View Full Version : CVC - Voz Crista - 17660kHz from Santiago
jamesserpell
27-03-2006, 17:15
CVC is pleased to announce an extension of its regular daily transmissions in Portuguese from Santiago targeting Brazil, on a new frequency.
Time: 1800-2000 UTC
Frequency: 17660kHz
Power: 15kW
Broadcaster: Voz Crista
Language: Portuguese
Bearing: 45 deg
Target: Brazil
DRM technical parameters will vary
Reports and comments welcome here as always
Many thanks
James
Hi James, Mathias and all,
The DRM started about 1911 UTC. As you can see from the log, it became better and better the later in the evening it got. Quite a lot of uninterrupted decoded audio during the last half hour.
73
Terje
Telspace
27-03-2006, 20:09
some recording. quite good.
Denis
mathias_s
28-03-2006, 15:40
Hi Denis!
Good to hear from you again. I looked at your post and at Terjes too, and I don't understand why are you not getting a higher Correctly Decoded Audio. Has something changed since some time ago? I remember you had a very good signal from us for some time ago; with SNR: 12 db you had 100% of audio.
Mathias
Hi,
The band was open in the beginning. The strong AM station on 17660 left just when the DRM stream came on the air at 18 UTC. My log starts at 1840 UT, because I was listenig around in the band in the beginning. From 19 UT there was mostly un-interrupted decoded audio up until the end. The break at 1910 UT was a test. Unfortunately there was zero sound during the change from 14.76 to 16.08 kbps.
Terje
Telspace
28-03-2006, 20:43
Hi Mathias,
When I listen to the broadcast using Dream software, SYNC and DATA leds are always green. AUDIO led flahes several times per minute, but sound is not always affected, I can listen clearly to the program without cuts for a 10-15 minutes. Strange in fact.
I change antenna, using now the Wellbrook ALA1530S. The only improvement is a more stable SNR, but still in the range of 11-13 dB. I have higher SNR values on 17800 kHz from Sines (DW), that from Santiago.... Antenna seems working OK, since reception on 6095 and 7240 was possible the other night. When I made some tests in Europe last December and January, I was listening everyday RMC on 6175 Khz everyday with an average of SNR of 16-20 dB. Tomorrow I will be using the Digital World Traveller receiver. The S Meter of the Yaesu FT817 is always at S++. reception seems better in Switzerland that in Brazil....
We keep in touch.
Denis
Why CVC use protection level 1 with DRM Mode A, which is only for medium and long wave? For short wave better is DRM mode B or C, especially above 13 MHz . I'm having a lot of broken receive from CVC.
reception report of today
Hi all,
Quite good in Switzerland tonight. Yes, perhaps Mode B would be even better. Got 1 GB wav sound this evening. Quite heavy QSB at times.
Terje
Telspace
29-03-2006, 21:45
Hi,
Made a test today with the DWT receiver. Much worst. Tomorrow I'll switch to the Yaesu FT817 and mixer.
Hi all,
quite good the last hour.
Signal between 30 and 100 µV, DRM center frequency 300 Hz higher compared
to other DRM stations!!!! (TX-OFFSET????)
Bernd, DF9RB
Telspace
30-03-2006, 20:06
Mathias,
Quite good today.
Definitly no 16.0 kbps working. (first 20 minutes)
I changed computer and sound card. On your side, have you made some changes ?
Denis
Hi Mathias and all,
Really crazy conditions tonight. S1 and nothing for a long time in the beginning; record S7 - S8 during the last half hour. Strongest signal recorded so far here. But SNR is still very low... Wonder why. And why does not Mode B work? Puzzling.
Terje
mathias_s
31-03-2006, 13:48
Hi all,
Some of you are asking why we don't use Mode B or why it doesn't work; well Mode B does work, but the maximum bitrate we can get is 11640 bits/s, and that is with 16 QAM modulation. 64 QAM is too much for our TX, we have tested it and no audio is decoded. So, the best quality we have reached until now is with Mode A, 14760 bits/s, 16 QAM.
Answer to another question: we haven't done any big changes lately, but between the 6th of february and the 9th of march, because of a failure on our antenna, we used an another antenna with a different array, but with the same bearing: 45 deg. I don't know if this made some big diference.
The low SNR is because we haven't been able to get a better SNR on our transmission. I also get 13dB on my reciver here at the site.
Thanks for all you reports!
Mathias
Hi Mathias and all,
The Space Weather did not turn up in your favour tonight. My S-meter hovered around S3 all through the transmission. S4 decodes the audio or S3 - S5 with Fading works rather OK too. Oh well, it can't be great everyday over such a distance.
Noticed a break at 1930 UT when the label "Portuguese" suddenly changed to "Spanish" but otherwise the configuration was the same.
Best regards,
Terje
Here is a comparison report obtained with both Dream and DRM-Software.
Contrary to what the result suggests, audio output from the DRMSW was a lot better on the DRMSW although the MSC indicator was red for most of the time. Nevertheless, audio could be heard. Not so using Dream, which delivered only occasional chunks of audio.
It looks as if the codec incorporated in the DRMSW can still decode something even in case of an invalid CRC.
Roland
Hi,
The last 45 minutes were almost perfect. A slow start with S2 then the S-meter climbed steadily. Peaked at S8 (65 dBµV at the antenna terminal) about 15 minutes before QRT.
Terje
Quite good for some periods.
Bernd, DF9RB
Hallo Mathias and all.
Very bad propagation in evning for strong AURORA level 10, but low signal from start . after 60 min. signal go up from S6 to S9 to close down .
Hi all,
Today was no good at my location. The S-meter did not budge from zero. At 1940 UT I left the receiver unattended. Solar Flux is 100 and K=3, which suggests bad conditions. With the external DC power supply to the FRG 7700 I got some sound even that the S.meter stood on zero; normally the decoding starts between S2 - S3 (15-19 dBµV into the FRG 7700 antenna jack).
Terje
PS: My fault; DX / LOC was in "LOC" position. I'd be happy if you disregard this entry totally. Better luck tonight... :o
Hi,
Nothing - except for a trace of something at 1836 UTC...
Terje
Hallo Mathias and all.
Propagation was not so good this evning ,last 10min. of transmission is best .
Hi all,
The beginning was weak, second half picked up and became quite good, actually.
Terje
Telspace
07-04-2006, 20:06
Hi all,
Good, bad, good.
Denis
Hi all,
Sound in the beginning for a while, then the last 20 minutes were quite enjoyable. However, the Channel Impulse Response is rather flat and blurred.
Terje
Telspace
10-04-2006, 20:03
Hi all,
Almost perfect.
Denis
Hi,
The sun sets later and later and Voz' signal gets stronger later and later in the evening... Not much here except 10 minutes at the end.
Terje
Hi Mathias and all.
Signal this evning up from S3 to S7-S9 in 10min. so fading down again to S5 and noise.
mathias_s
11-04-2006, 16:43
Hi Denis!
Good to see that our signal is being well received in Brazil! Any changes on your equipment?
Thanks for your reports!
Mathias
Telspace
11-04-2006, 20:17
Hi Mathias and all,
The only change is the sound card. Before I was using a notebook, now a desktop. Beside still using a modified Yaesu FT817ND and a Wellbrook antenna or a simple dipole.
Today, overall, it was good.
Denis
Hi Mathisa and all.
Propagation was very bad this evning , but signal come up last 10 min.
Hej Mathias, hi all,
Tonight was not a big success - :( whatever it could have been. At least Telspace gets it OK; that is the main thing. We at this end just have to be happy that some bits are coming down on us too :) . By the way, I noticed an interruption for a minute or two in the DRM stream around 1933 UTC. No idea what that was.
Best regards,
Terje
mathias_s
11-04-2006, 20:56
Hi Denis and all!
Changing to a desktop must have been the reason of the improvement in the reception. We have noticed we have better reception in desktops than in laptops, and Dream didn't work when we tried it on a laptop.
Well, it is good that you have good reception now!
Mathias
Telspace
12-04-2006, 20:05
Hi Mathias and all,
During the first 20 minutes, the average SNR was above 15 dB.
Beside, very close to perfection.
Am I the only listener in South America ?
Denis
Hi Mathias and all,
The first 20 minutes was a dead loss. Of course, I'm not in the target area, but it is interesting how far 15 kW can travel. The last 25 minutes were quite good with lots of decoded audio.
Terje
Hej Mathias and all.
Good signal from start S8 and good sound , but propagation very fast go down.
So 118 min. give CDA of 31%.
Telspace
13-04-2006, 20:08
Hi Mathias and all,
Average SNR was 1.5 dB lower today. Any reason ?
Otherwise today was very good, but a margin of one more dB would be appreciated.
Denis,
Hi,
Sometimes >S3 which is my threshold for sound, sometimes up to S4-5, but very little decoded audio. Used Dream for the 1800 - 1925 UTC segment, then changed to the DRM Software Radio 2.0.38 at 1926-1954 UTC. Seems to be more recovered audio from the latter, but a terrible "bathroom" echo effect is present when the audio is faint. Would be fun to run to computers in parallel and log both receivers at once.
Two logs, one for each receiver have been added.
73
Terje
Hej Mathias and Hi all.
Very bad DRM condition my log have 86min. but only CDA of 14% .
My S meter swing S5to S8 .This problem come from the sun .
See this page for solar wind.
http://sohowww.nascom.nasa.gov/
A weak signal and not much audio on this transmission.
Roland
Telspace
17-04-2006, 20:09
Hi All
Almost perfect today.
Denis
Hej Mathias and all.
Very bad DRM condition my log have 120min. but only CDA of 10% .
My S meter swing S5to S8 .:confused:
Hi,
At 1920 UT sound began coming, but the conditions were not favourable tonight. The last ten minutes were best...
Terje
mathias_s
18-04-2006, 19:44
Hi Denis,
We tried to make improvements on the transmitter, and we got more SNR, but currents on the transmitter were not ok, so we left it as before.
Mathias
Hi,
The conditions were messy today; the signal was strong at times, but with a lot of heavy Fading, which made things complicated. The Channel Impulse Response is very diffuse.
There was a break in the transmission for about ten minutes from 1926 UT.
Terje
mathias_s
19-04-2006, 16:42
Hi all,
From the 21st to the 27th of April we will do special transmissions for the NAB 2006 in Las Vegas. Durnig this period we will not be on the air on 17660khz for Brazil.
Mathias
CVC to NAB Las Vegas 21500kHz:
http://www.drmrx.org/forum/showthread.php?t=1386
Perfect ! Signal 59+
No difference between the TS850 and DRT1.
Bernd, DF9RB
Hi all,
great results tonight
Simone
Hi,
The best for a long time! :) My log covers the whole transmission.
Terje
Hej Mathias and all.
The best for a long time! my Smeter swing from S7 to S9+10db .
Very good propagation from SA. :)
Hi.
Log from this evning.
Hi all,
signal more than 20 dBs weaker today. Only a little bit of audio today.
For weak signals the TS850 is better than the DRT1.
Bernd, DF9RB
Hi Mathias and all,
Yesterday was better. Today was plagued with Fading. It now takes about an hour before the signal rises over my "critical" S3 to get any form of decoded audio. Towards the end of the transmission there was heavy QSB and the S-Meter showed S4-6. S6 is +11 dB compared to S3.
Terje
mathias_s
28-04-2006, 14:15
Hi all!
Today we will be back on this frequency. We will try with Mode C to see what happens. The last days on 17660 KHz (19-20 april), we were using another transmitter which gave better results, I think. So we will continue using that one.
Thanks for all reception reports!
Mathias
Telspace
28-04-2006, 18:14
Hi Mathias and all,
At present time (18:11 UTC), average SNR of 12,3 dB, S7 and audio mono 9,1 kpbs. Decoding perfect but audio quality quite low.
Send you complete report later on.
Denis
Hi Mathias,
Signal dropping in and out - 10/11 db on WinRadio 313i at 1810z
Using ALA1530 loop. World cup promo announcment -"hello Deutchland".
Signal gone(off?) 1817. Back on 1820 11/12db -98 db.
73,
Peterc g3ufi sussex UK
Telspace
28-04-2006, 20:23
Hi mathias and all,
As from today. S8 to S+.
Poor audio though.
Denis
Hi and welcome back :)
Lots of Fading tonight, and difficult to get any audio until 1925 UTC, when the signal rose a bit. On 17 MHz I need roughly the same S-meter reading (3+) to begin decoding. However with Mode C, the audio starts at 9-10 dB SNR instead of 12-13 dB for Mode A. Now we are waiting for Mode B....
Log enclosed.
Terje
No audio here when I tried. But the signal was too weak and when I increased the RF gain, the signal was swamped by receiver intermodulation products. I think I need to build a simple preselector.
Roland
mathias_s
03-05-2006, 14:49
Hi all!
On monday it was a holyday here, so there was no DRM transmissions.
Yesterday we had a transmitter problem, so we couldn't go on air.
I hope we will be on air today.
Mathias
Telspace
03-05-2006, 20:04
Hi Mathias and all,
from today.
Denis
Hi Mathias and all,
Congrats to back on-air. Well, the later in the evening it gets, the better the result. From 1915 UT on it was very good :)
And a personal best for CVC: 15 dB SNR.
Terje
Hi Mathias and all.
Her is my absulut best log from this transmitter.
Start from S5 and up to S9 for close down. Top propagation this evning.
:)
Hi All
Good propagation Down Under too - though CVC is always very, very weak here. I was able to decode some audio today.
Cheers, Chris
Telspace
04-05-2006, 20:04
Hi mathias and all,
Today's plot.
Denis
Hi all,
Not my day today - night...
Terje
Hi Mathias and all.
I have very problem from Radio Vatikan on freq. 17655Khz ,very strong S9 from start but I switch in my 8m vertical antenna and this was better for R. Vatikan go down from S9 to S6 . DRM signal S6 .
1900UTC close down R, Vatikan and DRM play 100% .
Very good .
:)
Hi,
Not good at all today. Usually I get a lot of decoded audio with the S-Meter showing S4 or more, however, today I hardly got any sound unless the S-meter peaked at S7 (and that was not often...)
Terje
Telspace
05-05-2006, 20:15
Hi,
Today's plot.
Denis
Telspace
05-05-2006, 20:16
Sorry, forgot the plot....
Hi.
Very problem from AM splatter from 17655 Khz.
Last 30min AM close down and signal up from S7 to S9 . I have best siganl from 8m vertical .
:confused:
Hi,
The later the better.... But not good at all here tonight.
Terje
Telspace
08-05-2006, 20:03
Hi,
Today's log,
Denis
Hi. Mathias
Today's log, very low signal from start but come up very fast to S9.
;)
Hi all,
good signal today! With fieldstrength
73s Bernd, DF9RB
Telspace
09-05-2006, 20:25
Hi all,
Today's log.
Denis
Hi,
Not so lucky today either, but it always gets better towards the end.... Hm, I guess a directional antenna with some gain would do the trick. ;)
Terje
Hi Terje,
you wrote: Hm, I guess a directional antenna with some gain would do the trick.
It would be nice if it would be so! I observe quite often this frequency but not the trace of a signal most days. On some days I can see reports from Sweden or from you but nothing was here in South East Germany. My HAM-yagi is perhaps 3 or 5 dBs better than a good standard SWL antenna but the influence of propagation is sometimes 20 dBs or more over a distance of 500 km between the receiving locations.
73s Bernd, DF9RB
Telspace
10-05-2006, 21:13
Hi,
Me never did not pick-up any signal today.
Denis
mathias_s
11-05-2006, 18:29
Dear all,
Yesterday we had a problem with a transmitter and another one was out of service, so it was not possible to broadcast DRM.
Today we are on air again.
Mathias
Hi all,
A late start (here) tonight, but a lot of (intermittent) sound. As usual now, the reception gets better the later in the evening it gets.
Terje
Hi all,
Two logs tonight. Had to cut for receiver adjustments. As usual it gets better towards the end. The last 20 minutes were possible to follow to 95%.
Terje
Hi Mathias and all.
Good signal from start today, but slow QSB down 3 S units after 50min.
So up again ,good sound last 30min.
:)
Telspace
12-05-2006, 20:14
Hi all,
Only half an hour. But very good.
Denis
It started to become very good shortly after I had started logging and it stayed that way.
Roland
After yesterday's great result, there was not a trace of a signal today. :(
Roland
Hi Roland and all,
There is no DRM transmission Saturdays and Sundays, that could have been the reason. :D
Terje
There is no DRM transmission Saturdays and Sundays, that could have been the reason. :D
Didn't know that. I looked at the drm-schedule in Dream and there it was. But the schedule has not been very accurate lately, I already noticed that.
Roland
Rather good reception with >99% of audio during my logging period but the transmitter's frequency was about 356 Hz too high.
Roland
Telspace
15-05-2006, 20:06
Hi to all,
Today's log
Denis
Hi,
Roller-coaster tonight. In the beginning there was decoded audiowith rather weak signal and QSB, but later when the signal strength improved, the sound did not improve. Many factors change on the way, probably. If we could have a try with Mode B instead...???
Terje
Hi all.
Her is todays log, best signal strength last 30min S9+10db .
:)
Hi all,
Can only repeat myself from 12th May: "As usual it gets better towards the end. The last 20 minutes were possible to follow to 95%." Same case here tonight.
Terje
Hi,
Well, as Terje wrote ""As usual it gets better towards the end". I just tuned in at the end of this transmission and managed to get the last two minutes of this program. But the signal was good and reception was, during the short time, perfect. I'd better give it a try a little earlier next time.
mitajohn
17-05-2006, 20:04
Hi all,
Can you believe it? I received this TX here, with a good result!
John.
Hi all.
Big suprise Mathias .
My log from last transmission is very good . I have 73min. and 90 % CDA .
Hi Mathias and all,
Whether the addition of a second 8 meter long antenna to the UN-UN made the difference is not possible to tell after just one session.
Anyway, tonight was one of the better logs, and I have a 30 min segment with recorded audio up until the end. As usual the reception improves here after dusk (tonight at 1930 UTC).
High S-meter readings too; towards the end the meter topped at S8 and record SNR as well.
Terje
Superb reception throughout.
SNR is low and seems to be better at the edges of the spectrum, see attached screenshot. The impulse response also looks rather weird for such a distance but perhaps this is a result of transequatorial propagation.
Roland
Hi,
Despite the messy conditions tonight on the whole quite a lot of decoded audio. As usual it is getting better and better until QRT.
Terje
Hi all.
This evning was grandioso, magnificent. No QRM no QSB only perfect stabil signal from start to close down . S meter was st.by on S9 to S9+10db.
:)
I could not tune in earlier, so here is only a half hour report. The slow start may be a result of my receiver heating up the quartz thermostate and thus moving frequency a bit too fast at the beginning. Again very good reception after that.
I think the good results are based on the good large-signal handling capabilities of this old but only recently modified receiver and its virtual lack of intermodulation products. I could not expect such a result on my other receiver, which is only a Sangean ATS-803A.
Roland
Perfect. Is it realy distance ~13.000 km ?
I also tried this frequency today. I was listening the whole 2 hours and could not hear any longer dropout. The graph looks much worse, as usual with DRMSWR. Red audio led but perfect audio.
mathias_s
18-05-2006, 20:40
Hi all!
Thanks for all your reports! I'm very happy to see that you can get us so well at so many places! 13000 km to Poland must be right.
Mathias
mitajohn
19-05-2006, 20:08
Hi all,
Another reception result from this far far away TX.
John.
Hi all.
My log from today is also very good . I have 118min. and 96 % CDA
Low signal from start but after 5min. up to S9.
:)
Hi mathias,
many dropouts in the middle part. But perfect in other parts.
Telspace
19-05-2006, 20:19
Hi all,
Perfect today.
Log annexed.
Denis
Hi,
The first (unattended) hour I had the DRM Software Radio running and the first part of the log is from that. However, when I came down 4 minutes before the hour, the DRMSR was playing 100% although the graph tells a different story.
The rest of the transmission was logged with Dream. The reception was like a dream too. One of the better evenings so far! I recorded 30 minutes of audio up until the end.
Terje
Excellent reception again. I was lying on the sofa and in the background music from South America was constantly playing out of the PC's speakers like from a local radio station. :)
Um bom promoção CVC!
Transmission started about a minute late and there was no audio during the first minute or so. I had the impression that someone was still fine-tuning the TX. Is that correct?
The log shows results from both Dream and DRMSWR.
Roland
Nearly perfect
Bernd, DF9RB
Telspace
22-05-2006, 20:04
Hi to all,
Perfect again.
Today's log
Denis
I could only tune in for the last 16 minutes. Reception was again very good. The two short dropouts were caused by local noise pulses.
There are considerable sidebands outside of the intended DRM spectrum on this transmission.
@ Mathias: Can you tell us something about the type and gain of the antenna used for this transmission?
Roland
Hi Mathias and all,
Two logs with a break to check what was going on on the adjacent channels. All India Radio was chewing into the upper DRM spectrum and made reception difficult, and I was further plagued by quick QSB. Not so good here tonight.
Terje
Hi all.
Log for today , strong signal S8/S9 only short brake for test of Vertical antenna, but dipole for 14 Mhz was best.
I must switch off very fast 1940 UTC for strong tunderstorm.
:)
mathias_s
23-05-2006, 13:53
Hi Roland and all!
The 19th we just started late with audio, that's all.
Mathias
mathias_s
23-05-2006, 15:04
Hi Roland and all!
The antenna we use for this transmission is a TCI model 611. The configuration is HR 2/4/1 and the gain is 19,4 dBi.
Mathias
Hi Mathias and all,
Could have been better. I enclose the second part of my log.
Terje
Hi all,
very good today. Signal around 100 µV on the HAM-Yagi. Waterfall spectrum (CVC.png) looks like a cloudy sky (with the signature continued outside the regular DRM spectrum). The center frequency still approx. 300 Hz to high.......
Bernd, DF9RB
Excellent again. Shortly before the end of transmission, there was a break in the transmitted signal at 19:56 UTC, see screenshot.
@ Mathias: Thanks for the info concerning the antenna. A gain of 19 dBi is not bad indeed.
Roland
Hi Mathias and all,
Like I said many times, the signal gets stronger later on in the evening and the last quarter of an hour became more and more free of QSB.
Terje
this signal is stronger than Radio Luxembourg on 7.295
:) Hi Mathias and all.
Log for today , strong signal S9 no QSB , very good propagation on all band today.
I start her 1830UTC for antenna job.
There were a few TX breaks today, otherwise reception was again very good apart from a few moments with local noise.
Roland
Hi all.
My log today is from start, first 24min . and last 31 min. from transmission , I swtich of for very bad and mystical propagation . My S-meter peak S8/S9 but only SNR 9db. I get return again to last 31min. and now S9 and SNR 13db.
:confused:
mathias_s
25-05-2006, 20:51
Hi Roland!
Good! What kind of antenna are you using? Have you a picture of your antenna?
Mathias
Good! What kind of antenna are you using? Have you a picture of your antenna?
If I were to take a picture of it, you might not even be able to see it, because it's such a thin wire. ;-)
It is a centre-fed (via a balun transformer) dipole which is mounted directly under the ridge of the roof. In fact it's two dipoles in parallel, one tuned to resonance on 7 MHz and one tuned to 14 MHz. Since the roof is not long enough to have room for an almost 20 m long wire when stretched in a straight line, I have zigzag-folded the ends of the longer dipole as a kind of capacitive end load. Using the 14 MHz dipole as a transmitting antenna for telegraphy transmission, I was already able to reach the US with as low as about 700 mW of RF power on several occasions a few years ago.
Technically, I am capable of putting about 150 Watts into it but then the fieldstrength at the place where I am operating the transmitter would exceed recommended levels, so I can't do it. Now, I only use it for reception.
The receiver used for DRM now is an old E403, jointly developed by Siemens and Rohde & Schwarz in the 70'ies and also sold as R&S EK049 then. It weighs about 40 kg and is not very energy efficient since it consumes about 120 Watts.
The previously used Sangean ATS-803A produces too much intermodulation distortion when tuned to your frequency since signal levels from 6 to 7 MHz where the antenna is in resonance, are very high in the evening here. I still have to build a tuned preselector for it.
Attached is a picture of the receiver shown tuned to your frequency.
Roland
Hi Mathias,
strange programme today for a while. Music dubbed over with interviews of people in spanish about Gary Chapman (in a portuguese programme). Was that intentional? It sounded more like an error by the audio engineers...
Roland
Apart from a TX break at 20:13 and a few local noise spikes, reception was again excellent. The log shows results from both software decoders.
Programme language was wrongly indicated as Spanish this time, see screenshot.
I have recorded the last 40 minutes as an MP3 file, just send me a note in case someone needs it for demonstrational purposes.
Roland
Hi all,
more drop outs today.
Bernd, DF9RB
Hi all,
a bit too weak in the first hour. Second hour was nearly perfect. I also got some local noise from neighbours, a couple of carriers every 30 khz....
Hi Mathias and all,
Changed my longwire to a 15 cm long Ferrite antenna placed 60 cm above ground and got perfect reception tonight. Unfortunately I came back home 15 minutes into the transmission. 100% Decoded Sound right through. Recorded 40 minutes of the programme. Thumbs up. IMD good-bye.
Terje
Hi Mathias and all.
Her is log from today. Low signal from start but after 30min up from S7 to S9.
:)
Hi all.
Propagation today was very bad from start only S4 and QSB to S0. I tune back to 17660 , 1930 UTC very good signal S8 S9 and SNR up to 17.5 Absolut record in my log.
:)
Hi Mathias and all,
Perfect except for the two TX breaks around 1909 UTC and 1919 UTC. After the first TX break the SNR climbed to unseen record SNR from Voz on this frequency. 1.3 GB wav available from the best reception here for a long time. Perhaps my 16 cm long antenna is not so bad after all! :) Solid reception with a record 17.5 dB SNR.
Terje
I made computer modelling of propagation from CVC. I pay attention on diffrent between simulation from 18UTC and 20 UTC.
I have one question for Mathias: What kind of antenna you are using for your transmissions? In my simulation it is horizontal yagi.
Hi Janucha,
look here (http://www.drmrx.org/forum/showthread.php?p=27886) for the type of antenna used.
Power should be around 25 kW.
Roland
Hi all,
No good conditions tonight, but quite OK anyway. Tonight I used a Hewlett Packard HP8640 as a Local Oscillator instead of the built-in VFO in the FRG7700.
The reception was better than the graph looks like. Therefore I need to explain a few things about tonight's session (there are comments in the log as well):
1818 UTC Late start (of the transmission, that is) :D
1830 UTC Changed from the 17 cm antenna to the 16 m Long Wire. No decoded audio with that antenna.
1840 UTC Changed back to the BBF17 (17 cm long antenna)
1856 UTC Or just before, an interruption in the DRM stream (I think)
1912 UTC Noticed that the BPF in Dream was unchecked.
1919 UTC A break in the transmission.
1931 UTC I unlocked the HP8640 and re-tuned the center frequency.
1937 UTC started a WAV file.
1958 UTC end of transmission.
Just for your information....
73
Terje
FritzWue
30-05-2006, 21:52
The signal made me break my 17kbps rule... :o
Fast amplitude fading, not much fieldstrength, low snr, but audio nearly all the time!
Had to widen my DREAM search window, the signal is about 320 to 330 Hz too high in frequency.
Hi Mathias and all,
Wow! Very strong signal into my 16 cm antenna tonight. Just great!
Terje
Hi all.
Log for this day. I have strong local line QRM from start but after switch over to 14Mhz dipole better for QRM
Hi,
Quite good tonight too, despite QSB at times. The 16 cm long ferrite antenna (home brew) works wonders. One problem: The transmission ended early.
Used a crystal oscillator for tonight's reception. A perfectly stable "VFO" ;)
A record SNR for Voz! >19 dB. Not bad at all for an unruly ionosphere.
SF:78 A:5 K:3
Terje
Hi,
From 19 UTC it became possible to hear CVC. Up till then there was incredible splatter from Spain on 17.595 MHz. This station with its saturated modulation (or overmodulated) covered the entire 17 MHz band with splatter :eek:
When it went off the air around 19 UT the signal from La Voz improved immensely.
Terje
Hi all.
Very terrible splatter from TX on 17.595Mhz up to 17.850Mhz.
So only ref. to Terje. But very stabil signal on S9 only small QSB 1840 UTC.
:)
Telspace
05-06-2006, 20:05
Hi all,
Very good again today.
Denis
Hi,
Started on the Long Wire with an Antenna Tuner. After the TX break I changed to the 16 cm Ferrite Antenna with the Antenna Tuner installed. After that: Perfect!
Terje
mitajohn
05-06-2006, 20:19
Hi all,
Quite good here, except of a problematic start.
John.
Not so good on the portable receiver, most likely because of the receiver's own intermodulation products.
Roland
Telspace
06-06-2006, 20:01
Hi all,
Today's report.
Denis
mitajohn
06-06-2006, 20:07
Hi all,
99.78% CDA tonight, a weak but stable signal.
John.
Hi all,
Lots of Aurora up north, but quite good reception after a bumpy start. At the very beginning I had some IMD and switched on 10 dB RF ATT, which cured it. Around 1820 there was a TX interruption for about 3 minutes. At 1911 UT I changed to the longwire just for fun, but had to swich back to the 16 cm long ferrite antenna 5 minutes later. All these tests just to compare results.
Terje
Hi all.
Very good start from SNR 12 and S6 up to S8 but after 60min very fast down to S2 . And problem was AURORA ,level 10. See my log.
mitajohn
07-06-2006, 19:58
Hi all,
Today's report.
John.
Hi,
Tonight's log. A delayed start, which was due to technical problems :p on the receiver side... On the whole very good except for a couple of TX-related problems.
Terje
Hi,
I think the conditions could have been better... but the second half of the transmission was quite good after all. Quite a lot of QSB tonight.
Terje
With the E403 receiver still out of service, I had to use the portable receiver which suffers from intermodulation distortion that swamps weak signals. Nevertheless, I got something and I guess it would again have been a perfect result on the other receiver.
Roland
Some audio interruptions towrds the end of the transmission
Bernd, DF9RB
mitajohn
09-06-2006, 20:03
Hi all,
Except the problematic log's start then nearly excellent until the end.
John.
Hi,
My log shows nothing for a long peroid up to 1850 UTC, but the rest was nothing to write home about either. :confused:
Terje
Not a perfect result on the ATS-803 due to intermodulation .
Roland
Hi Mathias and all,
A little bit shaky start, but aferwards it was quite good.
SF:74 A:4 K:0
Terje
Hi Mathias and all,
A little bit shaky start, but afterwards it was quite good in my QTH also.
From S6 up to S9. very stabile signal last 60min.
Hi,
Wow! Can it become much better than this?? :)
With a 16 cm long antenna? :D
Terje
SF:77 A:6 K:3
Hi Mathias and all.
This was a grate start from SNR15db direct and sound start. Best signal I have see. I have small problem 1845UTC for start of Vatikan Radio on 17655 Khz and DRM go down 2 S units . But 1915UTC go DRM up and no problem from 17655Kz.
:)
Great reception from the beginning of my logging to the end.
Roland
Hi,
My antenna is still 16 cm long (0.16 m according to DIN) and tonight's SNR record was noted as 19.74 dB. Sound from the very beginning. Very good despite somewhat unruly conditions.
Terje
Very good after 30 minutes. The tx SNR limit seems to be fixed, at least to around 20 dB.
mathias_s
16-06-2006, 14:42
Hi all,
Great results!!
On Wednesday the final tube failed, and we changed it. After that we got better SNR, with 16 KW. Yesterday I decreased the output power to 14 KW and SNR was even better.
Thanks for all reports!
Mathias
Hi Mathias,
I often wonder why the frequency of your TX is always about 300 Hz too high. Shouldn't the Telefunken modulator, which includes a synthesizer as we can read in the text message, be capable of better frequency accuracy?
Unfortunately, local thunderstorms limit today's result here quite a lot so far, see screenshot.
Also, audio balance is very much in favour of the left channel, there is almost nothing on the right channel here with both software decoders.
Roland
Hi Mathias,
The conditions tonight were not the best. I had much less signal from the antenna tonight compared to the previous evenings. A C-class flare might have something to do with the bad result, perhaps. Unfortunately just today with P-Stereo and all :rolleyes:
Got some sound; when it came through it sounded great compared to the 14 kbps, but on the other hand, I did not get any sound unless I had 15-17 dB SNR. That plus the -10 dB into the antenna compared to other days made it difficult.
Hope for better condx on Monday! :(
Terje
PS: Agree with Roland on the Stereo sound; see image enclosed.
mitajohn
16-06-2006, 20:09
Hi all,
A nearly excellent result for 45mins. The signal started very weak but got stronger towards the end. The stereo is a mono left channel.
John.
Here is today's report. Thunderstorm activity was high and decreased a bit over the course of transmission whereas signal strength also increased at the same time. Without the thunderstorm, the result would have been much much better.
Stereo balance still needs to be improved!
Roland
Same average signal strength like yesterday, but QAM 64 made it much more difficult today. But quite good for 40 minutes in the second part.
J had beatifully wheather in north Poland on today evening -blue sky and the red setting sun. In my opinion idea with 64-QAM transmiting for Europa isn't good. 16-QAM was quite better for long range. There are two logs from yesterday and today.
Telspace
19-06-2006, 20:03
Hi all,
Today's log.
Denis
I got only the last 13 minutes today since I was not at home before. During the first three minutes of my logging period, there were some dropouts due to the receiver still moving in frequency as long as the crystal oven had to heat up before it reached a sufficiently stable temperature.
Sound quality was quite good.
Roland
Hi all,
with 16QAM 12 dB SNR was ok for audio now around 15 dB are necessary with 64QAM.
Bernd, DF9RB
Hi,
Not exactly overwhelmed; was it the higher bitrate or just that the signal was not as strong as it used to be. The first hour was plagued by QRN from thunderstorms in the vincinity. Yes the sound was much better - when I got some... I'll try to edit the sound file tomorrow.
Terje
Hi,
Just a short comment: The signal is strong, up to 35 dBuV, but there is not a trace of sound? I'll be back later with a full report. :confused:
Sorry, this was the biggest surprise so far.... 0% decoded audio :confused:
Terje
PS: Oh, tnx Mitajohn! I thought my ears had gone deaf!
mitajohn
20-06-2006, 20:02
Hi all,
Very quiet tonight! Is anybody monitoring? No sound...
John.
Telspace
21-06-2006, 12:27
Hi to all,
Even here in Brazil, there was absolutly no sound. Coding was 21.0 kbps, but max SNR was 13.5 dB, far from the 16-17 dB requested with this coding speed.
Mathias was out of reach.
Denis
Telspace
21-06-2006, 20:10
Hi all,
Today's log.
Denis
Hi Mathias and all,
Interesting to see that Telspace got sound from the beginning, but here in Europe we did not hear much until the Mode was switched from B to A around 1837 (?) UTC.
Terje
Brendan1
22-06-2006, 18:26
This log is typical for me when trying to copy CVC: nil to zero. This goes to show what DRM and a good directional antenna can do to prevent reception off the lobes of the beam. I'm only around 8500 km from Santiago, but about 75 degrees off the beam.
The second hour is generally worse...:(
73's
Telspace
22-06-2006, 20:06
Hi to all,
Today's log.
Denis
Hi,
Quite a lot of QSB and the signal was a bit weak in the beginning. Just for fun I changed to the Long Wire Antenna for 7 minutes but the Ferrite Antenna is superior. The best signal strength was just before QRT, but the whole transmission was plagued by heavy Fading.
Terje
Great reception!
Mode A works very well at this bitrate even over such long distances.
First thing after I had come home was to tune the receiver to 17660 kHz where signal was strong and reception was great. The bitrate used would support a larger audio bandwidth than what was actually transmitted but I guess the satellite feed from Miami does not allow more.
I have recorded CVC's audio over my complete logging period. A television with the World Cup match between Brazil and Japan was running in the background at the studio as one could easily hear. ;)
Roland
mitajohn
23-06-2006, 20:06
Hi all,
A good reception until 19H38 when deep fading started. Really mode A works fine in long distances.
John.
Hi,
I was fiddling with a new receiver which I dare not to speak about... :D
This was not the modded FRG7700 .....
So please do not pay attention to the log except for the end.... when I was adjusting bits and pieces.... It was a CB receiver converted to 28 MHz and an up-mixer from 17.66 to 28 MHz. I'll come back to this one in a couple of days when I get a grip on the thing......
Terje
Telspace
27-06-2006, 20:03
Hi to all,
Today's log. Second hour was better.
Denis
Reception was quite good, however there were a few short dropouts from a distant thunderstorm. This caused the somewhat shaky audio frames plot.
There was a TX interruption at 19:22 UTC.
Audio bandwidth could be a lot larger at this bitrate.
Roland
Hi all,
I lost the beginning while trying out yet another receiver. But the sharp AM filter was only 6 kHz wide, therefore I had to change back to the FRG 7700.
There was a lot of static from thunderstorms 50 km away in the beginning, which may have hampered the reception as well. I also noticed that the signal from Voz suddely took a dive and remained very weak here between 1830 and 1900 UT roughly, but then it picked up again. The last hour was pretty good.
Terje
Hi all,
quite OK the last 30 minutes
Bernd
Telspace
28-06-2006, 20:02
Hi to all,
Today's log
Denis
mitajohn
28-06-2006, 20:03
Hi all,
A late log start but a not at all bad result.
John.
Hi all,
A late log with a new (old) receiver, the one from 23rd June. Quite good reception during the time I logged.
Terje
PS: This is not the FRG-7700
Signal was weak and there was not much audio during the first 70 minutes. Although the DRM software's audio indicator was often red as was Dream's MSC indicator, there was definitely more audio from the DRM software than from Dream. The comparison log does not reflect this.
Roland
Telspace
29-06-2006, 20:02
Hi to all,
Today's log.
Denis
mitajohn
29-06-2006, 20:02
Hi all,
A weak signal gave the attached result.
John.
FritzWue
29-06-2006, 20:23
Hi Mathias and all,
could not resist and connected the DRT1 to the T-antenna tonight.
The signal and CDA rate are quite good, the later the better here, see report, but the audio still is not yet "near FM" quality.
I attached a short zipped MP3 with 64kbps mono that fairly represents the sound and gives a good impression about the missing higher audio frequencies.
FritzWue
29-06-2006, 20:26
....seems as if the audio source is limited to about 9kHz, see "audio".
Sometimes there are short moments with enough audio distortion to show what probably is the possible bandwidth of the coder, about 13kHz, see "coder".
Hi,
Same RX as yesterday with the FRG 7700 in parallel. Even with only the FRG 7700 the signal never rose above S3,5 which should be compared to S6 - S8 which is "normal" here. Only fractions of sound during the last 30 minutes here.
Enclosed is today's meager result.
Terje
....seems as if the audio source is limited to about 9kHz.
Sometimes there are short moments with enough audio distortion to show what probably is the possible bandwidth of the coder, about 13kHz.
Hi all,
Looking at a picture taken of the Audio Spectrum from the Stereo transmission on 16th June seems to verify Fritz' theory about the audio quality being less wide than the coder capability.
Terje
Looking at a picture taken of the Audio Spectrum from the Stereo transmission on 16th June seems to verify Fritz' theory about the audio quality being less wide than the coder capability.
If you listen to the programme or even visit the website, you will note that the programme comes via satellite from a studio in Miami, Florida and as I have already written in a previous post, it is most likely the bandwidth of this satellite feed which is the limiting factor.
Roland
Nearly 100 % today
Bernd, DF9RB
Not bad with signal strength increasing over the course of my logging. There was one TX break but I forgot to write down the time when it occured, so I can't tell wether it was the large or the smaller dropout visible in my log.
Roland
Hi all,
Much better conditions tonight. Almost back to "normal" S-meter levels. I wasted the first half hour trying out a different 455 kHz output, but it was no good for DRM. "What you see is what you get" is not always true. :D
The log shows the bitrate to be 20.96 kbps, but at about 1920 UTC it had changed to 26.56 kbps. However, the sound was about the same as usual. But the last 25 minutes were something entirely different: > 15 kHz audio bandwidth. Very good sound. That was a big surprise. The audio spectrum is enclosed in the log.
Terje
mathias_s
03-07-2006, 14:03
Hi all!
Thanks for all reports! On Friday we tried to see what was the audio bandwidth problem, so we improved kbps but nothing happened. After that, we broadcast our Spanish program instead of the Portuguese one, and then noticed the quality was much better. You can see this on Terje’s post. Roland, you were right!
Mathias
mathias_s
03-07-2006, 14:07
Hi all,
This week we will do some works on our transmitter, so we will not broadcast DRM.
:(
Mathias
mathias_s
11-07-2006, 19:11
Hi all!!
Today we are on air again. We are running with another transmitter, but I hope it goes well.
Mathias
Now with the spanish programme being transmitted, audio is much better with an upper frequency limit of about 13 kHz, see screenshot.
Although a different transmitter is being used, the WMER plot shows the same characteristic pattern as on the other transmitter used before, namely a high value at the edges of the spectrum and a significantly lower value in the middle. I don't see this on other DRM transmissions.
Roland
Hi,
Better audio, but the conditions were not favourable. Strong signal and - bad result in regard to decoded audio. With S9 on this receiver and stable conditions it would have been perfect, even with the high bitrate.
Terje
And here is my report. I came home late just to find out that there is again a CVC DRM transmisssion but being too late, I was only able to catch the last 11 minutes. The programme ended two minutes earlier than scheduled.
Roland
its very bad today- strong signal, but audio is only 54%
Telspace
12-07-2006, 20:05
Today's log
Denis
Today, there was interference from an AM signal on 17655 kHz. I listened to the lower sideband of this transmission and it turned out to be Vatican Radio broadcasting the rosary at the time when I checked. This signal seems to be the third harmonic of a transmission carried out on 5885 kHz, which I am also able to receive. In theory, this unwanted signal could be generated by non-linearities in my receiver, but to rule this out, I checked at the third harmonic of another equally strong 5.8 MHz signal and I found nothing there. Thus the third harmonic of this Vatican Radio signal already seems to be generated by the TX, it is then radiated and reaches me via an ionospheric path. This is highly likely, since other 17 MHz signals from southern Europe were also strong tonight.
Signal strength of CVC's transmission increased over the course of logging.
A few seconds before I started logging, there was a TX break at 18:37 UTC. Shortly after, SNR went up for a moment. It seems that this is a clue for a better SNR and perhaps it should be investigated further, there may be unwanted RF feedback into the DRM encoder which somehow decreases SNR. Think of the encoder delay (TX break -> no RF -> no feedback ->higher SNR for the duration of the encoder delay)!
Despite the worse log, there were again fewer audible interruptions on the DRMSWR than there were on Dream.
Roland
Signal was rather weak and reception was only good for the last half hour today.
I had the impression that it had to become dark for a better signal despite the fact that most of the path will have been still in daylight.
Roland
No luck at all tonight. The propagation conditions looked no good either. And a lot of nearby thunderstorms could have added to the problems.
Terje
Perhaps somebody at the TX site is reading this:
Today, there are periods with no audio despite proper decoding of the MSC stream at the same time. It looks as if something seems to be wrong with the audio feed.
Roland
Shortly after I had written the post abobve, the problem disappeared.
Reception was quite good during part of the transmission with nearly continuous audio on the DRMSWR, especially during the last half hour.
At about 19:59 UTC audio was muted but transmission continued for about another two minutes. However, it seemed to me that there was still some audio in the background so I then pulled the speaker volume up and really, there was still distorted audio at low level. So it seems the audio muting circuit is far from perfect, perhaps it's just a transistor that pulls the signal to ground.
Roland
P.S. Time corrected after Terje's note.
Hi,
I think that the transistor up in the sky pulling the signal appr. 42 dB down messed up the reception at my place......... Whatever, the conditions were not favourable at all tonight. At 2059 UTC I could not trace one single bit or byte of CVC. Roland? The transmission ended long before that, eh? :D
Terje
Quite good for the course of my logging period, however, there were two TX interruptions with no signal.
Again, audio was muted only partially at the end of transmission and the first half minute or so of the 20:00 UTC news could still be followed with distorted audio after pulling volume up.
Roland
Need to look into my receiver configuration. Moved the 455 kHz IF output in the 2nd log. Unfortunately here I was plagued with severe QSB tonight.
Terje
Almost continuous audio on the DRMSW, intermittant audio on Dream, quite different from what one might think from looking at the logs.
Audio was at full volume until the end when the TX was switched off.
Roland
Telspace
19-07-2006, 12:45
Hi to all,
Not so good yesterday.
Here's the log.
Denis
mathias_s
19-07-2006, 13:28
Hi Roland and all,
First of all, thanks for all your comments! I will try to explain a few things. The 12th of July you wrote about an increase in the SNR, well, we were making adjustment, and one thing the DRMMOD can do is measure the feedback and then make a pre correction. When the measuring is made, there are some changes in the output power, and I think, in a moment there is only an AM signal. After this, there is no RF feedback to the encoder during the transmission.
The 14th of July there were some audio cuts, and that was because a connector had some problem which we didn’t noted, but after some time we did.
I have a question. You have said a couple of times that our frequency is not accurate, that it is 300 Hz too high. How can you note that? What are your measurements?
Thanks everybody!
Mathias
I have a question. You have said a couple of times that our frequency is not accurate, that it is 300 Hz too high. How can you note that? What are your measurements?
Hi Mathias,
that is very easy. I am using a receiver (30 years old Siemens E 403 equal to Rohde & Schwarz EK049) which is equipped with a crystal oven and which has very good frequency accuracy and stability.
The DRM decoder here has to lock onto the IF signal using its internal FAC loop. If the receiver is tuned properly, then the locking frequency of the signal which can be seen in Dream's evaluation window is always the same on all 9 or 10 kHz wide DRM transmissions except on your transmissions where it is about 300 Hz higher than usual. OK, it may drift within a few Hertz over a long period, but only due to the residual drift of the LC oscillator feeding the 30 kHz to 12 kHz down converter.
Others have also noticed that your frequency is about 300 Hz too high.
I don't understand this, since in my view, the frequency synthesizer in the DMOD2 (which you must be using since it is shown in your text messages) should have better frequency accuracy.
Are you perhaps using an external source?
Roland
Hi Mathias,
I had a look at the signal with a WR G313i, which is quite accurate (not using a downmixer), and measured your frequency, it appears to be 315Hz too high.
Simone
Hi Mathias,
another thing which is very peculiar about your transmission is the strange increase of the WMER at the edges of the transmitted spectrum, see attached screenshot. I only see this on your signal, it cannot be seen on other station's signals.
I wonder where it comes from, I think it should be regarded as a problem in the centre of the transmitter's frequency spectrum since SNR is also lower than on other transmissions.
I don't know the way by which you have made your Harris tube transmitters DRM-capable, whether you have created an inefficient SSB transmitter by just shifting the driver and final stage operating point to make it more linear or (more likely) whether you are using a PDM modulator and the phase / envelope method.
On the weekend, I visited a local TX site which is running a modified AM (PDM) transmitter (also using a DMOD2). I was told that they had succeeded in overcoming the distortion at the minimum of the RF envelope which was in part due to the limited frequency response of the AM PDM modulator by adding a bit of carrier to their signal. Their PDM modulator is sampling at a rate of 54 kHz which in practice allows just a little over 20 kHz AM bandwidth, good enough for AM but not really sufficient for the DRM phase / envelope technique which would work better with a modulator bandwidth of about 50 kHz. Adding the carrier plus some corrections accomplished via the DMOD2 solved the problem and the spectrum is well within the spectrum mask. SNR at the TX output was about 32 dB.
Perhaps an idea to try as well.
Roland
And here is today's report.
The slow start may be a result of the receiver still heating up its crystal oven shortly after I had switched on.
Audio was again insufficiently muted at the end.
Roland
Telspace
19-07-2006, 23:18
Hi Mathias and all,
Today's log
Denis
Hi Mathias and all,
it is very easy to compare the center frequency of a DRM transmission between DRM transmitters.
The Dream (DRM-) software displays the center frequency. The offset to the nominal 12 kHz depends on the frequency accuracy of the receiver including the DRM down mixer to 12 kHz a n d the frequency accuracy of the TX. In all cases I tried with transmitters in the same broadcasting band and the receiver tuned on the nominal frequency the
displayed DC frequency is nearly the same with only 1 or 2 Hz deviation - except CVC with a center frequency more than 300 Hz higher...... This can be compared even between transmitters on different broadcasting bands if the receiver has a single reference oscillator used for the frequency range.
That means the DC frequency offset to 12 kHz of a station transmitting in the 13 MHz band is approx. 2.3 times higher compared to a station transmitting in the 6 Mhz band if the receiver is tuned to the nominal frequency and the TX is transmitting on the nominal frquency.
Bernd, DF9RB
Not so good today, in part due to local thunderstorms which caused interference.
The frequency was again too high as usual and audio was not muted totally at the end.
Roland
Telspace
21-07-2006, 21:39
Hi Mathias and all,
Well Roland, not so good also in South Brazil.
Lots of fading today.
Today's log during one hour only.
Denis,
skype: telspace2005
Condx bad today. Frequency Offset compared to other DRM stations 410 Hz!!!!
Bernd, DF9RB
Rather good in Munich today. Almost constant audio on the DRMSW despite the low percentage of decoded audio shown in the log.
I can confirm the large frequency offset posted by Bernd.
Roland
Today's result.
Frequency is still too high.
@ Mathias: Do you use the external 10 MHz reference input to the DMOD2 and if, what is feeding it?
Roland
mathias_s
27-07-2006, 19:40
Hi Roland,
We don't use an external 10 MHz reference input. We haven't had the possibility to work on this problem. Sorry.
Mathias
That's interesting: CVC's signal is only useable after local sunset, see report.
Was it solar noise that made the difference?
A much better SNR than on all previous days. What happened?
Roland
Telspace
31-07-2006, 20:10
Hi mathias and all,
Today's log. Not bad at all.
Regards,
Denis
Nothing received today. No transmission or no propagation?
I only get a strange but weak broadband interference signal all across the band, hopefully, it's not CVC's TX that produces it.
Roland
Telspace
02-08-2006, 20:08
Hi Mathias and all,
Today's log. Lots of fading this afternoon.
Regards,
Denis
I was only able to listen for the last 11 minutes. SNR was again low. Virtually constant audio on the DRMSWR which ran in parallel but which didn't log.
Roland
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