RTL on 1440 kHz

[Baldo34]

Hi all,
RTL in DRM now on 1440 kHz.
See screenshot.
73, Klaus

[Per]

Hi,

Quite amazing, I get 6 dB SNR here in Stockholm at 12:30 local time. (11:30 UTC). Both Sync and Data LEDs are active. The RFI Tx in Sankt-Petersburg is interfering with RTL.

[Baldo34]

Hi,
at the moment only S 7 near Kassel, but SNR 21 dB and full audio. Very good!
73, Klaus

[dk8cb]

Hi,

even in Munich at bright midday sunlight, about 30% audio may be decoded.

Roland

[LX1RE]

Hello,

Starting from today, DRM trial transmissions from Marnach on 1440kHz between 0:00 and 3:50 UTC on a regular base.

73,

Eugène

[radiomann]

Originally posted by LX1RE
Hello,

Starting from today, DRM trial transmissions from Marnach on 1440kHz between 0:00 and 3:50 UTC on a regular base.

73,

Eugène

Hi Eugene,
any idea when you will broadcast earlier in the evening on 1440? Or can't you do that with CRI on 1440 from 7pm?

Regards

Paul

[DRM-Fan]

Is this transmission going to be any good for South UK at least at night time ?

[radiomann]

I was always told the further North you are the better the signal would be on 1440, I lived in the North-West for 27 years and have lived here in the South- East for the past 8 years or so and not noticed any differance in reception, so hopefully we should get a decent reception where we are, fingurs crossed. Mind you we don't even know where they are aiming the signal, I would presume where they always have aimed it?

Paul

[lx1nw]

Antenna pattern should be ok for UK. DRM Transmission mode and bitrate might be a bit too high for skywave propagation, I hope reports will give us a clue on this matter.

73 Michel

[radiomann]

Looking forward to it Michel, no real MW/DRM tests anywhere, and as you have probably noticed I rate RTL highly and want you to suceed with DRM, but I do get frustrated at times.
Any info on what will be broadcast tonight?

Paul


Originally posted by lx1nw
Antenna pattern should be ok for UK. DRM Transmission mode and bitrate might be a bit too high for skywave propagation, I hope reports will give us a clue on this matter.

73 Michel

[carknue]

A good copy of a good old Mike Hollis show would be nice.

[radiomann]

Now that would be worth staying up for, I think they should use the Musicjam shows, be a good test I think, as for poor Mike he is stuck on Saga here in the UK


Originally posted by carknue
A good copy of a good old Mike Hollis show would be nice.

[radiomann]

Oh must say 1440 is booming in here as usual, with the usual fades:D

Will be interesting............

[dk8cb]

SNR is around 20 dB at the moment here in Munich but there is no audio at all.

Strong signal.

Edit 00:09 UTC: SNR has now risen to >23 dB at times. Still no audio.

Roland

[radiomann]

SNR 15-18 quite poor but like you no audio???????


Originally posted by dk8cb
SNR is around 20 dB at the moment here in Munich but there is no audio at all.

Roland

[carknue]

Very poor SNR here, due to too many reflections. Impulse response looks awful

[dk8cb]

Hi,

here in Munich, the impulse response is very long and - as always under such circumstances - the SNR achieved with Dream is much larger than with the DRMSWR due to the algorithm employed in Dream.

Still no audio.

There is also some fading. When the signal is weaker then, another on-channel carrier can be observed.

Roland

[DRM-Fan]

Pleased to be getting around 20 - 22db here in Brighton with my Elecktor but no audio ???

[radiomann]

Your doing better than me, now dropped to 12, who said analogue is dead?


Originally posted by DRM-Fan
Pleased to be getting around 20 - 22db here in Brighton with my Elecktor but no audio ??? :D

[MarkT]

Hi Folks,

Getting a maximum of SNR 22-23 up here in Edinburgh but no audio.

[dk8cb]

Are there changes going on?

SNR and decoding result have improved during the last minutes, see attached screenshot.

Roland

[DRM-Fan]

Yep also 15 - 18db now but no audio, oh sig has now gone totally hmmm!

[simone]

Hi all,
same problem as Carsten, IR is too bad even for DReaM.
73, Simone

[carknue]

I think that mode B is a must at nighttime. But also quite strong interference on 1440. I can hear now at least two AM Stations quite well.

[radiomann]

I blame Carsten, there too busy looking for that Mike Hollis show:D

[dk8cb]

Originally posted by simone
same problem as Carsten, IR is too bad even for DReaM.


Guess that the antenna's vertical radiation is very strong such that a large number of reflections are produced which lengthens the impulse response especially for people that are not so far away from the TX.

My report - so far - is attached.
It includes moments when the signal was switched off, so the decoding result is not representative!


Roland

[carknue]

Here is my report.

Roland, are you in Portugal right now? You really should use the TX info update ;-)

[MarkT]

Well` here is my log before the transmission died.

[johnn]

Like Roland my highest SNR after 12 mins. What is impulse response?

[dk8cb]

Originally posted by carknue

Roland, are you in Portugal right now? You really should use the TX info update ;-)

I know, but these are the coordinates which I found for the Marnach TX site on the internet.
They seem to be slightly incorrect. :D

Update: Coordinates in the above report are now correct

Roland

[dk8cb]

Hi LX...

can you put some signal on again?
Or has it zapped something?

Roland

[radiomann]

Well here is my report,

Paul

Can I go to bed now or is it going to get exciting?

:D

[LX1RE]

HI,

All to bed, we are thinking........., stay tuned for next night.

73,

Eugène

[radiomann]

Thankyou Eugene,
Any chance of a Mike Hollis show tomorrow:D

Regards

Paul

[radiomann]

Oh I forgot, goodnight all.

[dk8cb]

Originally posted by johnn
What is impulse response?

Impule response is the behaviour of a transmission channel in the time domain. It is the "output" of the transmission channel ( = the ionospheric path) at the receiving end, under the assumption that the transmitter is keyed with an ideal short pulse.

A DRM receiver has to permanently calculate an estimate of the channel's characteristics from the actually received signal (with the help of so-called pilots in the DRM signal) in order to recalculate the original undistorted shape - or at least an approximation - of the signal as it would look like at the input of the transmitting channel (ie the transmitter). Otherwise the signal would not be decodeable at all under multipath conditions.
These calculated channel characteristics can be displayed in time domain as the channel 's impulse response.
An ionospheric channel over which the signal travels from transmitter to receiver via various paths of different lengths and different associated time delays will have an impulse response with a peak for each of these ionospheric paths.
If the overall impulse response is too long, then data gets scrambled and decoding becomes difficult or impossible.

Roland

[simone]

Hi all,
here is my report, hope they will put some audio on next night :)
73, Simone

[lx1nw]

Hi,

I observed the transmissions from my home in Luxembourg-City and observed a large delay spread (mostly over 4ms) too. SNR varied from 13 dB up to 25 dB but was mostly around 15 dB, Doppler spread was rather low. I could also observe the co-channel carrier and the audio of this station was clearly audible after transmitter shut-down.

Receiver: FT-897 (without 455 kHz Filter), Decoder: Dream 1.1.6, Antenna: Wellbrook active Loop

73 Michel

[FritzWue]

I restarted logging several times in the beginning, so this is all I got.
Is this really a propagation problem or maybe a local rf feedback problem? :confused:

[FritzWue]

..by the way... the header did not fit, see red line:

[radiomann]

Audio looks set .......

Paul

[radiomann]

Screenshot 1a...

[radiomann]

Screenshot 1b......

[dk8cb]

Hi LX...,

the carrier was strong - but is anything else still to come or should we better go to bed?

Roland

[radiomann]

Originally posted by dk8cb
Hi LX...,

the carrier was strong - but is anything else still to come or should we better go to bed?

Roland


I was just thinking that, give us a sign:o

Paul

[MarkT]

22 past midnight not looking very good. Going to give it 5 mins then hit the sheets.
Well` as I write a carrier poped up yipppeee

[DRM-Fan]

No carrier here, dead as a dodo :-(

[dk8cb]

Aaaaah, there you are.

But only a mono transmission :-(

Roland

[radiomann]

SNR only 6 or 7
SN 9 +10 - SN 9 +20

Worked better this evening for me.

Paul

[carknue]

But even with Mode B too low SNR :-(

[radiomann]

Screenshot 1c........

[dk8cb]

Hi,

a rapidly changing impulse response that changes much faster than what I am used to from Orfordness transmissions on 1296 kHz.

Often the impulse response is too long and results in dropouts.

Roland

[dk8cb]

And this is how it sounds - including dropouts.

Roland

[DigiBC]

Hi,

my first test on 1.440 kHz is a bit disappointing: I just get some fragments of audio.

Impulse response looks better here (see attached file) but the average SNR is too low.

Regards - Jens

[dk8cb]

Originally posted by DigiBC
Impulse response looks better here (see attached file) ...

Hi Jens,

I don't consider your impulse response being a better one than mine. It is equally long with considerably large amplitudes outside the proper time interval.

It really looks a if RTL's antenna is not very good for nighttime DRM. Signal is nevertheless quite strong here and dropouts are absolutely not related to insufficient signal strength.

Roland

[radiomann]

Originally posted by dk8cb


Hi Jens,

I don't consider your impulse response being a better one than mine. It is equally long with considerably large amplitudes outside the proper time interval.

It really looks a if RTL's antenna is not very good for nighttime DRM. Signal is nevertheless quite strong here and dropouts are absolutely not related to insufficient signal strength.

Roland

Got to agree with you Roland on RTL's antenna, I'm getting quite a strong signal but no real audio:(

I think I might retire to snoozeland this is no fun:o

Paul

[dk8cb]

Hi,

today's result may not be representative, I also had a long impulse response on 1296 kHz today, although it didn't fluctuate as rapidly as it does on 1440 kHz.

During the last 10 minutes, there were fewer dropouts than before, or to be precise, almost none!

Roland

[carknue]

Its getting better now. Around 20 dB

[MarkT]

Log from 00.30 - 01.00, had a few audio dropouts one caused by my PC dialing up. Audio quality quite good, pitty not stereo but will probably come eventually.

Good night all.

[carknue]

Really stable the last minutes...

[dk8cb]

Hi,

I don't know why, but reception here is absolutely perfect now.
The impulse response still fluctuates a lot but it looks much nicer.

Roland

[DigiBC]

Hi!

Before I go to bed here are my results of the last minutes (slowly getting better after all).

The signal strength is not as good as expected. So the signal is very sensitive to the local noise level around here.

Now I'm looking forward to daytime transmissions. Maybe ground wave works better, even at a much higher bit rate. (On 1.296 kHz ground wave reception is very stable.)

Regards - Jens

[DRM-Fan]

Lot better the last 30 mins or so here :

[radiomann]

Can someone please explain why it is so difficult to get audio, check screenshot tell me whats wrong?

Paul

[dk8cb]

Hi,

here is my report. A lot of dropouts at the beginning, a period with perfect reception afterwards and some interference with a sometimes visible on-channel carrier at the end.

Roland

[johnn]

A 1 hour log with SNR improving after 12.45, but still not 100% audio. Thanks to Roland for his explanation on "impulse response." I thought it was multipath reception.
We can't receive 1296khz here from Orford Ness, so can't make comparisons!

[dk8cb]

Originally posted by radiomann
Can someone please explain why it is so difficult to get audio, check screenshot tell me whats wrong?

Try with Dream and check the impulse response!
The signal reaches you via too many differently long ionospheric paths which produces a large delay spread and violations of the guard interval.

Roland

[dk8cb]

Originally posted by johnn
I thought it was multipath reception.

Of course it was multipath reception. BUT: DRM can handle multipath reception very well, that's actually the smart thing about it, AS LONG AS the valid mode-dependant time limit is not exceeded.
If it is exceeded, then you have a problem.

Roland

[radiomann]

Originally posted by dk8cb


Try with Dream and check the impulse response!
The signal reaches you via too many differently long ionospheric paths which produces a large delay spread and violations of the guard interval.

Roland

I have downloaded the Dream software but it won't work, I am suppose to pay for it like the software I'm using?

Paul

[radiomann]

Well with a bad start, it didn't really get much better for me untill the last hour, I pluged my Sky satellite dish in to see what would happen, I think what ever I would of used at that time I would of got the same results??

A big part of my problem I don't understand how to build a good antenna, though I have had advice from people but no time and knowledge I am not techy I listen to radio and that is it.

Well I'm up in 2 hours so better have 40winks, now that I'm good at:D

My report.........

[radiomann]

Just have to say RTL on 1440 is booming in again on analogue just the odd fade, the sound quality on DRM may be better but I can constantly hear RTL on 1440 via analogue, with such bad reports is DRM the future? or is it early days?

Goodnight/Morning

Paul

[simone]

Hi all,
here are my disappointing results with DReaM and DRMSWR.
In contrast to other stations on MW, this signal does not seem to be directional at all. The main problem however remains the bad IR, interferences were not very strong.
73, Simone

[FritzWue]

Too late for me, here is my unattended log, in all much better than the first night. ;)

[carknue]

Here is my log from last night. Not usable! But it is already well known, that the stable covarage area on MW in DRM at night is much smaller than during daylight. Totally different to AM. I fear that RTL will have to reduce bitrate to 11 kbps at night like on 3995 khz.

[dk8cb]

Originally posted by FritzWue
... in all much better than the first night. ;)

Interesting to see that the first period of good reception in Fritz's report coincides with a similar 100% period in my report.

I wonder if something at the TX/antenna had been changed during that period.

Roland

[radiomann]

I hope there's another way than dropping the bitrate, 11kbps will sound terrible, maybe RTL can switch to DRM daytime/early evening soon to see the differance. I really thought it would of worked last night the signal strength was good enough, though I was getting Classic Gold on 1431 nudgeing in though usually that is a weak signal where I am.

An unmaned log tonight I think, good luck RTL.

Paul


Originally posted by carknue
Here is my log from last night. Not usable! But it is already well known, that the stable covarage area on MW in DRM at night is much smaller than during daylight. Totally different to AM. I fear that RTL will have to reduce bitrate to 11 kbps at night like on 3995 khz.

[FritzWue]

Originally posted by dk8cb


Interesting to see that the first period of good reception in Fritz's report coincides with a similar 100% period in my report.

I wonder if something at the TX/antenna had been changed during that period.

Roland

Yes, you can also see this in Carsten's SNR results....and also somehow in Paul's results. Wonder what was changed.

[DRM-Fan]

Originally posted by radiomann
I hope there's another way than dropping the bitrate, 11kbps will sound terrible, maybe RTL can switch to DRM daytime/early evening soon to see the differance. I really thought it would of worked last night the signal strength was good enough, though I was getting Classic Gold on 1431 nudgeing in though usually that is a weak signal where I am.

An unmaned log tonight I think, good luck RTL.

Paul




So I'm wondering if stereo DRM on MW is a bit ambitious and not really practical on the crowded nighttime European AM band ?
Maybe just an Anorak thing while RTL etc experiment for now ?

I hope we eventually get an X band like the US and Oz...ie 1611 - 1800khz for DRM

[radiomann]

Again agreed we do need an X band for DRM, havn't RTL just bought 2 new transmitters for 1440? I wonder what DRM would be like on 234 LW? Except for a few whistles I can get that all day & night.

I don't know we will wait & see, early days still.

Paul



Originally posted by DRM-Fan


So I'm wondering if stereo DRM on MW is a bit ambitious and not really practical on the crowded nighttime European AM band ?
Maybe just an Anorak thing while RTL etc experiment for now ?

I hope we eventually get an X band like the US and Oz...ie 1611 - 1800khz for DRM

[carknue]

Hmm, just some thoughts for RTL. Mayby too much power that caused an extreme skywave pollution. Maybe a trial with lower power (10-70 kW) should be run.

On 1296, 693 , 855, 1485 and 1611 the Impulse response is always much clearer. and they all have less power. Maybe different antenna.

[dk8cb]

Originally posted by carknue
Mayby too much power that caused an extreme skywave pollution.

I don't think that power is the problem. The ionosphere is mostly linear, despite the small nonlinearity evident in the "Luxemburg"-effect that got it's name because it was first observed on transmissions from Luxemburg in the 1920ies. Therefore, more power will just increase signal strength at the receiving end.
But if an antenna is used that features a radiation pattern with a component at a high vertical incidence angle, the number of ionospheric paths is greatly increased and the time delay spread is large and will cause violations of the guard interval.

Today I have read that, even if the antenna is of a low radiation angle type, surrounding hills at the TX site may cause the same overall effect.

I think that they have two types of antennas in Marnach, perhaps one should run a test with the other one tonight.

Roland

[dk8cb]

Hi all, with not much problems from other on-channel stations on this frequency, one might try another experiment at the receiving end:

If a ferrite or a loop antenna is used for reception, one might turn it by 90 degrees from horizontal to vertical or vice-versa, this will decrease signal strength a lot and make the antenna non-directional in the horizontal plane but it will also favour the horizontally polarized component of the received wave and it will also attenuate vertical incidence signals.

Roland

[FritzWue]

Acc. to today's announcements on the german mw programme:
RTL regular DRM transmissions on 1440kHz
from 1. January 2005 daily
08:00 to 17:00 UTC
00:00 to 03:50 UTC

EDIT:
I heard that recorded announcement twice today.
They said that receivers will be available from summer 2005.
No more info given.

[DRM-Fan]

Originally posted by FritzWue
Acc. to today's announcements on the german mw programme:
RTL regular DRM transmissions on 1440kHz
from 1. January 2005 daily
08:00 to 17:00 UTC
00:00 to 03:50 UTC

But what mode I wonder ?

[radiomann]

What's going to be on between 17.00 - 00.00 (UTC) Religious & CRI maybe?

Paul



Originally posted by DRM-Fan


But what mode I wonder ?

[dk8cb]

Originally posted by FritzWue
Acc. to today's announcements on the german mw programme:
RTL regular DRM transmissions on 1440kHz
from 1. January 2005 daily
08:00 to 17:00 UTC
00:00 to 03:50 UTC

But this information hasn't made it to their website yet. There, they still advertise 1440 kHz with the (translated) words: "RTL Radio may again be received in the greater part of Germany and especially in Northrine-Westphalia on good old 1440 kHz, one cannot escape us at all. If your car or kitchen radio still has a MW or AM button, give it a push ... 1440 kHz."

Roland

[radiomann]

Now would be a good time for RTL to test DRM, It would give me something to do:D

Paul

[dk8cb]

Originally posted by radiomann
Now would be a good time for RTL to test DRM, It would give me something to do:D


You might as well use the time to look around the web for articles on how to build a decent medium wave receiving antenna.

Read e.g. here:
http://dspace.dial.pipex.com/town/pipexdsl/r/arar93/mds975/Content/aerials1.html

http://www.hard-core-dx.com/nordicdx/antenna/loop/hulaloop.html

Roland

[radiomann]

Originally posted by dk8cb


You might as well use the time to look around the web for articles on how to build a decent medium wave receiving antenna.

Read e.g. here:
http://dspace.dial.pipex.com/town/pipexdsl/r/arar93/mds975/Content/aerials1.html

http://www.hard-core-dx.com/nordicdx/antenna/loop/hulaloop.html

Roland

Thank you Roland,
I have had some very nice help from John (G3VRF) and I am looking at building the same as he has made but I need a capacitor, so stuck at the moment.

Paul

[dk8cb]

Originally posted by radiomann
... but I need a capacitor, so stuck at the moment.


Don't you have an old disfunctional tube or transistor set somewhere in the attic from which you could salvage one?
No shops around where you could get one?
Over here, they sell suitable old capacitors for about 5 Euros.

Roland

[radiomann]

Oddly enough I don't have an old radio, I have plenty of radio's but all in good use, I don't know of any shops, maybe Maplin here in the UK I will check them out, the other problem I have is lack of time I work 6 day,s a week and have very little time with my family, maybe easier to buy one? I thought of a Wellbrook ALA 1530P, I'll save my pennies.

Paul


Originally posted by dk8cb


Don't you have an old disfunctional tube or transistor set somewhere in the attic from which you could salvage one?
No shops around where you could get one?
Over here, they sell suitable old capacitors for about 5 Euros.

Roland

[carknue]

I really hope, that they haven't signed a 20 years contract with CRI. Or will they broadcast CRI also in DRM? But I don't think so.

[radiomann]

It was a 3 year contract which runs out in January, but maybe it's been renewed? I think RTL should use 1440 to lease out and make money, they need better frequencies to concentrate with DRM. I think they would be better to use 234 Long Wave or do the French listen on that frequency a lot?




Originally posted by carknue
I really hope, that they haven't signed a 20 years contract with CRI. Or will they broadcast CRI also in DRM? But I don't think so.

[dk8cb]

Originally posted by radiomann
I think they would be better to use 234 Long Wave or do the French listen on that frequency a lot?

France seems to be the only country where a substantial number of people still listens to long wave. There is also Europe I transmitting from the german/french border (but inside Germany) with a highly directional antenna and a lot of power (2 MW) into France.
There is also France Inter in Allouis, again a 2 MW transmitter.

Edit: I forgot to mention Radio Monte Carlo, also transmitting on longwave into France with "just" 1200 kW.

Roland

[lx1nw]

Hi,

I logged the DRM transmissions from last night on our longwave station 35 kms south of Marnach. At this distance there is only groundwave propagation, so reception results are much different from those recorded at larger distances.

73 Michel

[dk8cb]

A much better impulse response than yesterday but conditions on 1296 kHz were also much different from yesterday.

Roland

[DRM-Fan]

Not bad so far with peak of 22.4db, seem to be less drop outs tonight ? but only MONO mode again :-(

[carknue]

Wow, what happened tonite? 28 dB! clear IR! 100% audio since 10 minutes now!

[radiomann]

A lot better for me also tonight even with my crap antenna:D

Paul

[FritzWue]

wow!

Wattn Siggenaal !!!

[dk8cb]

Originally posted by carknue
Wow, what happened tonite? 28 dB! clear IR! 100% audio since 10 minutes now!

Almost perfect over here as well!
I suspect that they have switched to another antenna or are propagation conditions really that much different from yesterday?

1296 kHz was very good tonight as well.

LX.. please give us more insight!

Roland

[radiomann]

There's something different tonight, but 1611khz was much better for me.

Paul



Originally posted by dk8cb


Almost perfect over here as well!
I suspect that they have switched to another antenna or are propagation conditions really that much different from yesterday?

1296 kHz was very good tonight as well.

LX.. please give us more insight!

Roland

[lx1nw]

Hi, nice results in Luxmbourg City:

SNR around 24 dB (dream; FhG: 22 db)
100% Audio decoding
ugly spectrum, weird impulse response
no dropout so far !
receiver indicates +- 20 dB less fieldstrength than before 0000z

antenna: passive loop (40 cm diameter) indoor (ground floor)
receiver: Aor 7030

73 Michel

[carknue]

Maybe less power tonite? But signal is still very strong here. Not a single dropout so far. 26-29 dB! Maybe they use the german beam instead of the UK beam tonite.

[radiomann]

Screenshot 1e......

I presume Winradio does'nt like going over snr 20? Though in the past I've had snr 23 for a nanosecond.

Many of my dropouts are caused by me on the net.........

Paul

[dk8cb]

Hi,

sometimes, an interfering carrier is visible in the spectrum, see screenshot.
However so far no problem with it.

Roland

[radiomann]

Soooooooooo happy I forgot, try again.........

[lx1nw]

The antenna in use today is the nighttime areal. Power should be the same as yesterday. I suspect the propagation to be somewhat different from the days before. IR still looks terrible, but the echos falling out of the guard intervall are less important.

73 Michel

[DRM-Fan]

Originally posted by lx1nw
The antenna in use today is the nighttime aerial. Power should be the same as yesterday. I suspect the propagation to be somewhat different from the days before. IR still looks terrible, but the echos falling out of the guard intervall are less important.

73 Michel

Over 26db here, could'nt they have tried stereo mode asgain with the nightime ant ?

Varying sigs with Dream 1.1.6cvs and the DRM s/w radio running together...

[dk8cb]

Hello LX....

Just curious:
Is this already coming from the new Telefunken TX or is it the old TX?

Is it a tube or are semiconductors used as final amplifiers?

Roland

[carknue]

Hmm, there must been changed someting. the AM audio before sounded as distorted as the days before...

[carknue]

I noticed RTL with the new TX in AM mode must be the only station with the exact bandwith of 9kHz;-) So AM sounded worse than with the old TX.

[dk8cb]

Originally posted by carknue
Hmm, there must been changed someting. the AM audio before sounded as distorted as the days before...

'Normal' multipath propagation is sufficient to make AM sound distorted but if the impulse response is still within its limits, DRM can easily cope with that.

Roland

[lx1nw]

The new Telefunken Solid State is being used for DRM transmissions. (c.f. General Topics / Luxembourg to run AM DRM tests thread). We can use parametric stereo in the future, but I don't know if it will sound good @ 18.4 kbps.

Michel

[simone]

Hi Roland,
concerning the TX have a look at the
Info from Telefunken/ Mr. Huber (http://www.telefunken-sendersysteme.de/News_Presse/RTL_digital_MW/body_rtl_digital_mw.html) (only in German)
73, Simone

[dk8cb]

Originally posted by carknue
I noticed RTL with the new TX in AM mode must be the only station with the exact bandwith of 9kHz;-)

This seems to be a widespread phenomenon. After looking around the bands for some time now, I have come to the conclusion that DRM stations are the almost only ones that stay within their bandwidth limits.

The others just don't seem to care...

Roland

[dk8cb]

Originally posted by simone
concerning the TX have a look at the
Info from Telefunken/ Mr. Huber (http://www.telefunken-sendersysteme.de/News_Presse/RTL_digital_MW/body_rtl_digital_mw.html) (only in German)


I know this link and I have already published it here on the forum a while ago, but this doesn't answer the question whether the new TX is already in operation or whether it is still in the planning or erection phase.

That's why I asked.

Roland

[lx1nw]

It's up and running right now ...

[dk8cb]

Hi LX,

conditions are good, so couldn't you perhaps try another higher bitrate as long as everybody is listening?

Roland

[lx1nw]

There will be more nights for extensive mode and bitrate tests ...

[DRM-Fan]

Log for last 36mins :-

[radiomann]

Well to be fair they should use the German beam as the German service is staying on 1440, the UK could be getting a Short wave frequency, mmmmm.........

Paul


Originally posted by carknue
Maybe less power tonite? But signal is still very strong here. Not a single dropout so far. 26-29 dB! Maybe they use the german beam instead of the UK beam tonite.

[MarkT]

Wow` things are really "cooking" here as well...

[dk8cb]

Another observation:

Signal is by far not as strong here as it usually is on transmissions from Orfordness on 1296 kHz using the same receiving antenna.

Roland

[radiomann]

Cooking here as well, that reminds me of Bob Stewart, it was one of his jingles.

Paul


Originally posted by MarkT
Wow` things are really "cooking" here as well...

[carknue]

Hmm, only condition changes? Now almost one hour without any dropouts and 28 dB burnt into my TFT screen:D. But what are the normal conditions? Like the last two days or like now?

[dk8cb]

Originally posted by lx1nw
There will be more nights for extensive mode and bitrate tests ...

But you can't expect us to listen every night!

Now, everybody who is interested is already here. Some are still on holiday as well and don't have to get up as early as they normally do...

Roland

[radiomann]

It should be like now, just before I switch to DRM from analouge the signal is good it's been the same for the past couple of nights, maybe my crap antenna is'nt that bad afterall rock solid at the moment.

Paul


Originally posted by carknue
Hmm, only condition changes? Now almost one hour without any dropouts and 28 dB burnt into my TFT screen:D. But what are the normal conditions? Like the last two days or like now?

[DRM-Fan]

Originally posted by lx1nw
There will be more nights for extensive mode and bitrate tests ...

Incl stereo mode also as on the first night ?

[radiomann]

Totally agree, I'm back at work next week 6 days a week, be daring change the bitrates, throw in a few 208 jingles, I can pick this up on satellite, give us a real test, only jocking.

Paul




Originally posted by dk8cb


But you can't expect us to listen every night!

Now, everybody who is interested is already here. Some are still on holiday as well and don't have to get up as early as they normally do...

Roland

[radiomann]

Yes, why it's working well, see how far you can push it, STEREO STEREO please.


Originally posted by DRM-Fan


Incl stereo mode also as on the first night ?

[dk8cb]

Hi,

now, the impulse response starts to lengthen over here and there are occasional albeit very short dropouts.
IR fluctuations are however much slower than yesterday.

Roland

[lx1nw]

Sorry - this will have to wait as there is no one at the station able to change the settings right now.

[radiomann]

Yes, snr dropping here, no dropouts at the moment, looks like Classic Gold 1431 wants to spoil the party.


Originally posted by dk8cb
Hi,

now, the impulse response starts to lengthen over here and there are occasional albeit very short dropouts.

Roland

[carknue]

Ok, it was only propagation canges. Conditions get slightly worse here right now. SNR drops someties below 20 dB. And first dropouts occur.

[dk8cb]

Originally posted by lx1nw
Sorry - this will have to wait as there is no one at the station able to change the settings right now.

It is only us 'fools' who are still doing it live! :D

Roland

[radiomann]

Originally posted by lx1nw
Sorry - this will have to wait as there is no one at the station able to change the settings right now.

I'm not surprised it's the middle of the night:eek:

Paul

[FritzWue]

More fading now, but still very good.
Great night for Radio Luxembourg! :D

[MarkT]

Hi again folks,

What a difference a night makes, nearly Dream decodes 100%, ah well there`s always tomorrow night...
Enough "playing" for today.

Night all.

[carknue]

The worst thing is, that there is even nobody in the studio. Just a computer playing music from a hardisc .

[dk8cb]

Originally posted by MarkT
nearly Dream decodes 100%

Dream can handle signals with long impulse better than the DRMSWR does. If you have both software decoders running in parallel, you will see how SNR values from both decoders drift apart under long IR conditions. Dream then lengthens the time window used for decoding and it processes a bit more signal energy that is contained in the longer time window which will yield a better SNR.

Roland

[lx1nw]

Time for a few hours of sleep here too ... Thanks for staying up that long and providing reception impressions from all around.

73 Michel

[FritzWue]

I've never seen such high SNRs around 28 to 29dB on medium wave before.

[carknue]

Yeah, but I only see the difference between Dream and DRM software in the graph. I hear no noticable difference in audio.

[dk8cb]

Originally posted by carknue
Yeah, but I only see the difference between Dream and DRM software in the graph. I hear no noticable difference in audio.

I have had quite a few occasions in the past, especially when mode A was used, when the DRMSWR did not deliver audio anymore but when Dream still did.

Roland

[radiomann]

Originally posted by FritzWue
More fading now, but still very good.
Great night for Radio Luxembourg! :D

"Radio Luxembourg The mighty 1440" anoraks at the ready:D

[dk8cb]

Originally posted by radiomann


"Radio Luxembourg The mighty 1440" anoraks at the ready:D

Didn't it say "The mighty TWO O EIGHT"?

But what's the "anorak" thing? :confused:

Roland

[FritzWue]

http://old.anorak.org/

!!! http://www.geocities.com/woodleyuk/index2.htm !!!

[radiomann]

The Great Two O Eight, The mighty 1440 AM, the anorak thing is people like me who remembers old stations and remembers everything about them, sad really.


Originally posted by dk8cb


Didn't it say "The mighty TWO O EIGHT"?

But what's the "anorak" thing? :confused:

Roland

[dk8cb]

Originally posted by FritzWue
http://old.anorak.org/

But those were others.

208 was just broadcasting from a foreign country which makes a huge difference.

Roland

[radiomann]

Originally posted by FritzWue
http://old.anorak.org/

!!! http://www.geocities.com/woodleyuk/index2.htm !!!

Now that's anorak;)

[radiomann]

Well many dropouts now, down to snr 15 1431khz playing havok, I'll leave it logging see what I get when I wake up.

Goodnight all, to those of you thats left.

Paul

[FritzWue]

Where is the audio gone?

Edit:
Aaaah, here we go again.
I also leave it running, good night everybody.
Was a great night for DRM!

[dk8cb]

Hi all,

so here is my report for tonight.

Quite a 'power play' of users here tonight. :)
(Yes I did listen to 208 as well when I was aged about 13, not in the UK but in southern Germany, where reception was much worse!)

Audio has just disappeared, although 100% is still decoded and it then reappeared for only a very brief moment as if a CD would hang ...


Roland

[radiomann]

Originally posted by FritzWue
Where is the audio gone?

Typical, Iput my head down on the setee so not to disturb the family the audio goes, go back to the computer it comes back, gone very bad now though, last night at about 2.55 it worked ok so while I drift of we will see, goodnight again.

Paul

[lx1nw]

Here the entire log of tonight's transmission.
Location: Luxembourg City
RX: FT-987
Antenna: active loop

Regards,

Michel

[simone]

Hi all,
here are my results for last night, quite good till 0110, then IR looked bad like in the nights before. Conditions improved again in the last 45min. Quite a difference between DReaM and DRMSWR as usual with long IRs, see attachment (please ignore results of the first 25min, I had been experimenting)
73, Simone

[FritzWue]

I was a little late,
used a different pc, as the one used before makes noise on 1440kHz,
and dream froze an hour after the end of transmission on that second pc,
so no max. snr.
Nevertheless the best results so far.

[radiomann]

Last nights report, after 2ish it didn't really get any better for me. though the first 2 hours made good listening.

Paul

[carknue]

Hi all,

here is my log from last night. It is a comparision between DRM SWR and Dream. I would call both results perfect! Only very few dropouts in the middle part. But these droputs were audible with both software radios, Dream only plots a bit more optimistic. But they were very short, that they didn't matter. It was really a total contrast to the two nights before.

The sound quality was very good. At least the best we can get in the night at the moment. DW brings only 11kbps at that time. Mono is OK and I'm sure that sounds better than 18.3 in ps.

For Mode A, the IR would be mostly too wide. So Mode B was the perfect mode.

[FritzWue]

Carsten's and my results during the first half of that transmission show opposite SNR value behaviour.
Would be interesting to know what radiation pattern was in use, although this does not necessarily affect the SNR.
Carsten is in the east, I'm in the north.

[N_Scheer]

Hi, DRM's


Thanks for the numerous reception reports!
Tonight at our transmitting centre in Marnach we used the 1/4 wave antenna, which is usually our night aerial and a DRM power of 120kW provided by one new Telefunken solid state transmitter, the second being in standby.

The next few weeks, we are going to test different DRM modes, antennas and also different DRM power, so don't be disappointed, if sometimes the reception isn't perfect, but stay tuned.

Merry Christmas and a great happy DRM year!


Nico

[radiomann]

Looks like before i start I'm on a no winner, bad interferance already on analogue:mad:

[LX1RE]

Hi,

We got serious troubles starting with our DRM TX's. Hopefully we can fix the problem.

73,

Eugène

[carknue]

Oh, we hope the best

[MarkT]

I think I am picking up some transatlantic Dx from the states during the "silence"

[carknue]

It sounds more like russian to me. But nice music. Must be the 1600 kW monster.

[Baldo34]

No monster, 20 kW from Beograd.

[Baldo34]

Excellent signal from RTL at the beginning of the transmission.
See screenshot.
73, Klaus

[carknue]

Not so good, some dropouts, but p-stereo tonighte. Improving now. Unfortunately with the new window feature I'm not able to run DRM SWR in parallel. Dream uses too much CPU power now.

[MarkT]

Good reception here 25-27 SNR and in glorious stereo.

[jimbo]

Strange, but djring the first ten minutes - until 0018, the sound was quieter then normal, but it sounded as if there was FM quality on an AM signal - very odd indeed. What was going on?

[carknue]

Getting more and more stable. Only 5 khz audio bandwidth now. But no dropouts anymore.

[johnn]

My 1st time with Dream! Very stable in the fades. DRMSWR lost audio at times. Able to run both at the same time...

[MarkT]

Hi all,

Here is my log for tonight, generally good reception but don`t know what happened at 0.58 hrs UTC. It was like a break in transmission or something.

Good night folks.

[dk8cb]

Originally posted by carknue
Unfortunately with the new window feature I'm not able to run DRM SWR in parallel. Dream uses too much CPU power now.

No such problem over here. Dream still uses approximately the same amount of CPU power here with four evaluation windows open.

Roland

[tacitus-ms]

Although here in Münster the analogue transmissions of RTL 1440 can always be received very well at day and night, the DRM transmissions of the last nights could hardly be decoded. Always a very low S/N and violations of the guard interval. See screenshot I made about 2:00 GMT. It is very sad, but RTL seems to have the same problems we already know from DW Wertachtal 3995 kHz. The low datarate of 15,32 causes a ridiculous sound quality, but it does not really reduce the drop out rate to an acceptable value. Very sad, I am very disappointed that the usage of DRM reduces the coverage area of RTL 1440 so strong. Because of the guard interval problem I am afraid that Mode A will never work and Mode B only with values we know already from DW 3995, that means no realistic chance for a relaunch of RTL, because such low sound quality will never be accepted for music.

Receiver: FRG 100 with Sat-Schneider Mixer Unit, Pentium4 2 GHz PC with good Creative Labs soundcard, ALA 1530 Loop mounted on a rotor.

[dk8cb]

Hi,

does anyone else have this strange off-centre interference? Looks like a carrier but very much off the centre, see attached WMER plot.

However, so far, I have not managed to see it in the spectrum plot quite unlike the carrier that is right on channel.

Roland

[carknue]

No, no off center carrier here. Must be a local source.

[tacitus-ms]

Originally posted by dk8cb
Hi,

does anyone else have this strange off-centre interference? Looks like a carrier but very much off the centre, see attached WMER plot.

However, so far, I have not managed to see it in the spectrum plot quite unlike the carrier that is right on channel.

Roland

seems to be al local problem, here in Münster I can't see anything, see attachment

[dk8cb]

A strange bitrate change!
I had left channel only for a moment.

Roland

[dk8cb]

@ tacitus-ms,

If you don't store your screenshots as .bmp but as .png, there is no need to zip them because then they are already small enough.

Roland

[dk8cb]

Hi,

here is my report.

Will go to bed now.

73,

Roland

[lx1nw]

Report from last night. I don't know whether the dropouts in last section are real or miscalculations of the Dream Software.

Regards,

Michel

[lx1nw]

IR @ start of DRM transmissions

[lx1nw]

IR @ end of transmission

[lx1nw]

2 last remarks:

the dropouts in 16-QAM could also result from my Laptop trying to fall into sleep or some other strange MS behaviour

the groundwave was always present at my location. It was interesting to notice how the skywave signals grew and shrinked and influenced the shape of the spectrum which was really badly distorted.

Regards,

Michel

[FritzWue]

Hello Michel,

similar results here, so your setup seems to be o.k..
99.0% decoded audio during the interval from 01:00 to 02:57 UTC.
I had a good sleep last night! :D

[simone]

Hi all,
good results from 0100-0130, and in the last hour with the low bitrate, see attachment
73, Simone

@Michel: Could you please let us know your real coordinates, those are Frankfurt/Germany ;)

[lx1nw]

Sorry, I didn't pay attention to the location details:

49° 35' N 6° 7' E

Here are the reception results from my second setzup (40cm passive indoor loop, AoR 7030, DRMSWR), same location.

Michel

[jimbo]

For the person who asked about the time between 0058-0059, yes there was a break of transmission for about 10 seconds.

And - around 0650 UTC this morning, the presenter announced that 1440 kHz will be in DRM at:

0800-1700 UTC
0000-0350 UTC

starting tomorrow

Some more checks for you all. I hope to get receiving equipment very soon.

Happy New Year!

[DigiBC]

Hi!

Attached are my results of last night: Much better than my experiences two days ago.

Since I was too tired to stay awake I have no idea how the reception "felt" like.

Regards - Jens

[carknue]

Hi all,

here is my complete report from last night. Only Dream results, because my DRM PIII 933 can not run Dream with many open Plot windows and DRM SWR in parallel anymore. But the PIII is the only PC that does not produce any noise or strange carriers around the airwaves, so I need to use that for DRM.

I also had the strange dropouts in the QAM16 transmission at the end. But I don't know what happend, because I was already sleeping at that time. But especilly the reception in the long middle part was very stable as you can see. The problem last night were more interferences on 1440 than too long IR.

I wonder why they want to stop between 3:50 and 7:00 UTC?

[lx1nw]

Hi,

DRM mode changes causes the exciter to mute it's output for about 13 seconds. This is also +- the time the receiver needs to regain synchronisation and fill the interleaver's memory. As you may have noticed, mode change occures at 0100 UTC (CR=0.6 -> CR=0.5) and 0300 UTC (64-QAM -> 16-QAM).

Happy New Year 2005

Michel

[tradio99]

last night DReaM results 1-4 UTC - CDA 10%
***
wish you in Y`2005 good DX, SNR at least 30dB, CDA-100% and NO dropouts!

[dk8cb]

Originally posted by carknue
But the PIII is the only PC that does not produce any noise or strange carriers around the airwaves, so I need to use that for DRM.

Hi Carsten,

have you tried to use an additional line filter ahead of the power supply of the other PC? Very effective!
Of course, you should also put a common mode choke on each audio cable, perhaps also on network cables. If this is not possible, because the connectors are too large to stick them through a ferrite core, you may also use an open "E" shaped ferrite core and after winding the cables on it, closing the "E" with the second half of the core and fixing it with a cable tie. Epcos "E"-cores can be bought from Buerklin (http://www.buerklin.com). Use those with N27 material and no air gap on the centre bar and put on as many windings as physically possible.

In case, there is direct radiation from the PC, it is important that the PC's case does not have a window in it (as is often used by "case-modders") and that ALL screws of the case are used and that they are securely tightened.

Roland

[radiomann]

Here's last nights report, only 53% i think due to some interferance from somewhere? I picked it up about 9pm (ish) around 1445khz and never got rid of it.

Paul

[carknue]

Roland, belive me, I tried everything to make my 2.6 GHz PC free of HF noise. I use a special double shielded and with a ferrit core at each side power cable. Special power filters and fit all other cables in and from the PC with ferrit cores. It reduced the noise noticable but there is still quite a lot a rest QRM from that PC on 15, 17, 21 and 25 MHz. The main problem maybe, that it is a complete vanless PC that makes absolute no audible noise. So it makes more HF noise ;-) But the PIII runs rock stable with the DRM Software Radio. CPU usage is only 30 percent. With mp3 recording it goes up to 55 percent. Dream requires in standart settings 60 percent after opening some additional windows it raises up to 80 percent. So no power for recordings or DRM Software. Maybe I will see if I can upgrade the CPU.

[DRM-Fan]

Carknue have you got 512MB or more of RAM ? Also the less progs running in the taskbar the better. I can run both Dream and the SWR radio together no problem on my 2.4Ghz Cel PC

Make sure you have a good amount of HDD space also at least a 3rd free

[johnn]

In addition to the high power carrier (Saudi Arabia?), there has been one on 1442khz. I thought it was generated internally.
My reception 30/12 was good at 18.3kps, but my impulse response was poorer than Rolands, & I am grateful for his screenshot.
Finally, why isn't DRM reception in Gernany "good" at night from 1440 where there is a ground wave?

[radiomann]

While I await RTL to switch to DRM may I wish you all a Happy New Year, and lets look forward to some great DRM listening.

Paul

[DRM-Fan]

Originally posted by radiomann
While I await RTL to switch to DRM may I wish you all a Happy New Year, and lets look forward to some great DRM listening.

Paul

Thanks Paul and you and everyone else who reads and posts on this forum...

(Not too happy for those poor people in Asia of course, terrible...)

Regards
Dave

[radiomann]

No that is sad news, I really feel for those people, I have given a donation which hopefully will help but money can't replace people.
They are in my thoughts and prayers.

Paul

Originally posted by DRM-Fan


Thanks Paul and you and everyone else who reads and posts on this forum...

(Not too happy for those poor people in Asia of course, terrible...)

Regards
Dave

[FritzWue]

..receiver up and running...
A happy new year everybody!
I'm gone to bed. :D

[radiomann]

Goodnight Fritz... Happy New Year mate

[carknue]

Happy new year to everybody!

Frank Sinatra is on in DRM p-stereo with a proper 25 dB. Good condition tonight.

[radiomann]

Now Diana Ross, but many dropouts for me

Happy New Year Carsten

[radiomann]

Got to say that sounds excellent, I wish I new someone who could sort out an antenna for me, but quite pleased with what I have achieved.

Paul

[carknue]

Still perfect reception here. Not a single dropout so far at 26 dB. Only the atomic reactor in our basement was running for 20 seconds and destroyed every signal.

[DRM-Fan]

Originally posted by radiomann
Got to say that sounds excellent, I wish I new someone who could sort out an antenna for me, but quite pleased with what I have achieved.

Paul

I've only a 20m long wire, you should be ok'ish though you get a lot of local interference I think ? I would use my Terk MW loop but the Elecktor does'nt seem to work with it

Do you or can you use the Dream s/w and or the DRM s/w radio with your winradio ?

[carknue]

Hmm, they have the same schedule as last night. At 0:58 they dropped down to 15 kbps mono w/o SBR.

Paul, what about a Wellbrook loop?

[radiomann]

I don't know to be honest, I dabble in radio but not really got a clue about antenna's.

Paul

Originally posted by DRM-Fan


I've only a 20m long wire, you should be ok'ish though you get a lot of local interference I think ? I would use my Terk MW loop but the Elecktor does'nt seem to work with it

Do you or can you use the Dream s/w and or the DRM s/w radio with your winradio ?

[DigiBC]

A happy new year to everyone! :) :) :)

Very good reception tonight!
Proper signal strength and SNR, no drop outs yet.

That's a quite good start into the new DRM year. :)

Oh no! No need to change the mode down to 15.2 kbps now... :(

Regards - Jens

[radiomann]

I am looking in to a Wellbrook, maybe later this year.

Paul

Originally posted by carknue
Hmm, they have the same schedule as last night. At 0:58 they dropped down to 15 kbps mono w/o SBR.

Paul, what about a Wellbrook loop?

[carknue]

Paul, I move soon into a new flat and already made there some DRM reception tests. First I used only the wire that is shipped with the digital World Traveller. With that antenna I was not able to receive some audio on 1296 khz. There where lots of local interferences. Next day I tried my wellbrook loop and everything worked fine. These loops are really magic, but quite expensive unfortunately.

[radiomann]

Thanks for the advice, I will look into it soon.

Paul


Originally posted by carknue
Paul, I move soon into a new flat and already made there some DRM reception tests. First I used only the wire that is shipped with the digital World Traveller. With that antenna I was not able to receive some audio on 1296 khz. There where lots of local interferences. Next day I tried my wellbrook loop and everything worked fine. These loops are really magic, but quite expensive unfortunately.

[carknue]

The error protection is really a bit oversized for a solid 28 dB....but the sound quality is still an improvment against AM. No hiss, no distortions and no Belgrad in the background.

[radiomann]

To me the sound quality is good even @ 15.2. Not so many dropouts now either, why not try 17.4?

Paul

[radiomann]

I guess at 8am - 5pm the Uk won't get much reception?

Paul

[carknue]

15.32 kbps Mode B at 9khz is equal to 17.4 kbps Mode B at 10 khz in error protection level. On medium wave there is 1 khz less bandwidth. 18.3 is equal to 20.9 kbps wit lower error protection.

[johnn]

My report for tonight 0030 - 0130. Better & better.

[radiomann]

I wondered why it sounded like 6095, in the future what will be the highest bitrate radio could use?


Originally posted by carknue
15.32 kbps Mode B at 9khz is equal to 17.4 kbps Mode B at 10 khz in error protection level. On medium wave there is 1 khz less bandwidth. 18.3 is equal to 20.9 kbps wit lower error protection.

[DigiBC]

I'd agree that the sound is a little better than AM but not good enough for the "ordinary" listener.

Signal strength and SNR had been a bit higher one hour ago but still no dropouts so far.

Regards - Jens

[carknue]

Surely, SBR is a must for a music program.

So we have the third night in a row with good reception. Still mostly above 27 dB here. The bad results from the first two nights have not been repeated. That looks promissing. If they could control the sky wave a little more like 1296 and 1611 khz, 19.9 kbps p-stereo mode A should be possible in future at night time. Or 18.3 Mode B mono or even p-stereo.

[radiomann]

Got to agree even with my poor Long wire, I seem to be getting good results, the first half hour a bit shaky. But these are tests early days yet on this frequency.

Paul

Originally posted by carknue
Surely, SBR is a must for a music program.

So we have the third night in a row with good reception. Still mostly above 27 dB here. The bad results from the first two nights have not been repeated. That looks promissing. If they could control the sky wave a little more like 1296 and 1611 khz, 19.9 kbps p-stereo mode A should be possible in future at night time. Or 18.3 Mode B mono or even p-stereo.

[radiomann]

A screenshot, very solid even for me, you guys must be breaking records?

Paul

[DigiBC]

You're absolutely right, Carsten.

I'm curious what mode they will use during daytime. Bit rates of more than 23 kbps should work fine for ground wave propagation.

@Paul
Don't expect your WiNRADiO to break SNR records, but I'm sure you'll achieve very good results.

Good night - Jens

[carknue]

Last ten minutes signal got weaker here and SNR dropped down two 20-23 dB as you can see in Dreams history graph. But it seems to improve again. But still no dropouts.

[radiomann]

Hi Jens,
I don't expect to break any records, why won't Winradio go above 20-23?

Paul

Originally posted by DigiBC
You're absolutely right, Carsten.

I'm curious what mode they will use during daytime. Bit rates of more than 23 kbps should work fine for ground wave propagation.

@Paul
Don't expect your WiNRADiO to break SNR records, but I'm sure you'll achieve very good results.

Good night - Jens

[radiomann]

12.7kbps now, very tinny.

Paul

[DigiBC]

The SNR dropped during the last 40 Minutes so the lower bit rate is helpful.

@Paul
That's not an easy question. According to the WR-G303 series specifications the important phase noise should be low enough.
But there seem to be other problems: An unmodulated AM carrier is always surrounded by a strange noise floor and there are peaks 1 kHz away from the center (as if the signal is distorted). I would be very surprised if that behavior wouldn't influence QAM signals too...

Now I'll go to bed, so good night again.

Jens

[carknue]

SNR is still into the mid twenties here. 15.2 would be low enough, I think. Now its close to telephone quality.

[carknue]

Here is my log. Perfect nearly all the time. Again these strange dropouts during the QAM 16 transmission in the last hour. I could not hear them. Maybe I already fell asleep or a bug in Dream? Only 4 hours then the daylight show beginns.

[simone]

Hi all,
that was a great start into the New Year, my best results so far, using the Sony SW 7600G and built-in ferrite antenna.
Interestingly only DReaM users get these dips in the last hour.
Happy New Year to all!
Simone

[FritzWue]

After comparing the graphs from the night before I changed my MLC number of iterations setting from 1 to 2 in DREAM. Obviously this makes the interruptions look smoother.
Last night there were very good conditions, BBC on 1296kHz was perfect too.

[simone]

...and I had a second setup with the loop antenna and FRG100 running, see comparison attached
73, Simone

[simone]

...and finally a capture of the screen, the upper DRMSWR window and DReaM windows are with the portable Sony/ferrite antenna, the other DRMSWR window is using the FRG100/loop.
IR was much better than the nights before
@Paul: For the price of a Wellbbrook you can get a couple of used portable Sony´s I guess :)
73, Simone

[df9rb]

Here a short report from 1:15 to 1:30 this night
At 08:00 this morning Drm transmission started.
Signal S7 in south east Germany, only one single nice
impulse in impulse respons, no drop outs in the first
30 minutes,

Bernd, DF9RB

[carknue]

Signal between S7 and S9 here in Frankfurt. Around 20 dB. narrow Impulse response, so Mode A would be better for a higher bitrate. But lightning impluses from light switches etc. cause short dropouts.

[Baldo34]

Hi all,
excellent signal near Kassel with SNR up to 24.0 dB, which is very high for Winradio.
See screenhot.
73, Klaus

[Per]

Hi,

Started the new year by listening to RTL Radio 1440. Time: 08:35-08:55 UTC.
Quite good SNR at the start, 16 dB! The audio level is a little bit low, I think.

[carknue]

What about Mode A? Dream calculates only 1.5 ms delay.

[DigiBC]

Hi!

Excellent signal! :)

Even my "Satellit 700" with ferrite rod reaches a constant SNR above 20 dB.

18.3 kbps sound not too bad, but Carsten is right, mode A and "near FM quality" should be possible without much loss in range!

Regards - Jens

[df9rb]

Quite good until 09:10 UT, signal then S0 in south east Germany.

Bernd, DF9RB

[carknue]

SNR between 19 and 20 dB here. I would suggest same settings as BBC on 1296 khz Mode A with 19.9 kbps but p-stereo. For a higher bitrate, the SNR would be too low. Signal around S8 here.

[Carl]

Hi all !
Excellent reception on 1440 here on west coast of Sweden,58,17/11,27, between 09.15 to 09.40.
S/N steady around 18-20 dB. At 09.40 first drop-outs started.Audio OK down to 13,5dB S/N !

At present : Digital World Traveler,8m "wet string",ATU,Acer lap-top with analog PSU (!).
Had to chase every possible and not so possible interference sources as "low energy lamps",alarm clock with digital display etc. etc. Cleaning up the close envirement when it comes to electric interference pays in S/N ....

BR, Carl , SM6HYG.

[carknue]

Yep, now Mode A with 19.6 kbps p-stereo. Audio bandwidth up to 14 khz that sounds really ok. Only hopping that my SNR will not decrease anymore. Around 19 dB. But surely I'm at the edge of main coverage area. Not really in main antenna pattern.

[simone]

Hi all,
a very weak signal now, SNR has dropped, only 8dB, no more audio decoding :(
73, Simone

[carknue]

Still 18-19 dB here and no audio dropouts, unless there comes a local switing impulse.

[DigiBC]

Strange: Now at 19.6 kbps my WiNRADiO DRM PlugIn achieves a 1 dB better SNR than before... :confused:
I get stable 23 dB and no single dropout.

From my point of view they could raise the bit rate even more. (I'm only about 120 km away from the transmitter.)

Regards - Jens