73, Simone

Jos
02-09-2005, 22:49
Hi all,

Results for today (only 1 hour transmission !)

Kind regards.

Jos.

df9rb
03-09-2005, 07:07
Hi all,

at 6:40 the signal went down.

Bernd, DF9RB

FritzWue
03-09-2005, 10:53
Quite a new experience doing the saturday morning shopping tour through town with Emma B in hifi on mediumwave. :D

Jos
03-09-2005, 13:48
Hi all,

Results for today.

Kind regards.

Jos.

df9rb
04-09-2005, 07:21
Hi all,

today at 6:45 no more propagation to South East Germany (near the Czech boarder)

Bernd, DF9RB

simone
04-09-2005, 09:18
Hi all,
signal was already strong enough from 19:00 yesterday evening, local sunset is 20:05, good results, the dips in the graph are still the Tx problem.
73, Simone

simone
06-09-2005, 06:16
Hi all,
good results last night, also the SDC problem seems to be solved :)
73, Simone

simone
07-09-2005, 06:15
Hi all,
bad results last night, only a weak signal from Orfordness most of the time, again the improvement around susnset (marker) is obvious in the results
73, Simone

dk8cb
07-09-2005, 09:49
Hi,

signal during the last hour was good but my neighbour was at home and had his low-voltage lighting on, the pulse noise emitted by it reduces my headroom for interference.
A few dropouts during fading as a result.

Roland

simone
08-09-2005, 08:08
Hi all,
like on SW, there was a period when the signal was extremely weak yesterday evening, good results from 1830, 3 dips in the graph caused by the sync loss problem.
73, Simone

FritzWue
09-09-2005, 05:56
Good reception here after the sun's flare last night, back on 19.80kbps now, probably preparing for mm content mentioned in the label.
:confused:

FritzWue
09-09-2005, 09:39
A lot of static noise in the atmosphere this morning.
Situation getting better over the day.
Probably problems again tonight?

carknue
09-09-2005, 22:05
Not really a pleasure to listen to.

dk8cb
10-09-2005, 10:08
Hi,

rather bad last night.

Roland

dk8cb
10-09-2005, 22:14
Hi,

I have seen days with better reception but one could still listen.
Local and remote interference was bad and signal was not strong as well.

Roland

dk8cb
11-09-2005, 22:39
Hi,

unfortunately, the impulse response did not look good during the most important part of the broadcast of the last night of the PROMS. :(
Perhaps today's solar activity should be blamed ...

Roland

dk8cb
12-09-2005, 23:28
Hi,

not so good tonight. Looks like winter conditions are approaching.

Roland

dk8cb
13-09-2005, 22:16
Hi,

not a good signal at the beginning of my logging period but quite strong later.

Roland

dk8cb
14-09-2005, 22:53
Much better than I had expected after today's ionospheric problems.

Roland

Sixten
15-09-2005, 04:55
Hi all.

This is my firts DRM reciption on MW, signal was very good but very slow QSB.

So here is my report over 50min.

FritzWue
15-09-2005, 12:37
48712 Gescher - A31 - A30 - 49479 Ibbenbueren

Mobile DRM on mediumwave is very susceptible to man made noise from car ignition, high voltage power lines, electrical fences, overhead cables, etc., underpassing bridges is bad too....
Some dropouts were caused by my notebook's power management when switching off display or disk.

simone
15-09-2005, 16:33
Hi all,
some results from yesterday in the Netherlands, mobile results at the beginning between Amsterdam and Hilversum using the whip antenna (which of course is not really an antenna for MW), the 3 dips in the audio graph look like the "sync loss problem" occured again, see attachment
Btw also great results last Sunday afternoon with stable 28 dB SNR when driving on Flevoland (sorry no logfile)
73, Simone

carknue
15-09-2005, 22:23
Not too bad. I think some of the dips were TX breaks.

simone
16-09-2005, 06:00
Hi all,
pretty good results from 1740, except Tx related dropouts, see attachment
73, Simone

simone
17-09-2005, 06:27
Hi all,
quite good after sunset, (sync loss problem at 2011), see attachment
73, Simone

dk8cb
17-09-2005, 10:37
Conditions were quite strange last night and produced a lot of fading.

Roland

simone
18-09-2005, 07:26
Hi all,
a few dropouts last night, some were Tx related (like the one at 2148), see attachment
73, Simone

dk8cb
18-09-2005, 13:24
Hi,

fading and on-channel interference caused quite a number of dropouts last night.

Roland

FritzWue
18-09-2005, 14:42
Good daytime results within the target area.
The dropouts were transmitter problems.
At 09:44UTC the modulation was gone, only a full carrier left,
and at 11:49UTC DRM modulation was still there, but no audio.

simone
18-09-2005, 14:51
Hi Fritz,
it seems the dropouts occured during the times when the configuration on SW was changed, so that´s probably related.
73, Simone

simone
19-09-2005, 06:34
Hi all,
good conditions last night, not sure what caused the dropouts
What about reducing the bitrate for the EPG also on this transmission?
73, Simone

jbriggs
19-09-2005, 11:02
What about reducing the bitrate for the EPG also on this transmission?

Yes this was the intention of the BBC to reduce the bitrate of the EPG now IBC is over.

dk8cb
19-09-2005, 22:07
A rather bad result today.

Roland

simone
20-09-2005, 05:16
Hi all,
there was one hour (1910- 2010) when interferences caused problems during fading, quite good for the rest of the time.
@ James: Bitrates were still the same last night.
73, Simone

jbriggs
20-09-2005, 20:26
The BBC made some changes to the bitrate allowance available for the Orfordness MDI stream, so please let me know if the Sync loss problem is still there!
James

dk8cb
20-09-2005, 22:08
Hi,

Orfordness was received with a strong signal and a nice, short impulse response. At 20:46 UTC and at 21:27 UTC, there were resyncs despite a perfect looking spectrum, so I suppose that these were caused by data stream problems.
During the smaller dropout in between, the signal faded for a short moment.

Roland

simone
21-09-2005, 06:51
Hi all,
great results last night, see attachment
@ James: The sync loss problem occured at 2046 and 2127 as in Rolands log, but I have not noticed changes in the datastream yet, seemed the BBC were still using the old configuration.
73, Simone

jbriggs
21-09-2005, 15:07
Roland, Simone, it seems the changes were made after the end of the transmission early this morning, so hopefuly you will notice the difference today. The 1296kHz and 7320/9470 kHz content servers were swapped over.
Thanks, James

dk8cb
21-09-2005, 20:36
@ James

An interruption just happened at 20:30 UTC, see attachment. It didn't look like the well-known sync loss problem though.

Roland

dk8cb
21-09-2005, 22:08
Not a bad overall result.

Unfortunately, transmission is now scheduled to last only until midnight local time, I'd rather prefer it to continue for another hour as I have become used to it over more than a year.
Also see my previous report on the interruption at 20:30 UTC.

Roland

simone
22-09-2005, 05:22
Hi all,
good conditions last night, I also noticed the interruption at 2030, which was different from the problems in the past.
The dips at 1957 and 2014 were also Tx related, looks like the sync loss problem again, but I did not watch it at this time, sorry.
I think the end at midnight is OK, but it would be great to have a transmission in the early morning maybe starting at 0300 UTC, especially during winter as there are problems on most SW frequencies in the morning.

Concerning the changes, good audio quality and higher bitrate than on SW, time information and AF lists were broadcast again, not causing problems.
73, Simone

simone
22-09-2005, 18:41
Hi James,
besides the sync loss problem that is still there, the old "cold start problem" also occured occasionally this evening, I noticed it at 1719, 1731, 1741, 1743, 1753, 1759 UTC
73, Simone

simone
23-09-2005, 05:15
Hi all,
pretty good results, the sync loss problem occured 3 times (1834, 1937, 2054), see attachment
73, Simone

jbriggs
23-09-2005, 12:44
Roland, Simone,
Thanks for the comments on the sync loss and programme timings. I guess Roland you are a "late night" person and Simone an "early morning" one. From the start of winter schedule (end of CEST) 1296kHz will run from 0600 - midnight local. Of course I am happy to pass on the request for an extension of hours to the BBC! Good point about HF performing badly at 0300 UTC but I can't imagine there are too many people in Europe listening to HF at this time.
James

dk8cb
23-09-2005, 20:59
Hi,

I forgot to post my report on yesterday's reception. Here it is.

@ James
I guess you are absolutely correct with your assessment, at least in regard to me.

Roland

simone
24-09-2005, 06:26
Hi all,
quite good again last night, sync loss problem at 1934, the dip in the graph at 2101 seems also to be Tx related.
@ James: If 0300 UTC is too early, maybe 0530 (local) as a compromise for the winter schedule ;)
73, Simone

dk8cb
24-09-2005, 09:38
Hi,

I can confirm Simone's observations concerning the possible TX-related dropouts.

Roland

dk8cb
24-09-2005, 22:03
Hi,

quite good over long periods with a strong and steady signal.

I noticed a loss of sync followed by a TX interruption at 21:45 UTC.

Roland

simone
25-09-2005, 07:11
Hi all,
quite good results last night (with the known problems)
73, Simone

dk8cb
25-09-2005, 22:09
Quite a bit of interference today.

Roland

simone
26-09-2005, 05:06
Hi all,
quite good results, some dips due to the "sync loss problem"
73, Simone

jbriggs
26-09-2005, 14:03
We changed back to 9 kHz bandwidth. This happened about 13:45 UTC on Monday 26th. Please can you continue to use this thread for the next few days, I am very interested to find out if there is still a "sync loss" problem.
The BBC already made some changes to the bandwidth available for the MDI stream and this has not helped.
James

FritzWue
26-09-2005, 16:33
48712 Gescher - B525 - A43 - A1 - B54 - 48135 Muenster
I still have a little problem on this way when I get close to DLF Nordkirchen with 100kW on 549kHz.

FritzWue
26-09-2005, 16:34
Just a short one with 9kHz.
Driving home from 48712 Gescher.

dk8cb
26-09-2005, 22:06
Although I think that this should be posted in the 1296 kHz, 9 kHz bandwidth thread, here is my report:

I was only able to listen during the last half hour of today's transmission. Local interference together with fading caused a few dropouts. I did not notice any interruptions.

Roland

simone
27-09-2005, 05:02
Hi James, Julian,
great that you went back to 9 kHz as a test.
Bad news, the problem was still there last night :(, see attachment
73, Simone

simone
28-09-2005, 05:07
Hi all,
good results last night, besides the known problems.
Btw the transmitter was still on air at 0400 UTC this morning.
73, Simone

dk8cb
28-09-2005, 08:33
Hi,

last night, transmission continued after 22:00 UTC and I left everything running through the night. I did not see any sync problems until I went to bed at about 24:00 UTC, all the dropouts during which I checked the spectrum plot seemed to coincide with fading and interference.

Roland

dk8cb
28-09-2005, 22:05
Hi,

reception was quite good, however there seemed to be a sync problem at 21:35 UTC during which the receiver had to resync.
At 21:56 UTC, bandwidth was switched from 9 to 10 kHz, see next post.

Roland

dk8cb
28-09-2005, 22:07
Following a short interruption, bandwidth was changed from 9 to 10 kHz at 21:56 UTC, see attached plot.

Roland

simone
29-09-2005, 05:52
Hi all,
strong signal, good results from 1700, the sync loss problem occured again a few times ( like 1830 and 2135, the last dip was the break for changing the configuration back to 10 kHz)
73, Simone

FritzWue
29-09-2005, 16:21
Nice signal from 48712 Gescher to 48147 Muenster.
Dropouts caused by local interference when passing by certain companies or power lines.

dk8cb
29-09-2005, 22:24
Hi,

reception was quite good apart from what looked like sync problems at 20:20, 20:29 and 21:56 as well as an interruption at 21:51 UTC.

Roland

simone
30-09-2005, 04:31
Hi all,
very good results last night, the problems occured at
1843, 1933, 2021, 2029, 2151, 2156, see attachment
73, Simone

FritzWue
30-09-2005, 14:18
Good reception, dropouts still TX related:

dk8cb
30-09-2005, 22:28
Hi,

not really good here. Strong interference and fading at times. I suspect a sync problem at 19:09 UTC. Also strange to see, that there was a sync problem at 21:55/56 UTC, at exactly the same time as yesterday. Is this perhaps a remnant of the configuration change from 9 to 10 kHz at exactly the same time two days ago?

Roland

simone
01-10-2005, 03:40
Hi all,
strong signal, nearly perfect results from 1700 (sync loss at 1909, 2156), see attachment
73, Simone

simone
01-10-2005, 15:23
Hi all,
good results for more than 2 hours this morning before the signal got too weak ( about 3 hours after local sunrise, now around 0530 UTC), see attachment
Btw sync loss problem at 0624 and 0805.
73, Simone

Andreas
01-10-2005, 22:08
Hi!

Strong and stable in the beginning, so I made use of my whip antenna, which I would say normally is sheer madness for medium wave.....

Last 20 min. there was some fading and on-channel interference from Spain.

73, Andreas

FritzWue
01-10-2005, 22:41
Just the last half hour, good reception here with the loop:

dk8cb
01-10-2005, 23:50
Hi,

there seemed to be a sync loss problem accompanied by an extremely short break in transmission at 19:56 UTC.

A bit of fading and some interference from my neighbour's lighting power supplies during the last 15 minutes after my neighbour had come home.

Roland

simone
02-10-2005, 06:49
Hi all,
here is a complete 16 hours report of yesterdays transmission, seems there is a weak groundwave signal all day, skywave reception starting at 1430 but not reliable in the first hour, strong signal and good results from 1600.
(Sync loss problem and/ or interruptions at 1645, 1712, 1738, 1956, 2022)
73, Simone

df9rb
02-10-2005, 10:57
Hi all,

a daylight time test. Antenna for both receivers the EWE - The TS850 (2n graph) is better then the DRT1 with very weak signals.

Bernd, DF9RB

FritzWue
02-10-2005, 12:34
Good daytime results here at the dutch border:

simone
02-10-2005, 15:31
Hi all,
good results in the first 2.5 hours this morning, see attachment
(Sync loss problem at 0712, 0812, 0825, 0844)
73, Simone

hsseppo
02-10-2005, 19:25
Hi,

Here is my 100 minutes report of 1296 kHz in Helsinki. Audio quality is very good. 21.6 kbps / Mode A 10 kHz

73, Seppo

Andreas
02-10-2005, 20:29
...and here are the results from the noisiest spot in northern Germany

:mad:

However 73s, Andreas

dk8cb
02-10-2005, 22:10
Local interference level was high, there were also a few moments with fading. I suspect a sync problem at 19:50 UTC. There was also a sync loss at 21:49 UTC after which Dream would not regain sync by itself, strangely however, audio came back after switching the bandpass filter off, which had accidentally still been switched on.

Roland

simone
03-10-2005, 06:49
Hi all,
strong signal and good results last night.
The sync loss problem occured at 1519, 1641, 1828, 1921, 1940, 1950 (also a problem with DReaM to get sync again).
Simone

simone
03-10-2005, 10:45
Hi all,
good results this morning for 2.5 hours, sync loss at 0807(?)
Simone

dk8cb
03-10-2005, 22:22
Hi,

interference was strong at times and there was also fading, however the spectrum also looked perfect for most of the time. I believe there were sync loss problems at 20:15 and at 21:58 UTC. There may have been others as well but I was also busy with other things.

Roland

simone
04-10-2005, 06:12
Hi all,
good results last night
(Sync loss problem at 1743, 1758, 2015, 2124)
Simone

FritzWue
04-10-2005, 07:45
Morning result with the loop.
When I started SNR still was 10dB lower on the T-antenna.

simone
05-10-2005, 05:27
Hi all,
great results, no sync loss problem for more than 5 hours!
Simone

FritzWue
05-10-2005, 07:31
45127 Essen to 48712 Gescher via B224, A2, A31.
Problems when starting in town, problems in the middle caused by high voltage power lines at the Bottrop Autobahn crossing, higher snr to the end when driving slower.

dk8cb
05-10-2005, 10:01
Report attached.

Jos
05-10-2005, 18:59
Hi all,

Results for this evening.

Kind regards.

Jos.

simone
06-10-2005, 05:24
Hi all,
strong signal and good results last night.
(Sync loss fault at 1806, 1935, 2040, 2043, 2122)
Simone

dk8cb
06-10-2005, 08:45
A high local noise level and also strong on-channel interference last night.

Roland

dk8cb
06-10-2005, 09:06
Amazingly good daylight reception in Munich today. A few dropouts were however caused by local noise pulses due to a weak signal from Orfordness. I stopped logging during a deep fade but audio has since returned.

Roland

simone
06-10-2005, 15:21
Hi all,
perfect results in the first 50min this morning, see attachment
Simone

simone
07-10-2005, 05:21
Hi all,
perfect results last night, no sync loss problem.
Simone

dk8cb
07-10-2005, 20:11
A weaker signal today.

Roland

simone
08-10-2005, 05:04
Hi all,
good conditions last night. Unfortunately the snyc loss problem was back, causing the 6 dips in the graph :(
Simone

FritzWue
08-10-2005, 13:33
Startet on the wire antenna in the morning, still too much AM interference from Spain, then switched to the loop, so no problems any more, and switched back to the wire at noon local time when the interferer was gone with daytime attenuation.

simone
08-10-2005, 15:41
Hi all,
excellent results during the first two hours this morning, just one dip caused by the sync loss problem (0625), after 0900 UTC signal strength decreased rapidly
Simone

dk8cb
08-10-2005, 17:21
Report attached.

Roland

simone
09-10-2005, 05:05
Hi all,
great results last night, see attachment
(sync loss at 2019 and 2111)
Simone

dk8cb
09-10-2005, 15:38
No local interference but a lot of fade-outs.

Roland

simone
09-10-2005, 17:24
Hi all,
good results this morning, btw local sunrise now around 0540 UTC
Simone

carknue
09-10-2005, 21:08
results from this evening.

dk8cb
09-10-2005, 23:55
This was the first time that I noticed a Sunday music programme to last longer than the turn of the hour at 22:00 UTC. Unfortunately, regardless of this fact, Orfordness stopped transmitting a minute after midnight, local time (22:00 UTC), depriving me of the final parts of the symphony.

Roland

simone
10-10-2005, 05:13
Hi all,
good results except the sync loss problem occured quite often, see attachment
Simone

dk8cb
10-10-2005, 09:26
Not worth to listen to this morning. A weak signal.

Roland

FritzWue
10-10-2005, 17:11
Driving from town to town, 48147 Muenster to 48653 Coesfeld:

dk8cb
10-10-2005, 22:20
Until 21:37 (see mark in report), the receiver was accidentally connected to the shortwave dipole, which is of course electrically short for mediumwave. There was a lot of interference from co-channel stations on it. After I had switched over to the loop, reception became perfect.

Roland

simone
11-10-2005, 06:14
Hi all,
strong and stable signal last night, would have been a 100% result without these sync losses :(
Simone

FritzWue
11-10-2005, 17:00
Going from 46240 Bottrop to 48712 Gescher on the A31:

Per
11-10-2005, 18:57
Hi,

It's getting darker, so the reception on MW improves. Distance to Tx: 1300 km.
Time: 18:00 - 18:53 UTC. Result: 90 % CDA.

dk8cb
11-10-2005, 23:24
Dropouts were caused by fading.

Roland

simone
12-10-2005, 05:23
Hi all,
similar results as in the past nights, sync losses occured again, see attachment
Simone

FritzWue
12-10-2005, 12:45
There are still TX problems causing dropouts.
The SNR screenshot shows the loss at 11:40UTC.

FritzWue
12-10-2005, 18:16
Attached is a short zipped MP3 audio comparison between 1296kHz mediumwave and 7465kHz 41m just to show that the audio on mediumwave is better. :cool:

simone
13-10-2005, 05:23
Hi all,
good conditions again last night, the sync loss problem occured again a few times, see attachment
Normal audio bandwidth up to 13 kHz, compared to only 7 kHz on HF .
Simone

FritzWue
13-10-2005, 18:19
Going west from the outskirts of 33605 Bielefeld to 48712 Gescher via Beckum, Ahlen, Muenster.
The SNR during the second half was reduced by AM interference on 1296kHz.

simone
14-10-2005, 05:18
Hi all,
quite good results last night, the sync loss problem occured 3 times, see attachment
Simone

dk8cb
14-10-2005, 22:04
Quite good with a strong signal. I suspect at least one TX problem at 21:04 UTC.

It was my impression that audio sounded a bit different from what I am used to, in fact it sounded quite good.

Roland

simone
15-10-2005, 05:10
Hi all,
great results last night (2* sync loss problem), see attachment
Simone

Andreas
15-10-2005, 13:57
Considering I use a whip antenna in a VERY noisy surrounding it's a great result.

When I look at Simones log I can see, that two of the interruptions are Tx related, the others may be caused by local interference. Unfortunately MW is very sensitive to local distubances :(

73, Andreas

simone
15-10-2005, 14:26
Hi all,
good results in the first 2 hours, see attachment
Simone

Andreas
15-10-2005, 16:04
oooooops!

and here is the log I forgot to attach.

Greetings from Alzheim ;)

Andreas

FritzWue
15-10-2005, 20:29
Multiple on channel AM interference from the south:

dk8cb
15-10-2005, 22:16
Hi,

there was a period with quite a number of fade-outs when interference caused dropouts.
Very good for the rest of the time. Audio sounded rich and full.

Roland

simone
16-10-2005, 04:08
Hi all,
pretty good results last night, 2* sync loss problem, see attachment
Simone

simone
16-10-2005, 17:43
Hi all,
strong signal at the beginning this morning, most dips caused by the sync loss problem
Simone

simone
17-10-2005, 05:18
Hi all,
perfect except 4 dips caused by the sync loss problem
Simone

dk8cb
17-10-2005, 08:22
A bit of fading near the end and a sync problem at 21:34 UTC.

Roland

carknue
17-10-2005, 22:31
Not too bad. Really good sound quality. As usual with DRM Software Radio, there were much less dropouts, than the graph looks like.

dk8cb
17-10-2005, 23:33
Quite good apart from a single dropout shortly before the end of transmission.

Roland

simone
18-10-2005, 05:14
Hi all,
strong and stable signal for 5 hours, see attachment (2* sync loss problem)
Simone

FritzWue
18-10-2005, 07:13
Strong carrier from Spain even at nine...... :cool: (local time)

FritzWue
18-10-2005, 15:34
Going from 48341 Altenberge to 48712 Gescher.
Basically a good signal, don't know the reason for all short dropouts.
Some caused by driving under powerlines and bridges, but at least two were perhaps TX related.

dk8cb
18-10-2005, 22:05
Excellent reception. It would have been a 100% result if there wouldn't have been sync problems at 20:56 and 21:12 and short interruptions at 20:57 and 21:17 UTC.

The relative proximity of sync losses and interruptions, with the interruptions always following the former, which I have observed quite often now, seems to indicate a common cause.

Roland

simone
19-10-2005, 06:32
Hi all,
pretty good results (apart from the known problems, all 9 dips caused by sync losses) again last night.
So far I could not figure out a regular pattern concerning interruptions and the other sync loss problem.
Simone

dk8cb
20-10-2005, 00:09
Quite good. Unfortunately, I was only able to listen for half an hour.

@ Simone
I have not seen a regular pattern on sync problems and interruptions, I only think that often, an interruption follows a sync problem albeit not being predictable neither in its occurence nor in its delay. I just think that both phenomena do have a common cause.

Roland

simone
20-10-2005, 05:13
Hi all,
strong interferences last night, but anyway all 7 big dips in the graph were caused by sync losses.
Simone

FritzWue
20-10-2005, 14:55
Going from 48712 Gescher to 45128 Essen center.
A lot of high voltage powerlines and bridges when entering town.
Same way back on shortwave here:
http://www.drmrx.org/forum/showthread.php?s=&postid=21777#post21777

hsseppo
20-10-2005, 19:08
Hi,

Quite a good reception of the 1296kHz BBC in Helsinki.

Seppo

carknue
20-10-2005, 20:05
Not really good this evening.

dk8cb
20-10-2005, 22:05
In part a weaker signal as usual and a lot of fading.

Roland

FritzWue
20-10-2005, 22:06
Good this evening, plain to see:

simone
21-10-2005, 05:24
Hi all,
good results besides the sync losses, see attachment
Simone

dk8cb
21-10-2005, 22:07
Not bad to listen to, despite a few short dropouts. Signal became quite strong during the last hour.

Roland

simone
22-10-2005, 04:40
Hi all,
perfect besides the sync losses, see attachment
Simone

dk8cb
22-10-2005, 08:11
Daylight reception with slow fading. Almost identical results under low SNR conditions with both Dream and DRMSWR during the last 10 minutes of my logging period.

Roland

simone
22-10-2005, 09:05
Hi all,
perfect results for almost 2 hours this morning (apart from the 2 sync losses)
Simone

dk8cb
22-10-2005, 22:46
Hi,

some moments with fading.

Roland

simone
23-10-2005, 05:19
Hi all,
strong and stable signal, good results with both decoders, see attachment
Simone

dk8cb
23-10-2005, 22:02
Not so great.

But great music from WOMAD 2005!

Roland

simone
24-10-2005, 05:16
Hi all,
a few dropouts last night, at least 3 of the dips were caused by sync losses, see attachment
Simone

FritzWue
24-10-2005, 18:43
Daytime result driving from 46325 Borken via A31 and A2 to 44536 Luenen.

hsseppo
24-10-2005, 19:18
Hi,

1296 kHz was just good enough for listening.

73, Seppo

dk8cb
24-10-2005, 22:12
Excellent reception apart from what looked like a double sync loss problem at 21:53/54 UTC.

Roland

simone
25-10-2005, 05:06
Hi all,
good conditions last night, great results, dropouts caused by sync losses, see attachment
Simone

jbriggs
25-10-2005, 10:22
Sync loss problem update:
We checked the incoming data (MDI) stream and this is perfect at Rampisham at 21:53/54 yesterday, although there could be a problem with the satellite receiver at Orfordness. Also we have an IQ recording of the fault we will edit this down (from 2Gb file) and send it off for analysis.
James