View Full Version : 7320 kHz (BBC WS from Rampisham)
Hi all,
again perfect results, the only dropouts were caused by myself experimenting, see attachment
73, Simone
Hi,
very good reception until the transmitter left the frequency in the middle of a programme, shortly before the half hour.
Is Rampisham again short of usable transmitters? Is the TX being required for another transmission on another frequency?
Oh, as I am writing this (14:34 utc), there you are again!
What happened? Just a switching error?
Roland
Hi all,
shortly after the start of transmission, the DRM signal disappeared and there were some tune-ups. Quite good after that.
Roland
Hi all,
pretty good results for 4 hours, except 5min starting at 1207, maybe a Tx problem?
73, Simone
Hi all,
good results today, but again a 5min break in audio decoding like yesterday but 4min earlier, still no idea if it is a problem at the Tx or what is causing this, see attachment
73, Simone
Hi,
an excellent result today and one of the strongest signals I have ever seen on this frequency.
Roland
Hi all,
bad results and a very unstable signal, maybe a different beam was used than the past days?
73, Simone
Rene Schmitz
05-01-2005, 17:55
Hi Simone and all,
I can't second that. I've only logged the last 35 minutes, but that had 100% audio.
Cheers,
René
Hi,
good reception today but not perfect, also, signal strength was not like yesterday.
Roland
Hi,
again a day with a signal that was weaker than usual.
Roland
Hi all,
reults improved compared to yesterday but again deep fading in the second half, see attachment
73, Simone
Hi all,
back to a pretty strong and stable signal today after two days, see attachment
73, Simone
Hi all,
quite good today.
Roland
Hi,
signal was extremely strong today. This seemed to be the same for other stations on the band as well though, so a (suspected) ionospheric sounder that swept across the band caused the first little dropout at 10:40 UTC. After 14:00 UTC the usual interference set in, but I didn't listen after the news, too much soccer for me...
Roland
Hi all,
the best of my unattended logs today, see attachment
73, Simone
Hi,
today, there was a strange dropout, when the spectrum looked perfect but when both decoders lost sync and struggled to regain it for a while without immediate success. I guess that something was wrong with the data stream. Also, perhaps related to that, I could later notice at least three occasions in which the audio skipping effect occured, an effect that is otherwise only to be heard on 1296 kHz, where interestingly, it occured in a rather extreme form last night.
Roland
Hi all,
looked like there were some Tx and datastream problems today, I tuned in earlier and observed the same as Roland, loss of sync despite a good looking spectrum, also at 1107 DRM transmission was interrupted, only an AM carrier for some time, see attachment
73, Simone
Hi all,
great conditions except again a 5 min break, see attachment
73, Simone
...and here are the more detailed results, recorded every sec
73, Simone
Hi,
I recorded the same problem as Simone.
Roland
Hi all,
quite good results and again, the 5 min break occured an hour earlier today (still have not figured out whatīs wrong), see attachment
73, Simone
Hi,
I witnessed the same dropout as Simone did, but according to my logfile, it is only 1.5 minutes long.
Attached is the corresponding report. Very good reception otherwise.
Roland
Hi all,
low SNR in the first 45min, then back to the normal, later SNR dropped again twice for a few minutes, strange but I donīt know the reason, maybe a Tx problem, see attachment
73, Simone
Hi,
a low and constant SNR at the beginning accompanied by a somewhat strange spectrum that looked as if there were 20 dB weaker components of the DRM signal on both sides of the regular DRM spectrum. These components showed the same ripple as the regular 10 kHz wide DRM signal.
Suddenly, they disappeared and everything was back to normal.
Roland
I attach a comparison file of Simones measurements in Germany and the local measurements at the transmitting site. As you can see most of the problems clearly originate from the transmitting site :(
We changed satellite receivers today.
The Rx at the Tx station was the DReaM software (number 2 in the file)
Simone thanks for the file!
James
Here are combined results from Rampisham Tx site along with Simones recording.
Interesting to see sometimes problems caused by the logging file as ripples are seen at Rampisham when reception is OK for Simone. The problems seen yesterday with the MDI stream were not seen today. We did reboot the Content Server PC at the studio, this could have caused the MDI problems yesterday.
James
Some dropouts looked as if they were caused at the TX site. Otherwise quite good with a strong signal towards the end.
Roland
Hi all,
I can not confirm the first dropout in Rolands log, I probably missed the second one at 1100 by a few seconds, so only one of these breaks occured during my listening period but seems the problem with the datastream has not been solved yet.
73, Simone
Hi,
good reception with a strong signal from Rampisham. No problem despite carriers being present above and below.
Roland
Hi all,
pretty good results today, see attachment
73, Simone
Hi all,
when I began listening and logging (a little late) today, the signal was very weak, even with RF gain at full sensitivity, reception was very bad.
This seemded to be caused by an ionospheric disturbance.
Over the course of time, signal strength improved a lot and reception improved considerably.
I noticed two very short incidents when the spectrum was rather wide for a moment, the first of these is in the log, the second occured at 12:18 UTC, shortly after I had stopped logging.
Roland
Hi all,
a weak signal at the beginning, strange SNR behaviuor at 1112 maybe Tx related, for the other dips it is hard to say with these conditions today, see attachment
73, Simone
Hi,
after yesterday's weak signal, the situation today was quite the opposite. I don't think I ever saw such a strong signal from Rampisham on this frequency before.
But there were also problems. The well known P23S problem occured twice during the time I listened, also suddenly, SNR was low and the spectrum looked strange, there were sidebands on both sides of the DRM spectrum.
Roland
I took a screenshot after the SNR had dropped.
The spectrum plot shows strange sidebands, see attached file.
Roland
Hi all,
looks like there are still datastream and Tx problems at Rampisham: the datastream was lost 3 times during todays transmission ("P23S") and also the Tx tuning problem with the limited SNR stayed for nearly an hour, besides this, strong and stable signal, see attachment (including the spectrum at the low SNR period)
73, Simone
Hi,
again an extremely strong signal today.
Roland
Hi all,
too much fading in the first 1.5 hours, pretty good later, at 1422 there was again a Tx problem, see attachment
73, Simone
Hi,
there were problems with low SNR and a too broad spectrum today. After retuning of the transmitter, the problem vanished and SNR was normal again.
Roland
Hi all,
the Tx problem did not reoccur after the retuning of the transmitter today, perfect results for the rest of the transmission, see attachment
73, Simone
Hi,
today, Rampisham's signal was weaker than on the last two days. There seeemed to be some interference underneath the DRM signal.
Roland
Here is a combination of the transmitter site log and Simones:
There was a Transmitter fault at 13:36, and Simone stopped logging for a period. It's obvious when you look at the file!
James
Hi,
I can't really believe that the antenna feedline in Rampisham is 18 kilometres long! :D
Roland
Originally posted by dk8cb
Hi,
I can't really believe that the antenna feedline in Rampisham is 18 kilometres long! :D
Roland
lol :D:D
Hi,
today, there was a period during which the signal lost strength and when dropouts were quite common. Later signal strength recovered again.
I also noticed large differences in signal strength during fading periods.
Roland
Hi all,
pretty good results besides two dips probably caused by problems at the Tx site, see attachment
73, Simone
Hi all,
quite good concerning audio decoding, but the Tx tuning problem occured again for a period of 40min, see attachment
73, Simone
Hi,
Dream with bandpass filter and modified metrics switched on yielded a much better result than the DRMSWR in the presence of interference.
Roland
Hi,
all ionospheric paths from England to my location seem to be weak now. Orfordness was terribly weak last night and so is Rampisham today.
So many dropouts that it is just unbearable to listen to.
Roland
Hi,
today reception is hampered by problems:
- the ionospheric conditions are poor and the signal is weak, such that the slightest local noise peak as well as any interference signal causes a dropout
- there were many incidents in which the encoder did not produce the correct DRM signal but when it switched to the well-known P23S state.
No fun.
A normal listener would have switched off within minutes...
Roland
We have identified and fixed 2 problems:
1. Recent modifications to the transmitter to make operation easier (addition of some electrically operated co-axial switches) introduced some attenuation, and a slight change in level meant that some compensation circuits stopped working. This explains the step in SNR/MER observed by many people over the last few weeks.
2. The problems yesterday were caused by a monitoring PC here at the transmitter station & Multicast set up. In some more detail a PC was monitoring the DRM (MDI) stream coming into the transmitter site, but it was on a different subnet. Because we used multicast, sometimes the PC (rather than the DRM exciter) would reply indicating membership of the multicast group. The DRM exciter would see this reply as valid, and so would not reply itself. However the Satellite receiver/router did not accept the reply from the monitoring PC as valid. Therefore, sometimes the Sat Rx/router would stop sending packets and we then get the P23S state.
This problem was fixed by putting the monitoring PC onto the same subnet. I think we had a similar problem last year.
James
Hi James,
thanks for the information and congratulations on finding the faults.
But wasn't the MDI monitor originally switched on because there are also sometimes MDI packet loss incidents that occur out of the blue?
Have these also been eliminated?
Roland
Hi,
signal is again weak today and there are occasional dropouts.
Signal strength seems do decrease even more over time.
Roland
Hi Roland, yes you are correct there is still the original occasional packet loss, and we are continuing to look at this. We have monitoring software on the local network here looking at the incoming MDI stream.
James
Signal strength was better than yesterday but not yet back to normal.
There was also again a P23S incident.
Roland
Hi,
signal strength was again a bit better than yesterday, however transmission started 2 minutes late and signal disappeared shortly after and again later a second time for a short period.
The usual interferers were present during the last 2 hours but Dream with bandpass filter and modified metrics switched on could cope quite well.
All signals, including the interferers, became quite strong towards the end of transmission.
Roland
Hi all,
no luck receiving BBC WS in Switzerland, signal was too weak :(
73, Simone
Strong and very stable signal today (dropouts were caused due to local effects on my PC ;-)
73
Daniel
Hi all,
a weak signal today, but anyway good results, especially using DReaM according to the graph, results recorded with DRMSWR look a lot worse, but actually I was listening to the DRMSWR which was quite good. Only very few, the really deep dips, caused audible dropouts. Often when S/N was about 17-18 dB the audio light was red, but no problem for listening, UEP helped a lot in these moments without sounding funny as on some audio samples in the past. Usually results from DReaM are better with longer IRīs and interferences, but these problems did not occur today. So I wonder if both softwareradios handle the UEP decoding the same way concerning what is recorded in the logfile.
It seemed only one incident at 1333 UTC was related to Tx problems. I did not log 1300-1330.
73, Simone
Hi,
here is my report on today's transmission. I only listened live for the first half hour, the rest was logged unattended, so I cannot give definitive information on the cause of the dropouts. Guessing from my MP3 recording, it was perhaps the result of interference combined with a weak signal.
I also logged a similar dropout as Simone did at around 13:34 UTC.
Roland
Hi all,
a stronger signal today, nearly perfect results, I suspect the only dip was a problem at the Tx, see attachment
73, Simone
Hi,
transmission began with a very strong signal. However signal strength fell from then on into the 'midday hole' which I have observed regularly during the past weeks. Signal strength always later recovers.
Today, the signal stayed quite strong and did not show such a strong depression as observed on other days.
Roland
Hi all,
good conditions and a strong signal today, two dips due to problems at the Tx site, see attachment
73, Simone
Hi,
a strong signal again at the beginning, becoming a little weaker later.
From about 11:15 UTC on, I had a very strange interference. It may have been local but I doubt it. It first affected the lower third of the DRM spectrum, after a while, it disappeared only to return again later but now at about the center of the DRM spectrum. No idea what it was. It totally ruined my reception.
Roland
Hi all,
strong and stable signal until the break at 1132, I wonder what had been changed, after the signal came back lots of dropouts due to the weaker signal, see attachment
73, Simone
Hi,
my observations were similar to Simone's.
There were also several instances where the audio disappeared despite the MSC stream being received well. My impression was that the audio was already missing at the studio but perhaps this was somehow related to the dropouts that occured at other times. Unfortunately, I had to answer a phone call at the moment when the the large dropout occured, so I am unable tell what happened.
Roland
Hi,
not bad today. The first dropout was a result of my experiments with an USB sound adapter.
Roland
Hi all,
in the afternoon the configuration known from last yearīs IBC was used, this means the bitrate was reduced to 18.48 kb/s, the data service and AOD were on again, which nobody (except BBC?) is able to decode :(
see attachment
If thatīs going to be a regular service, I hope there will be some software available for decoding.
73, Simone
Hi all,
anyway signal strength was back to normal, good results, I suspect the dips were caused by problems at the Tx site or changes of the configuration, see attachment
73, Simone
Hi Simone, yes the transmitter did trip off at least once today. The only Log we had was from the DWT and this showed about 15 problems. In reality I think there were much less problems.
James
PS from the 5-9th Feb we will be using this transmitter to broadcast on 5875 kHz instead, to Paris. 09:00 - 16:00
Hi,
there were quite a few problems today:
- transmission started late
- there were several instances when both decoders lost lock despite a perfect looking spectrum
- there was one short instance when the spectrum looked "weird".
But signal was also strong today.
Roland
Hi all,
here are my results of the first hour, problems like Roland already mentioned, configuration like yesterday with special services (AOD, data service).
...later I tried to listen in my car, not much fun :( as the problems occured more frequently, losses of sync despite a good looking spectrum, a dozen times the exploding spectrum.., see attachment.
Hopefully this will be solved for the demo in Paris the next days.
73, Simone
Hi all,
the problems occured quite often today, transmission stopped at 1252 and is now being continued on 5875 kHz (with the same problems:()
73, Simone
Hi,
a strong signal like almost never before. If this is supposed to be the 140° beam then something is wrong.
Many interruptions of the same encoder-related kind and frequency as on 5875 kHz.
Roland
Hi all,
seems the problems have been solved! Great results for 4 hours, AOD and data service were still on, see attachment
73, Simone
Hi all,
a weaker signal today, but more important no Tx problems although AOD and data service are still on, see attachment
73, Simone
Hi,
a good signal over here. Despite that, there were a few very short audible dropouts, don't know were they came from.
Roland
FritzWue
12-02-2005, 15:17
Good signal, only minor problems during the last half hour.
Hi,
good reception but also the usual interference during the last hour of transmission.
Roland
Hi all,
a weaker signal from 1130, so interferences caused some dropouts in the last 25 min, but today again no Tx related problems, see attachment
Lower audio quality than usual as BBCīs special services are still on.
73, Simone
Hi,
a weak signal during my logging period. Interference caused many dropouts, especially - like every day - during the last hour.
The ever-present FSK signal was quite strong.
Roland
Hi all,
some dropouts using DRMSWR but no problem for listening, less problems with DReaM in the last 50 min of my log, see attachment
73, Simone
Hi all,
several dropouts due to a weak signal, see attachment
73, Simone
Strong and stable signal for the last 2.5 h. (Two single audio dropouts, probably not related to signal strength)
73
Daniel
Hi all,
signal was stronger than the past days, two dips in my unattended log probably Tx related, see attachment
73, Simone
A very strong signal today.
There were two dropouts during my logging period. During the first dropout, both decoders lost sync for no obvious reason, perhaps this was the result of a transmitter/encoder problem. During the second dropout, the signal disappeared completely.
Roland
Hi all,
some dropouts today due to Tx problems (I think), see attachment
73, Simone
Hi all,
seems the problems occur more frequently again, besides that conditions were quite good, data services are still on, see attachment
@ James: Same problems later today on vt digital.
73, Simone
Hi,
there were again transmitter problems today. Several times, the DRM signal disappeared completely.
Roland
Hi all,
today there was a strange 30min period when the signal got weaker until it was lost in the noise (all other frequencies that I tried (6095, 7240 kHz, Sines transmissions etc. were normal), later quite good conditions and only 1 dropout due to Tx problems, see attachment
73, Simone
Hi,
today, a strange ionospheric disturbance (Mögel-Dellinger effect) could be observed. At 10:52 UTC, signal strength decreased by 40 dB within a few seconds and the remaining signal strength was insufficient for proper decoding. Within the next few minutes, signal strength decreased even further until there was no more trace of the DRM signal.
From around 11:05 UTC, signal strength started to rise again until proper decoding was again possible as from 11:13 UTC.
During the period with no signal, I looked for other signals in the 41 m-band on a second receiver. There were almost no other signals, 31 m was also somewhat more quiet, higher frequencies however did not seem to be affected.
I checked for ionospheric propagation warnings on a space weather site, however there were none.
I cannot clearly confirm Simone's observation of a TX-related dropout.
Roland
Hi all,
very strong and stable signal today, no Tx problems, the one big dropout was probably my fault (?), see attachment
73, Simone
Hi all,
good results again today, see attachment
73, Simone
Hi,
quite good but signal was not as strong as on other days.
The dropout was caused by a signal that wandered across the band, perhaps an ionospheric sounder.
Roland
Hi all,
strong and stable signal, perfect decoding today, see attachment
73, Simone
Hi,
a very strong signal at times.
Roland
Hi,
there was one TX-related dropout today during which the DRM signal disappeared completely.
Roland
Hi all,
here are my results, same Tx related dropout as Roland mentioned, seems it happened again later, see attachment
73, Simone
Hi,
reception was excellent today.
The audio signal was delayed by as much as 1 minute and 12 seconds, a lot more than the "normal" (already large) amount of about 32 seconds.
Has someone increased the size of the transmit data buffer?
Roland
Hi all,
great results today, only an unattended log but from the indicated bitrate I would suspect it was the regular datastream without the dataservices and again using UEP, see attachment
73, Simone
Hi all,
two dips in the graph which probably were Tx related, later on mobile reception I did not notice such problems, see attachment
73, Simone
Hi,
good reception today with the exception of incidents with "exploding" spectrum causing dropouts.
The programme was again delayed by the same amount as yesterday.
Roland
Hi all,
some problems at the beginning, a slightly delayed start, good results then but why did todays transmission stop an hour earlier than scheduled?
73, Simone
Hi
good reception but as Simone has already mentioned, transmission ended one hour earlier than scheduled. Was the TX switched over to 9875 kHz?
Fortunately, "Pick of the World" featured the dramatic end of last week's drama from the World Play series which I had listened to on 1296 kHz but to the end of which I was kept from listening due to the regular DRM shutdown.
Roland
Hi all,
strong signal and pretty good results today, see attachment
73, Simone
Signal was so strong that I had to turn all gain controls down to minimum settings.
The programme was again delayed by over 70 seconds and there was also at least one incident in which the spectrum suddenly turned very broad.
Roland
Hi all,
quite good conditions today, also some Tx problems but of another kind than in the past, once it looked like a simulcast transmission
73, Simone
Hi all,
strong signal and great results today, see attachment
73, Simone
Hi,
a strong signal with faster fluctuations and a larger Doppler value than usual.
Roland
Hi,
today, there were new, yet unseen interference sources on this channel. There seems to be interference from an FSK signal which is almost centred on 7320 kHz as well as from a carrier, perhaps from an AM signal. Both interference signals don't seem to be correlated.
The FSK signal encountered in the past was about 2 kHz lower in frequency and usually came on at a later time.
See attachment.
Roland
And here is my report.
A strong signal, but some minor dropouts caused by the interference sources mentioned above.
Roland
Hi all,
quite good results today, the interference had been there before but in my area it is not very strong,so not causing problems, see attachment
73, Simone
Hi,
signal strength varied a lot today at my location. There was no visible interference, nevertheless there were a few dropouts for unknown reasons.
Roland
Hi all,
strong signal, a few strange dropouts, but not as many as in Rolandīs log, see attachment
73, Simone
Hi,
transmission started with the well known P23S problem today.
Signal was so strong that I had to turn down all gain controls to minimum.
Roland
Hi all,
some problems at the beginning of the transmission and once during my log, again the exploding spectrum occured, later quite good results, see attachment
73, Simone
Hi,
again an extremely strong signal today, perhaps the strongest I have ever seen on this frequency. But there were also moments when the signal was 30 dB weaker than during its moments of maximum strength, a difference, my front-end AGC couldn't cope with. This most likely caused the tiny dips in the log and prevented a 100% result.
Roland
Hi all,
strong and stable signal, no Tx related problems, perfect results, see attachment
73, Simone
Hi all,
same good conditions as on mobile recption earlier today, see attachment
73, Simone
Hi,
very good reception. Interestingly, the interference usually present during the last hour was not noticeable today.
Roland
Hi all,
perfect during my listening period, see attachment
73, Simone
A strong signal and very good reception also at my location.
Roland
Hi all,
pretty good , except these dropouts around 1300, probably Tx related, see attachment
73, Simone
Hi all,
pretty good results, from 1340 there was an interfering transmission causing the dropouts despite a strong signal, see attachment
73, Simone
...here is what it looked like in DReaMīs MER plot
73, Simone
Hi all,
pretty good results, for a short period the interference occured again, this time in the center of the spectrum, see attachment
73, Simone
Hi all,
perfect results today.
Hi all,
quite good results today, no idea what caused the dip at 1338, see attachment
73, Simone
Hi all,
a mostly unattended log today, looks perfect
73, Simone
Hi all,
strong and stable signal today, but one dip in the graph at 1248, see attachment
73, Simone
Hi,
good reception with one dropout, perhaps of local origin.
Roland
Hi all,
very good results today, see attachment
73, Simone
Hi,
not totally perfect but "only" rather good today.
Roland
Hi all,
pretty strong signal today, no audio decoding for 10 min at 1211 despite good SNR, see attachment
73, Simone
Hi,
good but not totally perfect today.
Roland
Hi all,
good results again today, see attachment
73, Simone
Hi,
quite good today.
Roland
Hi all,
today perfect conditions from 12h00 to 15h00
73
Daniel
Hi all,
perfect results and very stable signal also in the last hour today, see attachment
73, Simone
Hi,
at about 10:50 UTC, the DRM modulator in Rampisham switched into its well-known 'P23S' mode and interrupted transmission of the programme from then on.
Roland
Hi Roland,
transmission was back to normal at 1248, good results for the rest of the time, see attachment
73, Simone
Hi,
perfect reception today at least for as long as I listened.
Roland
Hi all,
pretty good results except a short period with dropouts caused by an interference (maybe a local problem), no "P23S test" today ;), see attachment
73, Simone
Hi all,
strong and stable signal, one dropout (maybe Tx related), see attachment
73, Simone
Hi,
reception was quite good today with the exception of a short interval when the spectrum suddenly turned very broad and when nothing could be decoded anymore.
During this interval, sidebands covered the entire bandwidth of my soundcard.
Roland
Reception was excellent today.
Roland
Hi all,
almost perfect reception also here for 4 hours
73
Daniel
Hi,
very good reception today.
Roland
Hi all,
perfect results today, see attachment
73, Simone
Hi all,
excellent, one of the best results ever on this transmission, see attachment
73, Simone
Hi all,
exellent result here today. Propagation conditions on this frequency seem to be perfect for my location.
Happy Easter
Daniel
Hi all,
great conditions again today, see attachment
Happy Easter
Simone
Hi,
very good reception once again.
Roland
Hi all,
it was an unattended log, looks perfect for 4 hours.
73, Simone
Hi all,
pretty good results like the past days, see attachment
73, Simone
Hi all,
still great conditions on this transmission, not sure if the one dip in the graph was a local problem or Tx related, see attachment
73, Simone
Good reception as usual.
Roland
Hi,
good reception again. I don't know why the plot looks so shaky.
Roland
Hi all,
good conditions but also a Tx problem, see attachment
73, Simone
Hi,
again a shaky plot but nevertheless perfect reception.
Roland
Hi all,
good results except a short period with a weaker signal and also a Tx problem occured again, see attachment
73, Simone
Hi,
Not so good at my location. At least not after 10:28 UTC.
Hi,
not quite as steady as on other days with many ionospheric paths.
Roland
Hi all,
pretty good results today, I suspect this time I caused the only dropout myself, see attachment
73, Simone
Originally posted by simone
I suspect this time I caused the only dropout myself ...
Hi Simone,
no, you didn't. There was a moment at the beginning of the news at 14:00 UTC, when the DRM signal suddenly disappeared and made room for an unmodulated carrier for a few seconds. Unfortunately, I had forgotten to switch on logging.
Roland
Hi,
and here is my report beginning shortly after the carrier-only incident.
Roland
Hi,
reception was good until suddenly, when a broadband noise strangely centred on 7320 kHz and modulated with sharp mains synchronous pulses, most likely of local origin, came up and completely ruined my reception.
I wonder what it was.
Hi all,
pretty good today, no datastream/ P23S problems like yesterday, see attachment
73, Simone
Good reception today.
Roland
Hi,
only a short report today.
Roland
Hi,
just a short report today.
Roland
Good reception with some minor glitches.
Roland
Hi,
good reception as usual.
For some time now, the broadcast is again delayed by "only" 20 seconds, not by more than a minute as it recently used to be.
Roland
Hi all,
pretty good results today, see attachment
73, Simone
Hi,
signal was not as strong today as during the past few weeks and there were a few dropouts. The cause of these was perhaps switching noise from the construction site across the road.
Roland
Hi all,
good results for 5 hours today, see attachment
73, Simone
Hi,
good reception today.
Roland
Hi all,
again pretty good results today, see attachment
73, Simone
Hi all,
strong signal and pretty good results (after a slightly delayed start), see attachment
73, Simone
Hi all,
signal was weaker than the past days, but no problem using the Sony/ telescopic antenna today, see attachment
73, Simone
Here is today's result from Munich.
Roland
Hi all,
again perfect results today, see attachment
73, Simone
Hi,
signal was a little weaker and there was a bit of interference.
Roland
Hi all,
one of the few transmissions with normal signal strength today, see attachment
73, Simone
Hi,
a little interference shortly after the start of transmission, very good for the rest of my logging period.
Roland
Hi,
a little interference, presumably of local origin, very good otherwise.
Roland
Hi all,
strong signal again today, perfect decoding, see attachment
73, Simone
Hi,
before transmission started, I could see an FSK (?) signal on frequency, I also had a noise peak at around 7314 kHz which moved around a little. No idea where it came from. I guess, the latter caused the dips in decoded audio and SNR.
Roland
Hi all,
good conditions again today, perfect decoding, see attachment
73, Simone
Also here: perfect
73
Daniel
Hi,
signal was not as strong as usual here and there was some interference.
Roland
Hi all,
good conditions again today, I did not notice any interferences, see attachment
73, Simone
Hi,
strange effects during the first half hour. No idea what it was.
Roland
Hi all,
some problems (P23S, exploding spectrum) in the first minutes, perfect after this, see attachment
73, Simone
Hi,
unfortunately, I only switched on a few minutes late, so I cannot confirm the initial problems. However, there were still a few dropouts for unknown reasons.
Roland
Hi all,
good conditions again today, after the break at 1140 the SNR was slightly lower than before, see attachment
73, Simone
Hi,
good reception today with two tiny dropouts.
Roland
Hi all,
almost perfect reception of BBC on this frequency.
73
Daniel
Hi,
this looks very similar to df8uo's result, so I guess, the dropouts were caused either by the same interference source or by a TX problem.
Roland
Hi all,
this frequency shows an almost constant SNR during 3 hours. Two dropouts in the beginning. The last hours there seems to be some "light interference". However i could not check because log is unattended. Weather is too good to stay inside and still no small portable DRM receiver available which fits on my bicycle ;-)
73
Daniel
Originally posted by df8uo
... and still no small portable DRM receiver available which fits on my bicycle ;-)
This brings up the idea to use the bicycle frame as an efficient loop antenna, otherwise you might perhaps have to drag a wire behind you. :D
Well, in some situations, a telescopic aerial might also be sufficient.
But imagine what might happen with the bicycle frame loop: "I cant drive that road, it goes from East to West. I have to drive at a 90° angle to that, otherwise I cannot listen to the rest of this programme ..."
Reception of Rampisham's signal was today hampered by heavy interference during the last half hour. I could not figure out what it was.
Roland
Hi all,
quite good results on my 4 hours unattended log today, same two dropouts at the beginning as in Danielīs results, so might be Tx related, see attachment
73, Simone
Hi,
as it should always be.
Roland
Signal strength decreased more and more during the second hour of transmission but later recovered again.
Roland
Hi,
there seems to be a TX problem today. SNR is very low and the spectrum is very broad.
As a result, there are a lot of dropouts.
Roland
Hi all,
seems the problem was solved at 1115, see attachment
73, Simone
Rene Schmitz
04-05-2005, 15:55
Hi Simone, Roland and all,
seems that problem came back later.
Otherwise the reception was essentially perfect. (The first dip was a computer op. )
Cheers,
René
Hi,
problems with heavy interference today.
There seems to be a strange noise source, perhaps a defective transmitter somewhere.
Roland
I have recorded an AM-demodulated sample of the strange interference signal underneath the DRM signal after the end of today's DRM transmission on 7320 kHz.
Here is an excerpt of it.
Any ideas what it could be and where it comes from? Can anybody else also receive it? It seems to be there quite regularly.
Roland
Hi all,
a very weak signal at the beginning, getting stronger after a few minutes, good results for the rest of the transmission, no problems with interferences, see attachment
73, Simone
Hi,
at the beginning, signal strength was less than normal and as a result, I had some dropouts due to interference from my DSL modem's internal power supply.
Then, signal strength suddenly fell to nothing within a few seconds. I checked the 41 m band for other signals on another receiver and found it to be completely dead. Frequencies around 9 MHz did not seem to be affected however.
The ionospheric disturbance was over within a few minutes and signal strength returned almost to its normal value.
Roland
Hi,
for a few days now, there are terrible clicks on BBC audio transmitted via 1296 kHz and 7320 kHz. They make listening quite annoying after some time. Interestingly, they occur more often on some programmes than they do on others.
The large dropout in my report was caused by an unidentifiable interference signal which came from below 7315 kHz and which slowly wandered across the DRM spectrum and further up afterwards. No idea what it was. In AM, it sounded like white noise with a little hum added.
The transmission started only after a delay of about three minutes.
Roland
Hi all,
Here is my log from this afternoon.
@Roland: I just listened "active" to the football transmission last half hour. There i did not recognize clicks. So i was lucky ;-)
73, Daniel
Originally posted by df8uo
@Roland: I just listened "active" to the football transmission last half hour. There i did not recognize clicks.
That's when I always switch off. ;-)
The clicks may well be some kind of resampling errors. They appeared a few weeks ago and I was told that the BBC changed a card in the control room after I had reported the problem. Then, the clicks disappeared, but now, they can be heard more often than ever before.
I can only hear them on good speakers however. When I once listened to a recording on primitive loudspeakers built into a TFT monitor, they were not recognizable at all.
Roland
Perfect reception. S9+10dB and quite stable.
Also here perfect.
@Roland: I connected today "good loudspeakers" (property of my daughter) and my small tube amplifier to the PC. The clicks were detectable (like old type writer clicks ;-) with this configuration. With my normal PC speakers they are not detectable. However my daughter forced me after short time to bring the speakers back to her room. No chance for further evaluation ;-)
73, Daniel
Hi,
here is my report for today. Quite good reception.
The clicks were there again and they do affect listening pleasure.
Roland
Originally posted by df8uo
With my normal PC speakers they [the clicks] are not detectable. However my daughter forced me after short time to bring the speakers back to her room. No chance for further evaluation ;-)
I think, one should also be able to hear the clicks very well on headphones connected in place of speakers.
Roland
Hi all,
a perfect last hour, despite a weaker signal and some fading, see attachment
73, Simone
Hi,
here is my report. Audio clicks were again audible on this transmission, albeit not very pronounced.
Roland
Hi,
signal was not strong and there were a few dropouts, most likely due to local interference.
Audio clicks could also be heard.
Roland
Hi,
not a strong signal today. Still slight crackles in audio.
Roland
Hi,
only a short report today.
Roland
Hi,
today, Rampisham's signal was weak at times and reception suffered from all kinds of interference during a few periods.
At first, I thought that the audio clicks had gone altogether but I later noticed a few on correspondent's reports.
Roland
Hi all,
strong signal and perfect reception all day, see attachment
Hi,
I could hear a few clicks during "The Interview", but none during the rest of my listening period with the exception of the time pips, but there have always been clicks ahead of the last pip (why?).
Roland
Hi all,
excellent today, see attachment
73, Simone
Hi,
not a strong signal today. During the first hour, the signal twice disappeared completely for a moment but came back after retuning (?) in the second incident. Later, I also noticed moments with broad spectrum.
Roland
Hi,
Good reception. There weren't any audio clicks.
Roland
Hi,
signal was a bit weak at the beginning but improved later on during the course of transmission.
Roland
Hi all,
pretty good results today, although since a couple of days the signal is weaker than it used to be.
73, Simone
Hi,
a perfect result today. Signal strength at my location seemed to have improved a bit compared to the last few days.
Roland
Hi all,
again a weak signal today like all week, quite good results anyway, see attachment
73, Simone
Hi,
transmission started with a very strong signal, at least at my location. Later it became somewhat weaker and signal strength moved up and down.
Roland
Hi,
again a signal that moved up and down in strength.
I could hear clicks on various programmes. They don't occur on every programme however. The phenomenon seems to affect only programmes from certain studios (eg sometimes from the sport studio) or those in which a lot of different clips are put together which originate from various sources or perhaps those which are edited in a certain studio. Strange!
Roland
Almost perfect today
73, Daniel
Perfect. Strong signal.
I did not notice audio clicks today.
Roland
Hi,
not a strong signal today and a few very short dropouts as a result.
Roland
Hi,
rather good reception today.
Roland
Hi,
only a short report today. I did not notice audio clicks today.
Roland
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