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carknue
15-05-2004, 12:11
I got here also sporadic E reception from France. Sometimes it is good enough for some seconds of audio.

MarkT
29-05-2004, 10:09
Hi Folks,

Strong sporadic E`s from N.W France this morning. Some good decoded audio as well. Sounds like the same rock track on a constant loop as I originally heard a few weeks ago.

MarkT
29-05-2004, 15:18
Hi all,

My second report from TDF DTech 25775 kHz this afternoon.

Baldo34
15-06-2004, 07:13
Hi all,
sporadic-E-reception on 25775 this morning, sometimes Audio.
See screenshot.
73, Klaus

MarkT
19-06-2004, 09:53
Hi all,

Another sporadic E opening to France yesterday afternoon.
Report not bad with ocassionaly good audio.

MarkT
23-06-2004, 18:35
Hi all,

Picking up strong sporadic E`s on 11 meter band from France just now 18.30 UTC.
While listening in to 25775 kHz I am receiving "pulsed DRM" noise on this freq every 2-3 seconds. Unfortunately I cannot get a software lock due to on/off duration.
Wondering if TDF DTech are doing some sort of test?

MarkT
26-06-2004, 20:03
Hi all,

Another nice opening to N.W France this evening.

Baldo34
02-08-2004, 18:37
Hi all,
again Sporadic-E reception from the TDF-station in Rennes this evening. See screenshot.
73, Klaus

CT1ADT
02-08-2004, 20:32
Hi all

I got here also sporadic E reception in Sines.

carknue
22-05-2005, 09:44
Sporadic E is back and also TDF Rennes in Germany ;)

Baldo34
22-05-2005, 10:25
Now 15 dB and audio.
See screenshot.
73, Klaus

MarkT
22-05-2005, 11:25
Hi all,

Picked up TDF-DTech this morning as well with good audio at times.

df8uo
22-05-2005, 11:27
Hi all,
quite good reception also here at my location. However strong fading.
73, Daniel

df8uo
22-05-2005, 12:19
And heres my result. Signal dissapeared 12h10
73, Daniel

dk8cb
22-05-2005, 12:39
Hi

triggered by Daniel's report, I gave it a try as well.

I can get the occasional station label but so far no audio. Fading is very strong.

Roland

dk8cb
22-05-2005, 12:57
And here is my report.

Much too weak for audio.

Roland

Bob
22-05-2005, 18:09
Hi,

After seeing today's reports I tried reception this afternoon and for the first time was able to get audio (although intermittent) but with a peak SNR of 19 dB.

regards
Bob

Baldo34
30-05-2005, 07:25
Hi all,
sometimes audio this morning with SNR up to 17 dB.
See screenshot.
73, Klaus

dk8cb
30-05-2005, 08:33
Occasional bits of early 70'ies rock music in Munich as well.

Roland

MarkT
01-06-2005, 18:15
Hi all,

Managed to catch a hours worth from DTech this afternoon via Sporadic E`s again.

dk8cb
02-06-2005, 10:08
Hi,

interesting, how summer conditions offer occasional reception on the 11 m band.

Also interesting to see, how the signal was received via two distinctive, equally strong paths for most of the time, see screenshot.

Update: Actually, these were not two paths but two transmitters operated in a same frequency network (SFN), see post below.

Roland

GRUSON
02-06-2005, 10:38
Hi Mark, Klaus, Roland, Daniel and all,

Thanks for reports about E Sporadic reception of our 25775kHz transmissions from Rennes (TDF DTECH: Direction Technique in Rennes / Britany). We are currently running an experimental SFN network with two transmitters so you are supposed to receive two transmissions with a delay of one millisecond between them.

We are running 100W transmitters into quarter or half wave antennas but one is located on a 100m high tower, the other one is a bit lower.

In TDF, we are also running higher power transmissions on 6175kHz from Issoudun.

Regards.

Jacques Gruson:)

df9rb
02-06-2005, 18:45
Hi,

I could also receive TDF via sporadic E today.
The two pulses can be seen clearly. Approximately 80 %
of time the pulses had the same hights. This shows that
the difference of the antenna hight has no big influence on
sporadic E propagattion. I added a short log and a screen shoot
in the zip-file.

Bernd, DF9RB

MarkT
02-06-2005, 19:41
Hi all,

Another E`s opening tonight to Rennes.
Two peaks visible here also on the impulse
response roughly 1mS apart.

df9rb
03-06-2005, 18:53
Hi all,

today for more than 2 hours stable via sporadic E.
In average the 2 nd impulse 1 ms later was weaker
today compared to the first. Does anybody know what
antenna is in use for what transmitter.

Bernd, DF9RB

MarkT
03-06-2005, 19:15
Hi all,

Very good results today Bernd, congratulations. A bit of a marathon session for me also from Rennes.
Reception was quite listenable considering
fluttering E`s with occasional audio breakup.

F6AJW
04-06-2005, 18:42
Hi Mark and Bernd,

i am using my home address...

Amazing to have such a long-duration reception, Bernd; very good also Mark!

One transmitter (100W with a 3CX 1500 class A) uses a half-wave antenna at 100m asl, the other transmitter is 100W also but solid-state and a quarter-wave antenna at 30m asl (not really sure, I will confirm this latter). Transmitters are about 6km away. In fact SFN is useless in E Sporadic, I think!

73.

Jacques

:)

Digger
07-07-2005, 12:31
Hi,

This morning I recorded TDF in Rennes for the very first time on 25775 kHz. The reception was at times quite good but with a few dropouts. Then suddenly just before 0900 UT the signal suddenly disappeared.

73's

Terje

GRUSON
08-07-2005, 08:50
Thank you Terje for this very first report of 25775kHz Rennes transmission via E sporadic from Switzerland.

73.

Jacques Gruson F6AJW

Digger
17-08-2005, 09:14
Salut Jaques,

Just read the note you wrote for 6175 kHz. Is 25775 kHz still going strong?

73 de
Terje

:confused:

GRUSON
17-08-2005, 13:18
Salut Terge,

Yes, we keep on transmitting on 25775kHz from Rennes (TDF R & D labs) on a regular basis.

But unfortunately, it's now a bit late for E Sporadic season...

73.

Jacques:)

FritzWue
25-08-2005, 22:38
Salut Jaques,

it's never too late. Here's a little midnight surprise.
TX frequency was abt. 30Hz too low.

MarkT
26-08-2005, 22:36
Originally posted by FritzWue
Salut Jaques,

it's never too late. Here's a little midnight surprise.
TX frequency was abt. 30Hz too low.

Hi all,

Here is a bit of midnight surprise as well.
Captured 35 minutes of D-Tech with very little decoded audio.

MarkT
27-08-2005, 12:09
Hi all,

Quite good reception this morning via E`s with nice audio quality (sounded just like a local FM station).

Digger
28-08-2005, 10:16
Salut all,

I let the PC run and had a look this morning. There was a small surprise, however very small ;)

(The antenna was not the active antenna, but an EH Star for 27 MHz.)

73s de

Terje

df9rb
28-08-2005, 12:08
Hi,

sporadic E now to Soth East Germany.

Bernd, DF9RB

Digger
29-08-2005, 07:49
Hi Bernd,

Interesting; I have logged the QRG all day, but nothing recorded so far at all. I'll leave the log running until this evening. At the time of writing the Ionogram from Belgium shows strong E activity, and there is a trace of DRM on 25775 kHz.

(29th Aug.: The trace of DRM mentioned got stronger yesterday in the afternoon. The receiver was left unattended and enclosed is a picture of the result.)

73s
Terje

GRUSON
30-08-2005, 10:53
Hi All,

A bit surprising!!!

We will start in the near future an other test transmission on 21765kHz from Paris with about 400W into a 3el vertical Yagi roughtly to Germany.

Regards / 73.

Jacques :confused:

Baldo34
30-08-2005, 12:37
Hi Jacques,
good reception on 25775 also in Central Germany on Aug 26 around 12:20 UTC.
73, Klaus

Digger
31-08-2005, 11:37
Originally posted by GRUSON


We will start in the near future an other test transmission on 21765kHz from Paris with about 400W into a 3el vertical Yagi roughtly to Germany.

Regards / 73.

Jacques :confused:


Salut Jacques,

Did you mean "25765 kHz"? My old friend Sixten SM5DAJ just North of Stockholm picked up a TDF signal on 25675 kHz at about 1030 UTC today 31st August.

Best 73s
Terje

GRUSON
31-08-2005, 13:13
Salut Terge,

Yes this is our test transmission on 25765kHz that was received in Sweden, congratulations! It will run until tomorrow morning but the sound is currently always the same (the same song in loop).

It could be interesting to know if you can receive DTECH Rennes on 25775 and TDF Meudon on 25765kHz at the same time and with which relative signal-strengh?

73.

Jacques

Sixten
31-08-2005, 14:28
Hallo all.
Her is picture from transmission at 1035UTC 050831.
Freq. 25765khz
I have sound short time for QSB and my S-meter peak max S3.
This time AURORA level 2.
Now is AURORA level 8 very poor propagations.



73 de SM5DAJ

GRUSON
31-08-2005, 16:45
Thanks for DX report, Sixten!

400W DRM into a 3el Yagi vertical to N.E from Meudon Tower near Paris 65m asl.

73.

Jacques Gruson F6AJW

Sixten
22-05-2006, 17:35
Hi Jacques,
good reception on 25765 in Sweden today via sporadic " E "

My S-meter peak S8/S9 in QSB max.

This is new station via sporadic " E " in my log. :)

F6AJW
22-05-2006, 20:42
Hi Sixten!

Congratulation for this first DX reception this year of our 25765 kHz transmission from Meudon near Paris, great!

Please have a look also to 25775 kHz from TDF / Rennes with 100W to a half-wave omni antenna. Could it work at the same time?

Reminder: some other transmissions are also done from London and Luxembourg.

73 / regards.

Jacques GRUSON F6AJW

dk8cb
07-07-2006, 07:46
A trace of a signal in Munich today. Even enough audio to understand "Merci à vous".

À votre service! :)

Roland

F6AJW
07-07-2006, 21:53
Merci Roland!!!

Best regards, 73!

Jacques F6AJW:)

Digger
07-07-2006, 22:09
Hi Jacques and all,

Yes, sighted here in Swisserol as well. No rock music, though....


Terje

simone
08-07-2006, 05:11
Salut Jacques,
not too bad yesterday.
Simone

FritzWue
07-07-2007, 18:13
Salut Jaques,
I hope this was identified correctly as your TX in Rennes.
That mode B 20 kHz wide signal is difficult to decode as the Flex-Radio software uses a fixed 10 kHz wide filter in DRM mode. Had to switch to wideband spectrum mode centered to 25769 kHz and DREAM to 6 kHz to see the entire signal. :)

Sixten
10-07-2007, 13:19
Salut Jacques,


Good signal today on 25775 Khz but not fan for 20Khz BW . My RX is only 10Khz BW.

GRUSON
10-07-2007, 14:55
Salut Fritz, Sixten and All,

Thanks for new reports on E sporadic propagation from our Rennes transmision; sorry, we are using 20 kHz bandwidth as we want to transmit two programmes at the same time. Fritz found out "TDF variétés" but there is an other one to discover... Guess what?

Meudon (near Paris) is no more transmitting on 25775 kHz .

Jacques

FritzWue
10-07-2007, 15:16
but there is an other one to discover... Guess what?

Salut Jaques,

yes, now I see! :eek:
I was so busy getting that B/20kHz signal into any filter that I totally missed that! :rolleyes:

simone
10-07-2007, 15:27
Salut Jacques,
what about using mode A on this transmission?
Simone

GRUSON
10-07-2007, 15:45
Salut Simone,

Yes it could be possible to use Mode A (higher bitrate available) on 26 MHz but the use of CPE / CME (Phase and Magnitude Corrections) would be mandatory; we have implemented this corrections in DReaM software but other people do not have it available for the moment.

Regards.

Jacques

Digger
10-07-2007, 17:06
It even spilled out over the EU borders this afternoon. :D
All I got was "French", "Pop Music" and E1F221.

Sixten
14-07-2007, 13:59
Salut Jacques.

After mod. of my IF amp. So play TDF Varie'te's ,log is 30min. Strong signal today via Sporadic " E ". Switch from 1 to 2 is ok also.

FritzWue
15-07-2007, 10:26
Today also strong sporadic E here, I can listen to both programmes.

FritzWue
15-07-2007, 10:43
...switching between both programmes. :cool:

Sixten
15-07-2007, 18:16
Hi all.

Today also strong sporadic E .

GRUSON
17-07-2007, 16:40
Thank you Simone, Fritz, Terje, Sixten and all for DX reports of our 25775 kHz transmission from Rennes. So you have got both programmes now, thanks for recording to Fritz!

Unfortunately, I have here in Paris no Sporadic E reception; London and Luxembourg transmitters are too cloose from me; may be some German transmissions would work? I will try in a few days (holidays) from South West of France near Spanish border where I have already received Crystal Palace on 25695 kHz (but in analog mode only).

Regards.

Jacques

Sixten
19-07-2007, 15:34
Hi all.

Very small part of signal via Es from TDF transmitter today.

Digger
20-07-2007, 10:56
Hi Jacques and all,

A taste of 25775 TDF Variétés and TDF Info in Stockholm caught with the Kchibo KK-DRM01 receiver. Next time I go to Stockholm I'll bring a "real" receiver. :D



Temporary location: Near Stockholm, Sweden, N59° 24.5' / E18° 00.8'
"Receiver": Kchibo KK-DRM01
Antenna: Built-in Telescopic
12 kHz connection: 12 meter shielded wire, 2 m wound on a ferrite ring
12 kHz amplifier: Battery operated, about 10 dB gain
PC: ACER Travel Mate 2480, battery operated when using Dream

Sixten
20-07-2007, 16:49
Hi Jacques and all,

Log 39min. but not so strong signal , only CDA 3% !!!!

Sixten
28-08-2007, 16:12
Hi Jacques and all, small parts of signal from Rennes today.

Per
29-08-2007, 18:36
Hi,

A ten minutes capture at 18:06 UTC, then the signal was more or less lost.