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chemclouds
10-07-2004, 03:07
Hello,
Beginning now, I will only use this thread as log updates for CBC.
Report not complete. I missed the last half. I have a question. It may get a little technical. I will ask later.
First half of DRM from CBC. 6140. Front End signal strength 20 db.
Why such a high S/N in the DRM signal ?
See Attachment
Chemcloud
chemclouds
10-07-2004, 03:11
Where did it go ?
Attachment below.
chemclouds
10-07-2004, 04:20
Hello,
Well, I have 44 minutes of it.
See attachment.
Chemclouds
chemclouds
10-07-2004, 17:16
Hello Ludo,
Not bad, not bad at all.
I listened to a good portion of the broadcast using a pair of AKG K240. Later I switched to a pair of KLIPSH KG 3. The highs were very clear the midrange also clear and clean.. The low frequency. What can I say? It sound good to me. Better than mono FM.
I liked it !! It would be nice to try Stereo.
See attachment,
Chemclouds
Hi Carl,
Thank you very much for tuning in. Reception looks very good! In which city do you live?
We are in stereo in Europe and hope that CBC will be able to offer stereo as well in the near future.
Thanks again for your report.
Ludo
chemclouds
11-07-2004, 00:06
Hello Ludo,
The town I live in is only on a local Map. However I live about 15 minutes east of Richmond, Virginia. USA . Three miles south of the Richmond International Airport.
Chemclouds
CBC 9800 Attachment below.
chemclouds
12-07-2004, 00:49
Hello,
You almost did it.
See attachment.
Chemclouds
chemclouds
13-07-2004, 00:04
Hello,
Seems like reception is improving.
chemclouds
13-07-2004, 02:13
Hello,
Not very good tonight.
chemclouds
14-07-2004, 00:06
Hello,
We had storm near here, during this broadcast
DRM cut right through it. Not bad.
See attachment.
Chemclouds
chemclouds
14-07-2004, 03:01
Hello,
I missed the first half.
Here it is.
chemclouds
15-07-2004, 00:11
Hello,
Here it is.
Chemclouds
chemclouds
16-07-2004, 00:13
Hello,
In the beginning there was a high frequency oscillation. I did not measure it. I will estimate it at about 10 to 12 KHZ. Next time I will measure it. The signal was very good this evening. What caused that oscillation ? It was not on my end.
Chemclouds
Hi all,
some good periods last night as interferences were not so bad, see attachment
73, Simone
chemclouds
18-07-2004, 00:06
Hello,
Thanks you Simone.
Well, I got a portion of it.
Not bad. What happened to TDPRadio today ? It wasn`t there at 2000. LUDO !!!
See Attachment
Chemclouds
chemclouds
18-07-2004, 02:04
Hello,
Man, this is bretty bad.
See Attachment.
Chemclouds
Hi all,
pretty good results in the last hour, when the frequency is not occupied by others here in Europe, see attachment
73, Simone
Hi Carl,
The broadcast to North America is Saturdays from 1600-1700 UTC on 11900 kHz and not at 2000 UTC on 9800 kHz. Since yesterday, it is followed on Saturdays starting at 1700 UTC by the Voice of the NASB, on the same frequency.
Ludo
Originally posted by chemclouds
What happened to TDPRadio today ? It wasn`t there at 2000. LUDO !!!
See Attachment
Chemclouds
chemclouds
19-07-2004, 00:00
Hello,
Now, this is more like it.
See Attachment.
Chemclouds
chemclouds
20-07-2004, 00:14
Hello,
Not bad this evening.
I missed the forst hour.
See attachment.
Chemclouds
chemclouds
20-07-2004, 02:10
Hello,
Not very good tonight.
see attach.
Chem
chemclouds
21-07-2004, 00:02
Hello,
I had a few drop outs this evening.
See attachment.
chemclouds
chemclouds
21-07-2004, 02:01
Hello,
Same as usual. Not very good.
See attachment.
Chemclouds
chemclouds
21-07-2004, 23:59
Hello,
Reception was a lot better this evening.
See attachment.
Chemclouds
chemclouds
22-07-2004, 04:08
Hello,
Here is a chart of about an hour of your transmision on this freq.
See Attachment.
Chemclouds
chemclouds
22-07-2004, 15:34
Hey Ludo,
My apology for the incorrect time and frequency of your transmission. I will be here at 1600-1700 UTC Saturday on 11900.
I like that music. It`s far out stuff. Can your broadcast be extended ? Say, about 2 hours ?
CBC, I request that you install or switch a stereo encoder in the circuit. That would be so cool !! Come on guys, how about it ?
Lets move forward with this stuff. My hair is turning gray !!
Thanks,
Chemclouds
chemclouds
22-07-2004, 22:41
Hello,
We have a thunder storm here, so I had to cut it a little short.
The reception was not bad though. Here is about 3 hrs. of data.
If storm passes quickly, I will upload the next transmission.
Thanks,
Chemclouds
chemclouds
23-07-2004, 21:17
Hello,
For the first few minutes everything was going fine and sudddenly your signal level dropped about 7db and began fluctuating +- 6 db. I stopped logging . I have been getting around 9 db of of solid signal in the past.
Here is about 1 hour of it.
Chemclouds
Hi chemclouds - thanks for posting all the reports. Looks like we are similarly distanced from RCI-Sackville. I'm in Toronto - 1230 kM away compared to your 1420kM. I'm impressed by the high success rate you are having compared to mine. I can go for hours with nothing more than a blip and, on the best of days and frequencies, no better than 40-50% audio decoded.
What are you using with the R75?
Here:
Ant - G5RV
RX - modified Radio Shack DX-394 with AGC mods including defeat
Converter - homebrew NE612 fed from before the 2nd IF filters with its own anti-image filter with 20kHz bandwidth
Software - DReaM 1.07
I tend to get better results on the higher frequencies and lower bit rates - MOI-Kuwait having the highest decoding result at 11.64kbps. Also think that defeating the AGC helps - the 2nd LO of the receiver seems to pull with varying IF gain.
Regards,
Tom
Has anybody else noticed that DRMcalc positions 6140kHz somewhere other than Sackville? In my case, it erroneously calaculates the distance as 6157km, bearing 299/50 versus the correct distance of 1231km, bearing 264/73. The frequency must be associated with a European location in DRMcalc.
Tom
chemclouds
24-07-2004, 02:11
Hello,
Tonight was one of the best signals that i have received on this freq. I had and maintained a 15 db signal. Then, suddenly within 30 minutes i began losing sync. still showing a good signal strength of 15 db. I would like to know why ? What is causing these drop outs when i am having a good signal level. Anyone with a answer ?
thanks,
See Attachment.
Tom,
I will get back with you shortly. Hang in there.
chemclouds
chemclouds
24-07-2004, 03:13
Hi Tom,
There are hundreds of variables that could explain your problem.
Like for example, how sensitive the receiver is. The noise figure in each stage. which includes the rf amp, mixer, if amps and etc. also the antenna, does it resonate at the proper frequeny. The direction of the antenna, and the height of it. there are probably other factors as well, that i can`t think of at the moment. Tom, i am not familiar with the DX-394. However, i have heard of it. I am using a NE602 as the mixer. that is basically the same that you are using. Mine is also homebrew. As far as the decoding software is concerned, i don`t use Dream I have tried it, but i do not like it. I use the DRM software Radio Merlin. It is so cool. Tom. if you have a schematic of the DX-394 upload it. I would like to see the tap point that was chosen for the Down-Mixer.
Thanks for the reply,
Carl
Hi Tom,
Maybe you can try to listen to TDPradio via Sackville on Saturdays from 1600-1700 UTC on 11900 kHz. We understand the signal is quite strong at that time so it might be a good test.
And Hi Carl,
Hope you can give it another listen today and note that right after TDPradio, starting at 1700 UTC also on 11900 kHz will be a broadcast from Voice of the NASB.
Ludo
chemclouds
24-07-2004, 12:41
Hey Ludo,
I will be here. 1600-1700 UTC on 11900 kHz.
Carl
chemclouds
24-07-2004, 17:04
Hey Ludo,
Here it is. Not perfect, but close to it. The quality was very good.
I am recording NASB now, and will upload it on it`s completion.
Carl
chemclouds
24-07-2004, 17:32
Hello,
I have no report for NASB. Seconds after uploading TDPradio we lost power here for about 22 minutes. Reason unknown.
Carl
Here is my dismal report. The signal rarely exceeded S3 but some of the rarely successful audio decoding occurred at S1 or even S0. Most of the time, the DX-394 was set max gain with AGC defeated. I find a little loss of gain whenever AGC is on and if the AGC voltage is changing, the 2nd Local Oscillator pulls a bit so I figure that could be a problem.
I'm amazed that Carl got a success rate 10 times higher! Would 200 kM (approx 16%) and 20-30 degrees difference in bearing make that much difference? I think not. The one encouraging thing is that there is still lots of room for improvement in my system - the challenge is: where?
Tom :confused:
Hi Tom,
I hope thatīs not too discouraging for you, but it seems I had a better signal today here in Europe at the back of the antenna, see attachment
73, Simone
Thanks, Simone - that's really encouraging! I'm suspicious that part of my problem is the anti-image filter or receiver alignment ahead of that. Most of the time the spectrum has a slope down towards the higher frequency. I just did a crude measurement without proper test equipment and the slope is as much as 12dB from 7kHz to 17kHz with ripple in between. I'm using a pair of Toko 6-element 455kHz ceramic filters in cascade. The image suppression is great and the overall bandwidth around 18-19kHz before the skirts take off. I might have better success if I could level off the passband. Not sure how to do that with cheap filters - no tweakers. I tried a 100pF capacitor in series between them and that seemed to have an effect - raised the upper side so that the passband response looks like a saddle with a valley in the centre.
Tom
chemclouds
25-07-2004, 00:01
Hello,
Not bad this evening. Only a few minor drop outs. 4 Hours long.
See Attachment.
Carl
chemclouds
25-07-2004, 02:04
Hello,
I missed the first half. My wife had a duty for me to perform.
No, it wasn`t that. Well, not this time anyway.
Reception on this freq. as usual was not very good. Here is the chart of the last half.
See attachment.
Carl
chemclouds
26-07-2004, 00:02
Hello,
I have only the last hour of todays transmission. Pretty good.
See Attachment.
Carl
chemclouds
26-07-2004, 02:06
Hello,
Still, not to good. Perhaps this is why.
Solar Activity Forecast: Solar activity is expected to be moderate to high. Region 652 has decayed somewhat, but still maintains good potential for a major flare.
Geophysical Activity Forecast: The geomagnetic field is expected to be at unsettled to severe storm levels. Minor to major storm periods are expected on day one as transient flow from the complex 23 July eruptions are expected to persist through much of 26 July. CMEs associated with today's M7 and long duration M1 flares will likely impact the geomagnetic field on 27 July and produce periods of major storming. Storm levels should subside by 28 July; a return to unsettled to active levels is expected by the end of the period. The greater than 10 MeV proton event in progress now, is expected to end on 26 July.
See Attachment.
Carl
No successful decoding here at all. Switched the converter to a DX-394B whose 2nd LO does not pull with changing IF gain but no breakthrough yet! There was an AM station at 6135 causing interference also. And the fading was awful - very rapid.
Tom
chemclouds
26-07-2004, 04:02
Hello,
Man, this s meter was jumping tonight, from 0 to 15 db.
The spectrum scope looked like it was doing the twist.
I logged only the last 20 minutes or so.
See Attachment.
Carl
chemclouds
27-07-2004, 00:14
Hello,
It was looking good for about 1.5 hrs. then there was a sudden drop. 4 Hours of data.
See Attachment.
Carl
chemclouds
27-07-2004, 02:03
Hello,
I maintained between 15 to 20 db of signal, with little fading.
However, the spectrum scope showed a very poor SNR from none to 8.3 max. I received no audio.
See Attachment.
Carl
chemclouds
27-07-2004, 04:16
Hello,
I have no log for tonight. I forgot to click the record button.
Maybe a explanation will suffice. Beginning at 0300 UTC signal strength was about 1 to 3 db. Software Radio would not lock to signal. SNR to low. After about 30 minutes signal strength increased to about 9 db. For the last 20 minutes software locked to signal, sync, data and audio. The highest SNR was 15 db. That`s it. I will try to be more observant in the future.
Carl
Well, at least on this one, Carl, we got the same results! Again, an AM station at 6135kHz here, almost understandable using LSB ECSS - better reception than with DRM!
Tom
chemclouds
27-07-2004, 17:15
Hi Tom,
I was looking at some of my past reports, and found a question that you asked me.
You asked what I have connected to this R75. I have inverted L. 11.8 meters in length 6 meters above ground,
with a 9:1 balun. Feeding this. COMMSCOPE 5731 RG6 50 OHM, WITH GROUND. Speaking of ground,
I don`t use a water pipe as a ground. I have found the resistance of these in some cases rather high, contributed to aging. where the pipes are joined together. I use a 3 meter solid copper rod. I do not use the shield of the
coax as the ground, although the shield does connect to the receiver. I use the ground wire that is attached to the jacket of the cable.
I think that maybe your problem is not with your receiver, but with your antenna. I am not saying that the antenna that you are using is
not of good design, I am sure it is. I have used similar ones. Antenna X may operate fine using receiver X at location A. Take antenna X and receiver X
to a differnet location, it could be a few km or a five hundred km. Your reception could drop in half,
or more. with terrible SNR. Here is a good example. Someone could take a 1 transistor regenerative receiver and conect it to a good antenna
and out perform a DRAKE R8 or a ICOM R75 or any receiver costing thousands of dollars if it is connected to a poor antenna.
Just a suggesstion.. Prehaps you have tried different antennas. It was good to hear that your reception is improving on 6140.
For your info. here is a image of the coax I am using.
See Attachment.
Carl
Hi Carl,
Actually, I was being funny. Your results last night fell to match mine - no audio decoded. Only thing wrong is that mine never get much better!
I don't think I have an antenna problem - that would affect reception in all modes. I'm sure it has something to do with oscillator phase noise (any or all of the three in the receiver and IF converter plus the computer A/D converter) and/or passband distortions, i.e., poor amplitude-frequency response or phase linearity, and/or non-linear gain giving rise to harmonic and intermod distortions. Lacking test gear, I'm blindly experimenting to find a breakthrough.
Keep up the good reporting. I'm sure the broadcasters are checking and appreciate it.
73, Tom
chemclouds
27-07-2004, 22:07
Hello,
We are having another thunder storm here.
Power outage prevented further logging.
Here is 3 hours of reception. Not to good.
If conditions permit, I will log 6140 tonight.
See Attachment.
Carl
chemclouds
28-07-2004, 00:55
Hello Tom,
I am confident that you will find the solution.
As a matter fact, I know you will.
Carl
chemclouds
28-07-2004, 02:05
Hello,
As usual not very good.
See Attachment.
Carl
chemclouds
29-07-2004, 00:04
Hello,
For the first 2 hrs. the reception was rather poor. But the last 2 hours improved tremendously. Here is 4 hours of data.
Carl
chemclouds
29-07-2004, 02:04
Hello,
This is one of the best reception reports I have logged on this frequency. For the first 15 minutes. I said here we go again, terrible as usual. But after the first 15 minutes it got pretty good. Keep up the good work.
Carl
I got about 1/5 or 1/6 your success, Carl - about 6-7% correctly decoded audio over the last 50 minutes. For the first 30, I was feeding my converter out of my DX-394A with its 2nd IF disconnected after the tap point so no AGC and no influence from its 2nd IF filters. Then switched to my DX-394B that is tapped at the same point without disconnecting the stock filter and buffered to the converter. Almost seemed like an instant improvement. The station at 6135 was relatively weaker tonight and propagation seemed to be more stable.
Tom
chemclouds
29-07-2004, 02:58
Hello Tom,
I am still confident that you will arrive at a conclusion soon.
You keep mentioning 6135. What is on 6135 ? Where is it originating ?
Any idea ? I haven`t noticed it here.
Here is a thought. I do not know the radiation pattern of CBC on 6140. Is it possible that when the Rf energy hits the ionosphere it is reflected back here with more energy then where you are ?
Seems rather interesting. There is a way to find out, if you are interested. Let me know.
Carl
chemclouds
29-07-2004, 04:21
Hey Tom,
If you are interested, I will start a new thread in GENERAL TOPICS. Called, Reception Experiment. It will take some work and time on my end, but that`s ok. Let me know if you are interested.
Carl
chemclouds
29-07-2004, 04:40
Hello CBC,
Last night at at 0300 UTC I tuned to this requency 11955.
Nothing was there. The s meter reading was 0 db. I switched in preamp 1. Still no signal. Ok, lets try preamp 2. Just atmospheric noise. That was the reason for no report.
Tonight, same time, same frequency, I received your signal that varied between 0 to 9 db with both preamps out of circuit, switched off! CHECK THIS OUT !!
Carl
chemclouds
30-07-2004, 00:08
Hello,
I was unable to be at the receiver for the first two hours of the transmission. Here is the chart for the last two.
Carl
.
Hi Carl,
According to ILGRadio database, the best bet is Radio Aparecida, Brazil, 25kW beaming 30 degrees followed by Radio Santa Cruz, Bolivia, 1kW beaming 0 deg. I can usually see a carrier spike on the DReaM spectrum just on the edge of the DRM signal.
As to the difference in reception between our two locations, yes, the azimuth and elevation angles from Sackville will be different. While the azimuthal differences might not be significant as far as the antenna pattern is concerned, the elevation angle could be. According to ILGRadio, they beam 268 degrees and I'm only 4 degrees off. The elevation angle for me is likely around 25 degrees and about 5 deg less for you. If the antenna's main vertical lobe is, say, 10 degrees, then my angle may be somewhat farther down the lobe than yours.
What do you have in mind for the topic Reception Experiments? I'm interested but time-challenged ;)
73, Tom
chemclouds
30-07-2004, 02:01
Gentlemen,
Give yourselves a pat on the back.
Carl
chemclouds
30-07-2004, 02:44
Hi Tom,
I will try to tune that in one one evening. Thanks.
I took a good part of the day today to try to find out why you are not getting CBC very well on 6140. This is what I did.
I built a small SW radio, very elementary. It consists of a very simple band pass filter with 6 db roll off at 3 and 8 MHZ. That is coupled into a mixer which is a 2N3904. The OSC. is also a 2N3904, tuned using a Varactor Diode. If out 455 KHZ. That is it. I tested it. You and I both know that a radio so simple will NOT out perform any DX-394. Now, this is what I have in mind. I will connect a Down Converter to it and use it to to receive the DRM signal on 6140. I will post the results. And I believe that I will have a better signal than you are gtting there. Why ? Because I think that the radiation pattern or the angle of it that CBC is using on 6140 when it hits the ionosphere, it is being reflected back here with greater energy than where you are. I do not buy the idea that your receiver has any serious problem. How about Monday night. I will log CBC using this elementary radio and post the results in the GENERAL TOPICS area. Thread name, Reception Experiment. There I will post the results.
How does that sound ? Want to go for it ?
Carl
chemclouds
30-07-2004, 04:01
Gentlemen,
Not bad this evening. It`s getting better.
Carl
chemclouds
30-07-2004, 15:44
Hello CBC,
I have a question. Can you make an adjustemnt to the Compandor or rather the compressor, to extend it`s Dynamic Range without causing stability broblems with the DRM Encoder Or rather the DRM Exciter ? It`s not too noticeable on voice. But on music, it is terrible. The quality is clean and crisp. It sounds as though the announcer is in my living room. If soneone there would post a reply, I would appreciate it.
Thank you,
Carl
Hi Carl,
Sounds like fun. Sure, I'll give it a go on Monday night. But I think it will not be conclusive. If you get poor results while the R75 does well and mine does poorly, you built a poor radio but the propagation differences are unknown. If you get good results while mine does poorly, then you built a good radio and the propagation differences remain unknown.
To conclude whether it is propagation or DX-394 that's at fault, I need a good radio here to compare it against. Maybe I should replicate your 2n3904 front end if you get better results with it than I do with the DX-394.
I'm willing to bet that the DX-394 could be a poor candidate for conversion, that it might have too much phase noise/jitter in the 1st or 2nd local oscillator. The first is a digital PLL freq synthesizer, the 2nd a varactor tuned 45MHz crystal oscillator. Here are some comments about the suitability of two other radios from Sat-Service Scheider:
"Grundig Yacht boy 400 At 2 of 3 tested receivers: Bad decoder S/N by peaks in phase noise of the LO. This gets to breaks in decoding, also by hardware blocking of the IF- counter- DAFC. Even though the IF- spectrum looks good. "
"NASA HF4E At some input signals DRM decoding is possible, but the performance is verry bad. Several reasons, changing of impedances at operating AGC, phase noise of LO, bad filter matching comression by gain controlling a.s.o. ."
Regards,
Tom
chemclouds
30-07-2004, 17:19
Hi Tom,
You said, "I think it will not be conclusive. If you get poor results while the R75 does well and mine does poorly, you built a poor radio but the propagation differences are unknown". I agree.
You are probably correct about this also. "I'm willing to bet that the DX-394 could be a poor candidate for conversion". I did not think about that ! I know very little about the DX-394.
Let me tell you, this radio is as simple as you can get for a superheterodyne. No RF stage no agc. I could go on and no. It brobably will turn out to be worthless for DRM. . I have not tested it for DRM. What the heck, Lets give it a shot on Monday evening.
I also have a Yaesu VR-500 that my wife gave me for christmas. It is still in the box. I have only had it on a few times. Neat Little radio. I contacted Yaesu, requesting a schematic a couple of days ago. I receive a reply stating that they will forward my request to the parts dept. The stock antenna that came with it is in my opinion is not very good. So, I replaced it.
I will soon see how the VR-500 performs at receiving DRM.
Thanks for the reply,
Carl
chemclouds
31-07-2004, 00:03
Hello CBC,
The first hour was rather rough. Here is 4 hours of data.
I asked a question earlier in this thread about compression. It is about 3 or 4 messages up.
Would you take the time and go back and read it and leave me a reply ?
Thank you,
Carl
chemclouds
31-07-2004, 02:02
Hello CBC,
I am waiting for a response to this question.
Can you make an adjustemnt to the Compandor or rather the compressor, to extend it`s Dynamic Range without causing stability broblems with the DRM Encoder Or rather the DRM Exciter ? It`s not too noticeable on voice. But on music, it is terrible. The quality is clean and crisp. It sounds as though the announcer is in my living room. If someone there would post a reply, I would appreciate it.
Thank you,
Carl
I missed the first 20 Minutes. Here is the last 40
chemclouds
31-07-2004, 04:00
Hello,
I was going to report, no log for this freq. tonight. It was that bad. However, you may be interested in a bad report. Ok, here is your bad report card.
Carl
chemclouds
31-07-2004, 19:18
Hello,
We all should work together !!!!
Waiting reply. No reply, no report.
Carl
chemclouds
01-08-2004, 01:29
Hello,
We all should work together !!!!
Waiting for reply. No reply, no further reports. FINAL REQUEST !!
Carl
chemclouds
01-08-2004, 13:42
Hello CBC,
I received an e-mail from Carsten, that inspired me to continue these reports. I will now release the reports. 1 of 2.
I know you guys are busy.
Carl
chemclouds
01-08-2004, 13:48
Gentlemen,
Here is the final one. 2 of 2. I did not log any for last night.
But, thanks to Carsten, I will continue.
Carl
Hi Carl and Tom,
Many thanks for the reports. It's nice to see that Carl is able to catch our program in good conditions and we hope that Tom will be able to enjoy DRM as well very soon. Is the receiver modified for DRM? Otherwise make sure to check the receiver modification pages on this www.drmrx.org website!
Ludo
chemclouds
02-08-2004, 00:01
Hello,
Very nice report card for this evening!
We are having a storm here and will try to get 6140 for you this evening.
Note: This is (4) hours worth of data.
Carl
chemclouds
02-08-2004, 02:05
Hello,
The storm prevented logging the first 8 minutes.
I had a few drop outs. The audio quality was very good .
HI LUDO,
I will be here Saturday to log another transmmission at 1600 UTC
Carl
Hey Carl, I got much better results tonight. Still not close to your R75 performance but much improved - 51% correctly decoded audio and max SNR of 20dB. Propagation must have improved but also I restored a post mixer amp that I had had in circuit a few weeks ago and took out because I was seeing harmonic distortion. I concluded that much of the HD and probably IMD was being generated in the NE612. With the addition of the amp, the shifted power spectral density looks much better close to 0 - probably a fair bit of hum or low freq buzz that is now suppressed.
Now getting 3995 ID'd as DW Wertachtel some of the time but can't quite get to audio....
Regards,
Tom
Max SNR Correctly Decoded Audio
----------- ------------------------------
Carl 22.8dB 61%
Tom ~18dB 37.6%
I wonder why the curves look so different - Carl's relatively smooth with little p-p variation compared to mine. Does DRM software outperform DReaM in maintaining sync and lockon speed? I know DReaM searches for the channel zero frequency over nearly the whole 24kHz channel while DRM requires it to be very close to 12kHz. Does DReaM spend a lot more time initiating the channel decoding? I have heard it takes about 4 seconds to acquire a station under ideal conditions.
Tom
chemclouds
02-08-2004, 04:23
Hello,
I understand this transmission is not beamed to the eastern US.
However, here is the report for tonight. NOT GOOD.
Hey Tom,
It`s good to hear your reception on 9800 has improved.
You also mentioned DREAM. I have used it but i like DRM Software Radio better. It takes longer for it to lock, i have a greater number of drop outs using it. It is a great software package. It reveals data about the DRM signal that the DRM software Radio does not.
All of my reports are made using DRM Software Radio-Merlin. It is so cool.
Are you still interested in doing the receiver experiment ?
This radio I built is not a professional design. I didn`t spend a lot of time on it. I haven`t connected a Down converter to it yet.
CBC here is the Attachment.
Carl
chemclouds
02-08-2004, 21:04
HELLO CBC,
NOAA WEATHER RADIO BROADCAST A STORM WATCH FOR CENTRAL VIRGINIA THIS EVENING. I WILL MAINTAIN LOG AS LONG AS POSSIBLE.
REGARDS,
CARL
chemclouds
03-08-2004, 00:03
Hello,
Here is 4 hours of data. Not to bad.
Hey Tom,
I have to cancel the receiver experiment for tonight due to weather conditions.
Carl
Here's my 4 hours. Comparing to Carl's:
--------Max SNR-------Correctly Decoded Audio---
Carl--- 26.3 dB ------- 87.1%
Tom -- 25 dB --------- 57.2%
I'm intrigued that I can sometimes get a fairly high SNR yet have so many dropouts. I suspect a high SNR is an indication that the receiver's phase noise, phase-frequency linearity, IMD, etc can't be very bad. I know the amplitude-frequency response is pretty good - I can see very flat-top rectangular spectrum often enough that it cannot be due to a fading pattern that is the exact complement of the filter ripple.
What I see is the DReaM readout of the channel's dc frequency is always changing and that when the software drops right back and re-scans it can come up 10-20 Hz away from what it last reported. I blew on my converter and that caused DReaM to re-scan. I think my 467kHz oscillator is unstable and, possibly, that is contributing to the frequent dropouts. Somehow, I got a 455kHz ceramic resonator to oscillate at 467kHz but maybe it's not really in control! I intend to replace it (or build a new converter) with a crystal and divider chain.
Carl, don't worry about the receiver test for my part. It might be fun to see how well it compares against your R75!
Tom
chemclouds
03-08-2004, 02:05
Hello,
The storm has passed. But we are getting a lot of rain.
Not to bad tonight considering the storm.
Carl
51.5% Correctly decoded audio
19-20dB Max SNR
Too bad a passing grade is 99.9%!
Tom
chemclouds
03-08-2004, 02:16
Hey Tom,
The receiver that I built compared to the R75 would be like comparing the speed of a bicycle to the speed of a Lamborghini. The weather conditions was not favourable for a test. Let`s try for tomorrow night.
Your reception on 6140 is looking better.
Carl
chemclouds
03-08-2004, 04:00
Hello,
On your report card for tonight, you get an A !!!
How about that. I don`t like sending out bad report cards.
Carl
chemclouds
04-08-2004, 00:02
Hello,
Here is your report. Not very good.
Carl
Tom,
I will be trying the receiver experiment on 6140 tonight.
CBC,
I will be unable to provide a reception report on 6140 this evening due to a receiver experiment.
Carl
chemclouds
04-08-2004, 02:23
Hello,
I did manage to log the last 30 minutes. Not good.
Carl
Tom,
Go to the Reception Experiment in the General Topics section.
I left a message for you.
Ragards,
Carl
chemclouds
04-08-2004, 03:57
HELLO CBC,
BEGINNING AFTER THIS REPORT I WILL REFRAIN FROM MAKING ANY FUTURE COMMENTS
UNLESS I FEEL IT`S IMPORTANT. I BELIEVE THE REPORTS SPEAK FOR THEMSELVES. I HAVE A LOT OF STUDYING TO DO. THANKS TO LUDO.
CARL
chemclouds
04-08-2004, 04:03
SORRY,
I FORGOT THE REPORT. HERE IT IS.
CARL
chemclouds
04-08-2004, 23:59
.
chemclouds
05-08-2004, 01:58
.
chemclouds
05-08-2004, 04:01
.
chemclouds
06-08-2004, 00:10
Hello,
We had a brief power outage here for a couple of minutes.
1 of 2 reports.
chemclouds
06-08-2004, 00:12
Hello,
We had a power Outage for about 3 minutes.
Log 1 of 2
chemclouds
06-08-2004, 00:15
Log 2 of 2
Carl
chemclouds
06-08-2004, 01:59
Hello,
I will be out of town tomorrow. I will try to be back by 1955 UTC if possible.
Carl
Carl,
Since you are using DRMSR, have you tried Carsten's automated logging tool. I can't remember if the R75 can be controlled by it but you could leave it tuned to the frequency while you are away and the software will start and stop DRMSR on schedule. If it can control the R75, then it can also change frequencies.
73, Tom
chemclouds
06-08-2004, 04:49
Hello,
I will be out of town tomorrow. I will try to be back by 1955 UTC if possible.
Hi Tom,
Carsten's automated logging tool does not support the R75 at this time. It is under development.
Thanks for suggesting it though.
Carl
chemclouds
07-08-2004, 00:33
Hello,
I returned home at 2345 UTC. I was out much longer than expected.
I will log 6140 and 11955 this evening.
Carl
chemclouds
07-08-2004, 02:13
Hey Ludo,
If you read this, I would like you to know that I did not realize that DRM has such tremendous capabilities.
I will be here Saturday at 1600 for TDPradio.
Later Ludo,
Carl
chemclouds
07-08-2004, 03:56
.
chemclouds
07-08-2004, 17:32
Hello,
TDPradio 1600 to 1700 UTC.
NASB 1700 to 1730 UTC.
Carl
chemclouds
07-08-2004, 23:58
1957 TO 2358 UTC.
chemclouds
08-08-2004, 02:02
0100 TO 0200 UTC.
Hello,
This is the best I Have logged on this Freq. You Get an A.
Carl
After many attempts and versions of oscillators and dividers, I finally got a one working with better stability than the 455kHz ceramic resonator pulled 12kHz off frequency! My first DRM reception with the new oscillator shows big improvement with some decent stretches with no dropouts. The converter went berserk a few times and propagation degraded too but I'm happy to see my logs looking more like Carl's.
Tom
chemclouds
08-08-2004, 04:00
0300 TO 0400 UTC.
What happened to my attachment ?
Carl
chemclouds
08-08-2004, 04:02
0300 TO 0400 UTC.
Hey Tom,
That is good news. Keep it up !
Want to have even better results ? Use DRM Software Radio Merlin.
Carl
Hi Carl,
Good so see that reception is strong and reliable in Richmond.
To Tom,
Now that seems you have solved your problems and are obtaining good results, it would be nice if you could try if TDPradio can be heard with good results in Toronto as well!
Ludo
Originally posted by chemclouds
Hello,
TDPradio 1600 to 1700 UTC.
NASB 1700 to 1730 UTC.
Carl
Hey Tom,
That is good news. Keep it up !
Want to have even better results ? Use DRM Software Radio Merlin.
Carl
I would if they gave it away, maybe even if they charged $9.95 to cover the licensing of certain elements. I do not understand why they would charge for it. It is a promotional, experimental, participatory research tool. The DRM developers, broadcasters, and manufacturers all benefit from getting a goodly number of radio and computer geeks (who else would bother?) enlisted in these activities in support of their longer term objectives. The number of people who would not buy a DRM receiver because they have decoding software on their computer should be a tiny fraction of the potential audience and sales, else there is no hope for DRM! 60 euros for the software is about the max that one would want to pay for an introductory radio....
Tom
This is looking better. Listening to DRM was enjoyable most of the time. Propagation from Sackville was probably excellent and Carl probably got 100% but I'm a lot happier with my converter and receiver. Now need to get the SNR up a bit for a bit more margin.
Tom
chemclouds
09-08-2004, 00:03
2005 TO 2359 UTC. You get an A
Hey Tom,
If conditions permit, you should listen to DTPradio on saturday at 1600 UTC.
It`s FAR OUT MUSIC.
chemclouds
09-08-2004, 02:00
0059 TO 0158 UTC.
Hey Tom,
If you are going to listen to TDPradio Saturday 1600 UTC. on 11900 KHZ.
Allow me to suggest this. GET STONED !!
chemclouds
09-08-2004, 04:03
Hello,
Last message until next weekend. Unless necessary. Studying to do.
Carl
chemclouds
09-08-2004, 23:59
19:56 TO 23:59 UTC
This was an experiment using the DX-394A front end, disconnected from its 2nd IF filter/amps so no AGC nor sharp filtering, feeding the downconverter with its anti-image filter bypassed. So the only filter is the 45MHz 1st IF ceramic filter. The shifted PSD looked very flat much of the time, only ripple due to selective fading. Observed SNR climb to over 25 dB initially although that's not reflected in the graph. Left it unattended most of the time so only tweaked the RF gain near the beginning. No idea whether signal strength went up or down towards the end where decoding and SNR fell off so don't know if degradation due to overload or reduced carrier SNR or whether some interference started.
Interesting - this follows testing with a lashed up DRM transmitter that showed a beautifully flat spectrum for 10kHz mode through to the decoder but only achieved 20 dB SNR. If the receiver can achieve 25 dB SNR off air, that indicates that the TX needs to be improved for it to be a very useful test and alignment tool.
Tom
chemclouds
10-08-2004, 02:01
01:01 to 01:59 UTC
Wow! Propagation was good tonight from Sackville but I have no log to show for it - forgot to close DRMcalc :mad:
Most amazing for this band - I saw the SNR creep over 26 dB at one point :) still using the DX-394A as a non-AGC tuner with selectivity determined only by the wide 45 MHz 1st IF filter. Image interference is much more of a problem on this band than 9800 kHz so I was surprised at how good the DRM SNR got. Sig strength was S9+20 at that point.
Carl, I see your logs showing 26dB Max SNR from time-to-time and I think I have seen one log in the reports section of the website showing 30dB. If I could get the DX-394 up to 25 or so with AGC and filtering, I'd be happier.
Tom
chemclouds
10-08-2004, 04:14
03:00 to 04:00 UTC.
chemclouds
10-08-2004, 23:57
19:55 to 23:59 UTC.
Still working off the DX-394A with no AGC nor any anti-image filter other than the 45 MHz barn door.
Strong similarities to Carl's last hour but my SNR and audio dropouts are much more variable.
Tom
chemclouds
11-08-2004, 02:01
00:59 TO 01:58 UTC.
chemclouds
11-08-2004, 03:58
03:02 to 03:59
chemclouds
12-08-2004, 00:00
23:12 to 23:59 UTC.
Hello,
Sorry for the delay. I was preoccupied.
Carl
chemclouds
12-08-2004, 02:10
01:00 to 01:59 UTC
chemclouds
12-08-2004, 03:59
03:27 to 0359
Hello,
No sync received until the time I started this log.
Carl
chemclouds
13-08-2004, 00:00
20:05 TO 01:00 UTC
chemclouds
13-08-2004, 02:00
01:02 TO 01:59 UTC
chemclouds
13-08-2004, 03:58
03:00 TO 03:59
chemclouds
14-08-2004, 00:14
Hello,
No report for 9800. Been monitoring Hurricane Watch Net. 14.325 MHZ.
Wind velocity 145 MPH. Also monitoring APT Weather Satellites.
Hurricane heading NNE at 9 MPH.
Here is a MSA Multispectral Analysis Image.
I will be logging 6140 this evening.
Carl
chemclouds
14-08-2004, 02:00
Hello,
Returning to 14.325 MHZ USB. Hurricane Watch Net. where the action is.
Will return at 03:00 UTC to log 11955.
Read this !!
Hurricane Charley, packing 145 mile (235 kilometer) an hour winds, hit the Florida coast amid fears that it could submerge large areas with a wall of water. The most powerful storm to hit Florida in more than a decade crossed the coast at Sanibel, just north of the major city of Fort Myers on the west coast.
Carl
chemclouds
14-08-2004, 04:04
Hello,
Reception not good tonight.
Tom, you haven`t checked in for for 2 or 3 days. Hope everything is ok.
Ludo, it looks as though Hurricane Charlie is headed this way.
At this moment we are having heavy rain and thunder storms
If conditions permit I will log TDPradio Saturday at 16:00 UTC.
Carl
Looks like I did better here "Down Under" today ;-) Still very poor though.
Cheers, Chris
chemclouds
14-08-2004, 04:34
Hi Chris,
You may think your reception on 11955 was very poor. But i think it was very good considering the distance. Lot better than my log for this freq. I would like to see further logs from you on 11955.
Best regards,
Carl
Hi Carl
Have a look for the thread I started called "BBC World Service 11955 kHz via Sackville". That's where I've normally been posting my logs of this transmission.
There are also some recordings from July on my DRM web page.
It's provided excellent reception here on some days - the best DRM signal (well, ok, pretty much the only!) here in NZ recently.
Unfortunately it's normally at 3pm local time here, and I'm at work. Reception always seems to be worse at weekends!
Cheers, Chris
chemclouds
14-08-2004, 05:00
Thanks Chris, I will check it out.
Cheers, i like that.
Cheers to you !!
Carl
chemclouds
14-08-2004, 17:05
TDPRadio 11900
Hi Ludo,
Thanks for the reply. Reception was very good today.
Heavy rain outside. NASB to follow.
Carl
chemclouds
14-08-2004, 17:29
NASB 17:07 TO 17:29 UTC
Hello,
Reception for NASB also very good.
Carl
chemclouds
14-08-2004, 21:35
Hello CBC,
Vinyl Cafe
The quality of your music is very good this afternoon. The low freq. the mids and the highs are very good. I am impressed !
We are still having heavy rain. Also expecting strong thunderstorms this evening. Will continue logging as long as possible,
Carl
chemclouds
15-08-2004, 00:02
Hello,
The hurricane is now a tropical storm. The rain has about diminished.
I enjoy the program Vinyl Cafe. I missed most of it today.
Will be here tonight for your transmisson on 6140.
Forgot the attachment.
chemclouds
15-08-2004, 00:04
Here is the log for 9800.
Carl
chemclouds
15-08-2004, 01:59
Hello,
No report, due to computer problem. Now corrected
Will log 11955.
Carl
Here's mine with dual 455 kHz filters in the converter that adversely affect the max SNR but help if there is image interference.
Tom
Converter with filters did not do so well. While signal very strong S9 up to +40, there seemed to be much spreading of the impulse response, sometimes two or three distinct pulses.
Tom
chemclouds
15-08-2004, 04:04
Hello Tom,
Welcome back !!
My reception on this freq. not good tonight.
Carl
chemclouds
16-08-2004, 00:04
19:55 to 00:04 UTC
Hello,
Here is my report for this freq. Not too bad.
Carl
chemclouds
16-08-2004, 01:58
01:00 TO 01:59
Hello,
As usual, not very good on this freq.
Carl
chemclouds
16-08-2004, 04:02
02:51 To 03:59
Hello,
Here is my desolate report for this freq. this evening.
Carl
chemclouds
17-08-2004, 00:00
20:00 TO 00:01 UTC
chemclouds
17-08-2004, 01:57
01:09 TO 01:59 UTC
Radio Budapest came up on freq a few minutes before 00:00 UT.
Tom
Aargh, it's so frustrating when you get overwhelming signal strength that would be great for AM but the multipath is so bad that the digits won't work.
Tom
chemclouds
17-08-2004, 03:57
3:02 TO 03:58
chemclouds
17-08-2004, 23:57
19:56 TO 23:58 GMT
chemclouds
18-08-2004, 01:56
01:05 TO 01:58 UTC
See the related posting on the meaning of multiple pulses in the DReaM "Estimated Channel Impulse Response" window and the curious behaviour of 6140 over the short distance from the transmitter (1231 km).
73, Tom
chemclouds
18-08-2004, 03:58
02:59 TO 03:58
chemclouds
18-08-2004, 23:57
20:51 TO 23:58
chemclouds
19-08-2004, 01:57
00:59 TO 02:00
chemclouds
19-08-2004, 03:56
02:59 TO 03:58
chemclouds
20-08-2004, 00:01
19:57 TO 00:01 UTC
chemclouds
20-08-2004, 02:06
01:00 TO 01:59
chemclouds
20-08-2004, 03:55
03:02 TO 03:59
chemclouds
21-08-2004, 00:01
19:58 TO 23:59
TDPRadio tomorrow. Far out !!!
My favorite, Vinyl Cafe.......
For the last hour the signal was excellent !!
Carl
chemclouds
21-08-2004, 02:00
01:01 TO 0159 UTC
chemclouds
21-08-2004, 03:58
03:02 TO 0358 utC
Hello,
Reception on this frequency was exceptionally good this evening.
One major problem. The Audio Data Stream was not modulated !!
Carl
chemclouds
21-08-2004, 16:56
It`s interesting, the last 3 reports have not been looked at.
Trying to tell me something ?
Ludo, here is TDPradio 16:00 to 16:59 UTC. If you are interested. NASB to Follow.
Carl
chemclouds
21-08-2004, 17:26
Hello,
The delay was due to DRMcalc running.
Well, I have the last 19 minutes.
Carl
chemclouds
22-08-2004, 00:01
CBC 20:01 TO 23:59
Hello,
Not too bad this evening. Had a rough start.
From about 21:30 to 23:59 reception was very good.
Looking forward to Vinyl Cafe tomorrow.
Carl
Caught the last 25 min. Not good.
chemclouds
22-08-2004, 01:57
01:00 TO 01:59
Hello,
Oh, I almost forgot. What happened to the audio last night on 11955 ? The Audio Data Stream was not modulated !
Did queer electrons blow a fuse ?
I happened again tonight on 6140 didn`t it ?
If it is abnormal electrons, better get rid of them !!
Carl
chemclouds
22-08-2004, 04:05
Hello,
No report. Signal level too low.
Carl
Hi DRMs,
after a long time a new experiment with Sackville on 9800 kHz.
Some audible moments with >mailbag< from RCI .....
regards, Michael
chemclouds
22-08-2004, 23:59
20:12 TO 23:59
chemclouds
23-08-2004, 01:59
01:00 TO 01:59
The signal was very good for the first 20 minutes and suddenly it went down hill.
Carl
chemclouds
23-08-2004, 03:02
Hello,
I will continue to monitor 11955 but I will not submit future logs for this frequency,
unless I receive a good signal. Unable to maintain lock.
No attachment, unusable signal.
Carl
chemclouds
24-08-2004, 01:56
Hello,
I was not here to stop the recording process in time.
Not bad though.
Carl
chemclouds
24-08-2004, 01:59
I was here for the beginning and ending of this one.
Carl
chemclouds
24-08-2004, 23:56
19:55 TO 23:59 UTC
chemclouds
25-08-2004, 01:58
01:08 to 01:59 UTC
See attached.
Carl - I'm getting bursts of audio from DW on 3995. Really strong signal - lousy impulse response.
Tom
No log, quick look, the spectrum, transfer response and estimated impulse response almost like what I see with my test generator - just the receiver characteristics. No selective fading, only very broad fades affecting all carriers. Often only one pulse ~1.5ms wide - beautiful propagation.
Tom
chemclouds
25-08-2004, 03:59
Hey Tom,
DW on 3995, that`s not bad!
I have never received audio on that freq. for DW. What ever you are doing, keep it up !
You are now getting better reception than I am.
Here is the log for CBC on 11955. just a few bits of audio.
Carl
chemclouds
25-08-2004, 23:57
I had to split for a while. Did not return in time for the beginning of transmission. Here is the last 2 hours.
Carl
Strong S9 to S9+40. Co-chan carrier 20-30dB above observed near end continued at S9 after shutdown. Was not monitoring until the last 5 minutes.
Tom
chemclouds
26-08-2004, 02:01
It did it again !!
Lots of dropouts due impulse spreading. Started late due monitoring RNWB Bonaire.
Tom
chemclouds
26-08-2004, 03:57
Much better reception this evening.
chemclouds
26-08-2004, 23:59
21:20 TO 23:59 UTC
Nice report card. A
Not bad.
Carl
chemclouds
27-08-2004, 02:06
01:00 TO 01:59 UTC
This is not good. F on your report card for this freq.
chemclouds
27-08-2004, 03:58
02:58 to 03:58
chemclouds
27-08-2004, 23:57
22:55 TO 23:59
I was unable to start log at beginning of broadcast. I was not here. Here is the last hour.
Carl
chemclouds
28-08-2004, 01:57
01:13 TO 01:59 UTC.
Signal level excellent. DRM radio showed low SNR. Also lots of dropouts.
Carl
Hi all,
some results of last night in Europe, see attachment
73, Simone
chemclouds
28-08-2004, 17:28
NASB 17:05 TO 17:29 UTC
Hi Simone,
Your reception on 9800 was very good for 5262 km.
Here is the report for NASB
Carl
chemclouds
29-08-2004, 00:13
20:09 TO 23:59 UTC
chemclouds
29-08-2004, 02:00
01:01 TO 0159 UTC
Hi Carl,
not so good last night during RCIīs hour with CBCīs Vinyl Cafe, but I always try to receive this great show, see attachment
73, Simone
chemclouds
29-08-2004, 16:50
Hello, Simone,
Yes I agree, Vinyl Cafe is a great show. I also had a few dropouts during this program.
Always good to hear from you Simone.
We have another Storm coming this way.
Go here. http://www.ssd.noaa.gov/PS/TROP/DATA/RT/float2-ir4-loop.html
Carl
chemclouds
29-08-2004, 23:57
Hello,
The log for my report on Saturday 04-08-28 for 9800 was accurate but the message field indicated 6140. That was not accurate. I am shure you detected it. However, the error is now corrected.
I was unable to start recording at 19:55 today. This report reflects the last 1.5 hours.
Carl
chemclouds
30-08-2004, 02:01
01:00 TO 01:59 UTC
Hello,
I am receiving excellent signal strength on this frequency but Software Radio shows low SNR.
I am going to see what I can do to improve it.
Carl
chemclouds
30-08-2004, 04:01
Hello,
Well, received a few bits of audio tonight.
Thought you may be interested.
Carl
chemclouds
30-08-2004, 22:21
19:52 TO 22:25 UTC.
The storm finally arrived. My back yard is under water. It looks like a river ! Rain is pouring here.
80 thousand customers in my area are without electrical power. Streets are closed, trees are down. Tornados have been spotted in various areas. Local Television Station are covering the damage as it occurs. My Broadband Internet connection went out earlier . We are having power fluctuation here. Here is the first 2.5 hours. If conditions permit, I will log 6140 this evening.
Carl
chemclouds
31-08-2004, 01:57
01:00 TO 01:58
Stormy and rainy weather continues.
chemclouds
01-09-2004, 00:01
20:10 TO 23:58
All of you that were logging the other frequencies better come back!! Seems like one guy is doing all of your jobs for you. Seems as though he is using 2 or 3 receivers to do the job. Where are you guys ? Still in the Twilight Zone ?
Here is the report for this freq.
Carl
chemclouds
01-09-2004, 01:55
01:23 TO 01:58
I had to split for a while. Returned at 01:22 UTC.
Here is a good part of it.
chemclouds
02-09-2004, 00:07
20:11 TO 23:58 UTC
Hello,
Reception would have been better if the transmitter hadn`t bit the dust. You guys got it back on air fast though.
Carl
Slooow access to the drmrx.org website last few days delayed this lousy report.
Tom
Now that's what I want to see! What a difference with 9800 kHz two hours earlier.
Tom
Started great, path faded out quickly.
Tom
Big improvement over last night. Observed estimated impulse response part of time - weak early pulse around 0 mS trailed by strong double pulse around 4 ms - equivalent to 1200 kM difference - coincidentally equal to the distance from Sackville to Toronto.
First use of DReaM 1.11csv - now supporting max SNR report in DRMcalc.
Tom
Another good night on 6140, at least the half-hour I observed. First and main subsequent pulse contending to be stronger and less than 2 ms apart with multiples close in to both.
Tom
chemclouds
02-09-2004, 01:58
Had a rough start for the first 15 minutes, and afterwards not too bad. You get a smiley face this evening.
Carl
chemclouds
03-09-2004, 00:04
23:19 TO 23:58 UTC.
The delay was due to monitoring Hurricane Watch Net. 14.325 MHZ USB. Yep, we have another one coming. Hurricane Frances.
Will be hitting the East Cost within a few hours. Packing winds around 238 Kilometers/Hour. Real time GOES Imagery is right here.
http://www.ssd.noaa.gov/PS/TROP/DATA/RT/float2-ir4-loop.html
For the length of time I logged this frequency, it wasn`t bad.
Going back to Huricane Watch Net. Here is a smiley face for you.
Carl :)
Covers a similar period to Carl's report but obviously conditions to Toronto changed. Initially the estimated impulse repsonse was superb - single major pulse at times as narrow as 1 ms. Wasn't at computer through much of the rest to comment on how that changed.
Tom
100% for last 38 minutes - guard band violation near beginning of transmission and close to it throughout.
Tom
chemclouds
03-09-2004, 02:02
01:08 TO 01:58 UTC
You barely made a passing grade. However, I will give you a smiley face in hopes you will do better.:)
Carl
chemclouds
03-09-2004, 21:25
Hello,
I will have no report for this evening or tonight on any frequency.
Antenna is down. I am in the process of constructing a large Magnetic Loop Antenna. If all goes well, I will be using it for future log report. Here is a smiley face for you. :)
Carl
Not good. Many guard interval violations.
Carl, I've been wanting to do a loop but I'm down in a ravine and think it needs to be up as high as my G5RV to be fair. I'll be interested in your observations.
Tom
Hi all,
not too bad last night in Germany, see attachment
73, Simone
chemclouds
04-09-2004, 13:04
Hey Ludo,
I forgot about TDPradio. Your broadcast is aired here only once a week. I have strung a tempoary antenna to log TDPradio today. Ludo, you have always been around to help me. I will not let you down. You will get your report, followed by NASB. :)
Carl
chemclouds
04-09-2004, 17:01
TDPradio
Hi Ludo.
I had a minor problem here. You will be getting 2 reports to complete your single report. This is report 1 of 2.
Carl
chemclouds
04-09-2004, 17:05
TDpradio
Ludo,
Here is report 2 of 2. These reports was logged on a temporary antenna. I am still in the process of constructing the Magnetic Loop.
Carl
Hi Carl,
Thanks for your report. It seems that in the first half hour, reception was not so good. Or was it because of the antenna?
Propagation is certainly strange today, because we could detect some signal (see attachment) and even a very little bit of audio around 1635 UTC, just before we switched on the recording.
Ludo
chemclouds
04-09-2004, 17:19
Hi Ludo,
I think it was due to both Propagation and the antenna. It is much shorter than the original one and it is orientated in a different direction. It is only temporary. My main antenna is down. I will have the Magnetic Loop installed this weekend.
Carl
chemclouds
04-09-2004, 17:26
NASB
Here is the last half of your broadcast.
No further log reports until Magnetic Loop is completed.
I will now remove temporary antenna.
NASB, here is your report for the last 15 minutes.
Carl
Hi Ludo,
I also tuned in, signal from Sackville was quite strong, but this frequency is already used here in Europe, but anyway some audio decoding was possible also later on the NASB broadcast, see attachment
73, Simone
Not good enough for relaxing listening. Too many interruptions with guard interval violations.
Tom
chemclouds
05-09-2004, 17:08
Hi,
The Magnetic Loop is up and running. At this time it is tuned to 9.800 MHZ.
It is rather large. It is 6 feet or rather 2 Meters in diameter. I am using Copper Tubing .5 inch or 1.27 Centimeters in diameter. I have some touchups to do on it. For example, painting, remote control the tuning and remote control the direction. At this point in time I am impresssed with it`s performance. We will see how well it operates for DRM at 19:55 UTC on 9.800 MHZ.
When I have the above mentioned items resolved, I will post more details along with an image in the Antennas section.
Carl
chemclouds
05-09-2004, 20:57
19:56 TO 20:59 UTC
Hello,
Since I am using a loop, I will be uploading hourly reports for comparison. Therefore I will be submitting 4 reports on this frequency, only for today. Future reports will be as usual 4 hours.
Log 1 of 4
Carl
chemclouds
05-09-2004, 21:55
23:19 TO 23:58 UTC
Hi,
There was a delay for about 7 minutes before beginning this log. The reason was the loop was not quite orientated in your direction. After turning it more precisely in your direction I noticed a sharp increase in gain. Here is report 2 of 4. Almost excellent 99.7%
Carl
Hi chemclouds,
nice to hear that the loop is already up and running.
How are the results compared to what you were using before (what was it exactly?)?
How large is the tuning capacitor? What kind of coupling?
With such a size you should not be far from its self-resonance frequency, so I guess, not much capacitance is needed for 9.8 MHz.
For DX reception (3995 kHz), you might also try to orientate the loop horizontally, this will generate much less signal but it will also attenuate noise and other signals arriving at higher incidence angles.
Roland
chemclouds
05-09-2004, 22:51
Hi Roland.
You mentioned, "nice to hear that the loop is already up and running."
Thank you. After all, you suggested it.
You asked " How are the results compared to what you were using before (what was it exactly?)?"
At this time Roland, the results seems to be superior.
The antenna I have been using was inverted L, 12 meters in length.
You asked, "How large is the tuning capacitor? What kind of coupling?"
The Tuning Cap. is from 20 to 350 pf. I may have to add more capacitance for 3995. I don`t know at this time. I haven`t tried tuning it to that freq. yet. The coupling is a small loop. 38 centimeters in diameter using 1.2 centimeters in diameter Copper Tubing.
You mentioned "With such a size you should not be far from its self-resonance frequency, so I guess, not much capacitance is needed for 9.8 MHz."
Very good Roland, I`m impressed. No, not much capacitance. I would say around 34 pf.
Thanks Roland,
Carl
chemclouds
05-09-2004, 22:57
22:03 TO 22:59
Hi,
It`s getting even better. 99.9%. This is the kind of report card I enjoy uploading. Log 3 of 4.
Carl
chemclouds
05-09-2004, 23:58
23:06 TO 23:59
Hi,
Man, You guys are doing good tonight. 99.9%.
Now, comes the challenge. 6140. That freq. has been giving me broblems for some time now. There is one problem I dislike about this loop. I have to climb a ladder to retune it. Remote control the thing I guess. Log 4 of 4.
Carl
Pretty good conditions over 4 hours. Some of the audio dropouts were due to my switching between my DX-394B with preamplified and filtered downconverter and my DX-394A with no AGC and a non-preamplified/non-filtered NE612 converter.
The higher SNR logged between 20:08 and 21:44 was on the latter. Some dropouts in there are possibly due to overload as I operated the gain as high as possible for max SNR or due to experiments with reduced gain and sudden increases of gain to see if the pulling of the 2nd Local Oscillator by gain setting was causing DReaM to lose synch - it was not evident even though it reported a shift of 10-12 Hz.
After 21:44, back onto the regular DX-394B. The lower SNR is possibly due to the filter shape or to the AGC causing the gain up to the 2nd IF to be lower than with the manually controlled DX-394A. Or it could be some non-linearity in the converter, or.....
The receiver was untouched from 21:44 to the end. The degradation in the last hour must have been propagation.
73, Tom
chemclouds
06-09-2004, 01:57
01:00 TO 01:58 UTC
Hi again,
The first few minutes did not look good. So, I went outside and turned the loop slightly. That did it. SNR increased dramatically. This is the best reception I have received on this frequency for a long time. I would go as far to say, if you want good DRM reception use a well designed loop. If you want proof, look at my past reports for this frequency without a loop. Roland ? Thanks man. As far as I am concern, you sent me a noise killer. Now going to 3995 if the antenna will tune that low with the cap. I have installd. Got to climb the ladder again.
Been a long time since you got a smiley face for this frequency.
Check out this report after turning the antenna slightly.
Carl
Pretty good after start. Missed the first 25 minutes - wonder if conditions were poorer then and improving as I tuned in. Some dropouts at beginning from adjusting my antenna tuner but also guard band violations. Strong signal throughout.
Carl, you had great results on 9800 with the loop. How did you do on 6140?
73, Tom
Originally posted by chemclouds
01:00 TO 01:58 UTC
Hi again,
The first few minutes did not look good. So, I went outside and turned the loop slightly. That did it. SNR increased dramatically. This is the best reception I have received on this frequency for a long time. I would go as far to say, if you want good DRM reception use a well designed loop. If you want proof, look at my past reports for this frequency without a loop. Roland ? Thanks man. As far as I am concern, you sent me a noise killer. Now going to 3995 if the antenna will tune that low with the cap. I have installd. Got to climb the ladder again.
Been a long time since you got a smiley face for this frequency.
Check out this report after turning the antenna slightly.
Carl
Well done, Carl! How much did you turn the loop for 6140 relative to your 9800 optimum? If you had not changed it in between, then I'm really surprised how touchy it is. Seems more like the way the null would behave. I wonder if there was a noise source that you were nulling out that gave the big rise in SNR.
I can just imagine you humping up and down the ladder to tune and steer. Next you'll have to get a rotator and a selsyn for the capacitor!
73, Tom
chemclouds
06-09-2004, 02:36
Hi tom.
Thanks for the reply. I understand the delay.
I thought I would try a loop instead of the sloper.
Tom, I turned it about 5 degrees to the East. Maybe it was propagation. I don`t know. Yes, I am going to remotely control the antenna. Up and down the ladder. Good exercise though.
Carl
chemclouds
07-09-2004, 00:00
21:15 TO 23:59 UTC
Hello,
I enjoy giving out report cards like this. Have another smiley face.
:)
Carl
chemclouds
07-09-2004, 02:02
01:00 TO 01:59 UTC
I don`t like giving bad report cards. I am holding Propagation conditions being at fault.
Tom, How was reception in Toronto ? Did you log this freq ? If so, upload it. I would like a comparison. It wasn`t very good here until the last few minutes.
Carl
Superb for the first 2-1/2 hrs then downhill; wasn't at computer to notice whether it was SNR or guard interval violations but graph suggests SNR was a major factor. Carl, yours was rock-solid all the way.
73, Tom
Originally posted by chemclouds
01:00 TO 01:59 UTC
Tom, How was reception in Toronto ? Did you log this freq ? If so, upload it. I would like a comparison. It wasn`t very good here until the last few minutes.
Carl
I only caught the last 20 minutes when your chart shows improvement. My 87% overall is pretty poor but it, too, improves for the last 7 minutes to 97%.
73, Tom
chemclouds
07-09-2004, 03:09
Thanks Tom,
Propagation conditions were not good until the last few minutes.
I am trying to get DW on 3995. I am still having problems with Ham Operators. I went outside and turned the antenna in hope to null them out. They seem to be everywhere.
Thanks again Tom.
Carl
Originally posted by chemclouds
I am still having problems with Ham Operators. I went outside and turned the antenna in hope to null them out. They seem to be everywhere.
Not an easy task to null them out, if they are all around you.
But why not try to mount the loop horizontally. It will then have an omnidirectional radiation pattern, but it will also favor the signals arriving at low incidence angles (ie DX signals) and attenuate signals at high incidence angles from more "nearby" stations. At least, that's what is written in the textbooks ...
'Roland
chemclouds
07-09-2004, 14:28
Thanks Roland,
Also, Propagation conditions will also play an important part, as we both know. Sounds good to me. I will place it in a horizontal plane, and see how it turns out. I will post the results here.
Carl
chemclouds
08-09-2004, 00:07
21:16 TO 23:58
Hi,
This is a rather strange looking log. Signal was very good, then suddenly it dropped straight down for a few moments then it shot straight up and stayed there. Not bad though. Loop is still in a vertical plane. Weather conditions has prevented attemps to reposition it. Been raining here today with mild thunder storms.
Expecting more rain tomorrow. However, I will position it in a horizontal plane when this rain ceases. I will post the results here.
Carl
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